/* ==========================================================================
   app.css — bố cục ứng dụng.
   Phân vùng bằng khoảng trắng, đường kẻ và nền loãng; bo góc chỉ giữ ở những
   thành phần thật sự cần một vùng chạm hoặc một lớp nổi.
   ========================================================================== */

/* ==========================================================================
/* ==========================================================================
   BỐ CỤC ỨNG DỤNG & THANH MENU CẠNH TRÁI (LEFT SIDEBAR)
   ========================================================================== */

.app-layout {
  display: block;
  min-height: 100vh;
  width: 100%;
}

/* Nút icon mở menu trên thanh Topbar */
.sidebar-toggle-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.35rem;
  height: 2.35rem;
  border-radius: var(--r-md);
  color: var(--ink);
  background: color-mix(in srgb, var(--ink) 5%, transparent);
  border: 1px solid var(--rule);
  cursor: pointer;
  transition: all var(--dur-fast) ease;
  flex-shrink: 0;
}

.sidebar-toggle-btn:hover {
  background: color-mix(in srgb, var(--accent) 12%, transparent);
  color: var(--accent);
  border-color: var(--accent);
}

.sidebar-toggle-btn .ico {
  width: 1.25rem;
  height: 1.25rem;
}

/* Logo Toppy cố định trên thanh Topbar */
.topbar-brand {
  display: inline-flex;
  align-items: center;
  gap: .55rem;
  text-decoration: none;
  color: inherit;
  flex-shrink: 0;
}

.topbar-brand .brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  border-radius: var(--r-md);
  background: color-mix(in srgb, var(--accent) 15%, transparent);
  color: var(--accent);
  box-shadow: 0 2px 8px color-mix(in srgb, var(--accent) 20%, transparent);
}

.topbar-brand .brand-text {
  display: flex;
  align-items: center;
  gap: .35rem;
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -.02em;
  color: var(--ink);
}

.topbar-brand .brand-badge {
  font-size: .65rem;
  font-weight: 700;
  padding: .15rem .45rem;
  border-radius: var(--r-sm);
  background: var(--accent);
  color: #fff;
  text-transform: uppercase;
  letter-spacing: .04em;
}

/* Lớp nền mờ khi mở Sidebar (Backdrop) */
.sidebar-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.35);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: 990;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

.sidebar-backdrop.is-open {
  opacity: 1;
  pointer-events: auto;
}

/* Thanh Sidebar dạng trượt từ cạnh trái */
.app-sidebar {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  width: 270px;
  max-width: 85vw;
  height: 100vh;
  display: flex;
  flex-direction: column;
  background: color-mix(in srgb, var(--bg-sunk) 92%, transparent);
  border-inline-end: 1px solid var(--glass-border);
  backdrop-filter: blur(28px) saturate(190%);
  -webkit-backdrop-filter: blur(28px) saturate(190%);
  padding: 1.15rem 0.85rem;
  box-shadow: 6px 0 28px rgba(0, 0, 0, 0.16);
  z-index: 1000;
  transform: translateX(-100%);
  transition: transform 0.28s cubic-bezier(0.16, 1, 0.3, 1);
  visibility: hidden;
}

.app-sidebar.is-open {
  transform: translateX(0);
  visibility: visible;
}

.sidebar-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: .25rem .5rem 1rem .5rem;
  border-block-end: 1px solid var(--rule);
  margin-block-end: .85rem;
}

.sidebar-head .sidebar-title {
  font-size: .95rem;
  font-weight: 700;
  color: var(--ink);
}

.sidebar-close-btn {
  color: var(--ink-muted);
}
.sidebar-close-btn:hover {
  color: var(--bad);
}

.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: .35rem;
  flex: 1;
  overflow-y: auto;
}

.sidebar-section {
  display: flex;
  flex-direction: column;
  gap: .25rem;
}

.sidebar-section-title {
  font-size: .68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--ink-faint);
  padding: .5rem .85rem .25rem;
}

.sidebar-divider {
  height: 1px;
  background: var(--rule);
  margin: .65rem .5rem;
}

.sidebar-nav-item {
  display: flex;
  align-items: center;
  gap: .85rem;
  padding: .65rem .85rem;
  border-radius: var(--r-md);
  text-decoration: none;
  color: var(--ink-muted);
  font-size: .92rem;
  font-weight: 500;
  background: transparent;
  border: none;
  cursor: pointer;
  transition: all var(--dur-fast) ease;
  text-align: left;
  width: 100%;
}

.sidebar-nav-item .ico {
  width: 1.25rem;
  height: 1.25rem;
  flex-shrink: 0;
  color: var(--ink-muted);
  transition: color var(--dur-fast), transform var(--dur-fast);
}

.sidebar-nav-item:hover {
  background: color-mix(in srgb, var(--accent) 8%, transparent);
  color: var(--ink);
  transform: translateX(3px);
}

.sidebar-nav-item:hover .ico {
  color: var(--accent);
}

.sidebar-nav-item.active {
  background: color-mix(in srgb, var(--accent) 15%, transparent);
  color: var(--accent);
  font-weight: 600;
}

.sidebar-nav-item.active .ico {
  color: var(--accent);
}

.sidebar-footer {
  margin-top: auto;
  padding-top: .75rem;
  border-block-start: 1px solid var(--rule);
}

.sidebar-footer-btn {
  color: var(--ink-muted);
}
.sidebar-footer-btn:hover {
  color: var(--ink);
}

/* Vùng nội dung chính và thanh Topbar */
.app-main-layout {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

.topbar {
  position: sticky;
  inset-block-start: 0;
  z-index: 40;
  padding-block: .65rem;
  background: color-mix(in srgb, var(--bg-sunk) 82%, transparent);
  border-block-end: 1px solid var(--glass-border);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  box-shadow: var(--shadow-soft-1);
}

.topbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.topbar-left {
  display: flex;
  align-items: center;
  gap: .85rem;
  flex: 1;
  min-inline-size: 0;
  max-width: 38rem;
}

.topbar-search {
  inline-size: 100%;
  max-width: 26rem;
  flex: 1;
}

.topbar-right {
  display: flex;
  align-items: center;
  gap: .45rem;
  flex-shrink: 0;
}

.app-content-body {
  flex: 1;
}

/* ==========================================================================
   New Mode — nhịp học, Pomodoro, công việc và ghi chú
   ======================================================================= */

.study-rhythm {
  padding-block: clamp(1rem, 3vw, 1.75rem);
  border-block: 1px solid var(--rule);
}

.study-streak {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  color: var(--ink-muted);
  font-size: var(--t-micro);
}

.study-streak .ico { color: var(--spark); }

.study-week-chart {
  display: block;
  inline-size: 100%;
  block-size: auto;
  max-block-size: 13rem;
  margin-block-start: .5rem;
  overflow: visible;
}

.study-week-chart rect {
  fill: color-mix(in srgb, var(--accent) 34%, transparent);
  rx: 2px;
}

.study-week-chart rect.is-peak { fill: var(--accent); }
.study-chart-value, .study-chart-label {
  fill: var(--ink-muted);
  text-anchor: middle;
  font-family: var(--font-num);
  font-size: 15px;
}
.study-chart-label { font-family: var(--font-body); font-size: 13px; }

.dashboard-task-notice {
  inline-size: 100%;
  display: flex;
  align-items: center;
  gap: .65rem;
  padding: .8rem 0;
  color: var(--ink);
  background: transparent;
  border: 0;
  border-block-end: 1px solid var(--rule);
  text-align: start;
}

.wrong-review-filters { display: grid; gap: .35rem; margin-block: 1rem; }
.wrong-due-switch { overflow-x: auto; flex-wrap: nowrap; padding-block-end: .2rem; }
.wrong-personal-note { margin-block-start: .9rem; padding-block-start: .8rem; border-block-start: 1px solid var(--rule); }
.wrong-note-text { white-space: pre-wrap; margin-block-end: .45rem; color: var(--ink); }
.wrong-note-input { min-block-size: 9rem; resize: vertical; }
.study-hub-tools { gap: .75rem; flex-wrap: wrap; }

.pomodoro-widget {
  position: fixed;
  z-index: 70;
  inset-inline-end: max(1rem, env(safe-area-inset-right));
  inset-block-end: max(1rem, env(safe-area-inset-bottom));
  inline-size: min(20rem, calc(100vw - 2rem));
  padding: 1rem;
  border: 1px solid var(--rule);
  background: color-mix(in srgb, var(--bg-sunk) 92%, transparent);
  box-shadow: var(--shadow-soft-3);
  backdrop-filter: blur(18px);
}

.pomodoro-time { font-size: clamp(2.4rem, 10vw, 4rem); line-height: 1; margin-block: .75rem; }
.pomodoro-preset { inline-size: 100%; margin-block-end: .75rem; }
.pomodoro-actions { flex-wrap: nowrap; }
.pomodoro-actions > * { flex: 1; justify-content: center; }

.tasks-page { padding-block: clamp(1.25rem, 4vw, 2.5rem) 5rem; }
.page-heading { align-items: start; gap: 1rem; }
.task-create { position: relative; }
.task-create > summary { list-style: none; cursor: pointer; }
.task-create > summary::-webkit-details-marker { display: none; }
.task-create[open] {
  inline-size: min(38rem, calc(100vw - 2rem));
  padding: 1rem;
  border: 1px solid var(--rule);
  background: var(--bg-sunk);
}
.task-create[open] > summary { margin-block-end: 1rem; }
.task-form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: .9rem; margin-block-end: 1rem; }
.task-field { display: grid; align-content: start; gap: .35rem; }
.task-field:nth-child(-n+2) { grid-column: 1 / -1; }
.task-status-row { display: flex; gap: .35rem; overflow-x: auto; padding-block: .3rem; }
.task-status-row > * { flex: none; }
.task-filters { display: grid; grid-template-columns: minmax(12rem, 1fr) minmax(10rem, .65fr) minmax(10rem, .65fr); gap: .65rem; }
.task-list { border-block-start: 1px solid var(--rule); }
.task-row { display: flex; align-items: start; gap: .8rem; padding-block: 1rem; border-block-end: 1px solid var(--rule); }
.task-row.is-done .task-copy { opacity: .62; }
.task-row.is-done .task-copy > strong { text-decoration: line-through; }
.task-check { inline-size: 1.35rem; block-size: 1.35rem; flex: none; border: 1px solid var(--ink-faint); background: transparent; color: var(--on-accent); padding: .12rem; }
.task-check.is-checked { border-color: var(--ok); background: var(--ok); }
.task-check .ico { inline-size: 100%; block-size: 100%; }
.task-copy { min-inline-size: 0; display: grid; gap: .3rem; }
.task-meta { margin-block-start: .2rem; }
.task-overdue { color: var(--bad); }
.task-actions { flex: none; justify-content: end; }

.notes-page { display: grid; grid-template-columns: minmax(16rem, .85fr) minmax(0, 2fr); min-block-size: calc(100dvh - 5rem); padding-block: 1.25rem 4rem; }
.notes-sidebar { padding-inline-end: 1rem; border-inline-end: 1px solid var(--rule); min-inline-size: 0; }
.notes-sidebar-head { align-items: start; margin-block-end: .8rem; }
.notes-subject-filter { inline-size: 100%; margin-block-end: .75rem; }
.notes-list { border-block-start: 1px solid var(--rule); }
.note-list-row { inline-size: 100%; display: grid; gap: .22rem; padding: .85rem 0; border: 0; border-block-end: 1px solid var(--rule); background: transparent; color: var(--ink); text-align: start; }
.note-list-row.is-active { color: var(--accent); }
.note-excerpt { overflow: hidden; white-space: nowrap; text-overflow: ellipsis; color: var(--ink-muted); font-size: var(--t-micro); }
.notes-editor { min-inline-size: 0; display: grid; grid-template-rows: auto auto auto minmax(22rem, 1fr); gap: .8rem; padding-inline-start: clamp(1rem, 3vw, 2rem); }
.notes-editor.is-empty { align-content: center; grid-template-rows: auto; }
.note-editor-head { min-block-size: 2.4rem; }
.note-title-input { inline-size: 100%; border: 0; border-block-end: 1px solid var(--rule); background: transparent; color: var(--ink); font: 700 var(--t-h1)/1.2 var(--font-display); padding: .45rem 0; }
.note-body-input { inline-size: 100%; min-block-size: 24rem; resize: vertical; border: 0; background: transparent; color: var(--ink); font: inherit; line-height: 1.7; padding: .5rem 0; }
.note-title-input:focus, .note-body-input:focus { outline: 0; border-color: var(--accent); }
.note-mobile-back { visibility: hidden; }

@media (max-width: 720px) {
  .pomodoro-widget {
    inset-inline: 1rem;
    inset-block-end: calc(5.8rem + env(safe-area-inset-bottom));
    inline-size: auto;
  }
  .task-form-grid, .task-filters { grid-template-columns: 1fr; }
  .task-field:nth-child(-n+2) { grid-column: auto; }
  .page-heading { display: grid; }
  .task-create, .task-create[open] { inline-size: 100%; }
  .task-row { flex-wrap: wrap; }
  .task-copy { inline-size: calc(100% - 2.5rem); }
  .task-actions { inline-size: 100%; padding-inline-start: 2.15rem; justify-content: start; }

  .notes-page { display: block; min-block-size: auto; }
  .notes-sidebar { border: 0; padding: 0; }
  .notes-editor { display: none; padding: 0; }
  .notes-page.is-editing-note .notes-sidebar { display: none; }
  .notes-page.is-editing-note .notes-editor { display: grid; }
  .note-mobile-back { visibility: visible; }
  .note-body-input { min-block-size: calc(100dvh - 17rem); }
}
.topbar .grow { flex: 1; }
.topbar h1 { font-size: 1.2rem; font-weight: 700; }
.brand-mark {
  display: grid;
  place-items: center;
  inline-size: 2.1rem;
  block-size: 2.1rem;
  border-radius: var(--r-md);
  background: linear-gradient(135deg, color-mix(in srgb, var(--accent) 22%, var(--bg-sunk)), color-mix(in srgb, var(--accent) 8%, var(--bg-sunk)));
  border: 1px solid color-mix(in srgb, var(--accent) 30%, var(--glass-border));
  color: var(--accent);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.04), inset 0 1px 0 rgba(255, 255, 255, 0.8);
  transition: transform var(--dur) var(--ease-out), box-shadow var(--dur);
}
.brand-mark:hover {
  transform: translateY(-1px) scale(1.04);
  box-shadow: 0 4px 12px color-mix(in srgb, var(--accent) 25%, transparent);
}
.brand-text {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--ink);
  display: flex;
  align-items: center;
  gap: 0.35rem;
}
.brand-badge {
  font-size: 0.65rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 0.15rem 0.4rem;
  border-radius: var(--r-pill);
  background: var(--accent-wash);
  color: var(--accent);
}

/* Nút */
.icon-btn {
  display: grid;
  place-items: center;
  inline-size: 2.4rem;
  block-size: 2.4rem;
  flex: none;
  border: 1px solid transparent;
  border-radius: var(--r-md);
  background: transparent;
  color: var(--ink-soft);
  cursor: pointer;
  transition: all var(--dur-fast);
}
.icon-btn:hover {
  background: var(--accent-wash);
  color: var(--ink);
  border-color: color-mix(in srgb, var(--accent) 20%, transparent);
  transform: translateY(-1px);
}
.ico-xl { inline-size: 2.5rem; block-size: 2.5rem; stroke-width: 1.5; color: var(--ink-faint); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  min-block-size: 2.4rem;
  padding: .5rem 1.05rem;
  border: 1px solid color-mix(in srgb, var(--accent) 60%, transparent);
  border-radius: var(--r-md);
  background: linear-gradient(180deg, color-mix(in srgb, var(--accent) 92%, #fff) 0%, var(--accent) 100%);
  color: var(--on-accent) !important;
  font-family: var(--font-display);
  font-size: var(--t-meta);
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08), inset 0 1px 0 rgba(255, 255, 255, 0.35);
  transition: all var(--dur-fast) var(--ease-out);
}
.btn:hover {
  background: linear-gradient(180deg, var(--accent) 0%, var(--accent-deep) 100%);
  box-shadow: 0 4px 14px color-mix(in srgb, var(--accent) 35%, transparent), inset 0 1px 0 rgba(255, 255, 255, 0.45);
  transform: translateY(-1px);
}
.btn:active { transform: translateY(1px); box-shadow: 0 1px 2px rgba(0, 0, 0, 0.12); }

/* Nút phụ — chỉ là chữ, không viền: giữ giao diện thoáng */
.btn-quiet {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding: .7em .25em;
  border: 0;
  background: none;
  color: var(--accent);
  font-family: var(--font-display);
  font-size: var(--t-meta);
  font-weight: 600;
  cursor: pointer;
}
.btn-quiet:hover { color: var(--accent-deep); }
.btn-danger { background: var(--bad); color: #fff !important; }
.btn-danger:hover { background: color-mix(in srgb, var(--bad) 82%, #000); }
.btn:disabled, .btn-quiet:disabled { opacity: .42; cursor: not-allowed; }
.btn-ghost {
  background: color-mix(in srgb, var(--bg-sunk) 88%, transparent);
  color: var(--accent) !important;
  box-shadow: inset 0 0 0 1px var(--accent);
}
.btn-ghost:hover { background: color-mix(in srgb, var(--bg-sunk) 72%, var(--accent-wash)); }

/* Tiến độ và danh sách */
.bar { block-size: 3px; overflow: hidden; background: var(--rule); }
.bar > i { display: block; block-size: 100%; transition: width var(--dur) var(--ease-out); }

.row {
  display: flex;
  align-items: center;
  gap: 1rem;
  inline-size: 100%;
  padding-block: 1rem;
  border: 0;
  background: none;
  color: inherit;
  font: inherit;
  text-align: start;
  cursor: pointer;
  transition: background var(--dur-fast);
}
.row:hover { background: color-mix(in srgb, var(--accent-wash) 55%, transparent); }
.row .grow { flex: 1; min-inline-size: 0; }
.row-static { cursor: default; }
.row-static:hover { background: none; }

/* Trạng thái rỗng và nạp file */
.empty { text-align: center; padding-block: clamp(3rem, 12vh, 6rem); }
.empty .meta { margin-inline: auto; }
.drop {
  display: grid;
  place-items: center;
  gap: .4rem;
  padding-block: clamp(2.5rem, 8vh, 4rem);
  border: 1px dashed var(--ink-faint);
  border-radius: var(--r-md);
  background: color-mix(in srgb, var(--bg-sunk) 84%, transparent);
  cursor: pointer;
  text-align: center;
  transition: border-color var(--dur-fast), background var(--dur-fast);
}
.drop:hover, .drop.over { border-color: var(--accent); background: var(--accent-wash); }
.drop input { display: none; }

/* Ô nhập và lớp nổi */
.field {
  inline-size: 100%;
  padding: .72rem .85rem;
  border: 1px solid var(--rule);
  border-radius: var(--r-sm);
  background: var(--bg-sunk);
  color: var(--ink);
  font: inherit;
  font-size: var(--t-body);
}
.field:focus-visible { outline: 2px solid var(--focus); outline-offset: 1px; }
.dlg {
  inline-size: min(100% - 2rem, 28rem);
  max-block-size: calc(100dvh - 2rem);
  overflow-y: auto;
  padding: 1.5rem;
  border: 1px solid var(--rule);
  border-radius: var(--r-lg);
  background: var(--bg-sunk);
  color: var(--ink);
  box-shadow: 0 18px 50px #0004;
}
.dlg::backdrop { background: #11182099; backdrop-filter: blur(2px); }
.dlg-actions { display: flex; justify-content: flex-end; align-items: center; gap: .75rem; flex-wrap: wrap; }
.toast {
  position: fixed;
  z-index: 60;
  inset-block-end: max(1.25rem, env(safe-area-inset-bottom));
  inset-inline: 0;
  display: flex;
  align-items: center;
  gap: .6rem;
  inline-size: max-content;
  max-inline-size: calc(100% - 2rem);
  margin-inline: auto;
  padding: .7rem 1rem;
  border-radius: var(--r-md);
  background: var(--ink);
  color: var(--bg);
  font-size: var(--t-meta);
  font-weight: 500;
  animation: rise var(--dur) var(--ease-out) both;
}
.toast-bad { background: var(--bad); color: #fff; }

/* Màn làm bài */
.clock { font-family: var(--font-num); font-variant-numeric: tabular-nums; font-weight: 700; font-size: 1.1rem; }
.clock.warn { color: var(--bad); animation: pulse 1s var(--ease-out) infinite; }
@keyframes pulse { 50% { opacity: .45; } }
.qgrid { display: flex; flex-wrap: wrap; gap: .35rem; }
.qgrid button {
  inline-size: 2.1rem;
  block-size: 2.1rem;
  border: 0;
  border-radius: var(--r-sm);
  background: var(--bg-sunk);
  color: var(--ink-faint);
  font-family: var(--font-num);
  font-size: .8rem;
  font-weight: 600;
  cursor: pointer;
}
.qgrid button:hover { background: var(--rule); }
.qgrid button[data-done="1"] { background: var(--accent-wash); color: var(--accent); }
.qgrid button[data-state="ok"] { background: var(--ok-wash); color: var(--ok); }
.qgrid button[data-state="bad"] { background: var(--bad-wash); color: var(--bad); }
.qgrid button[data-flag="1"] { box-shadow: inset 0 0 0 2px var(--spark); }
.qgrid button[aria-current="true"] { box-shadow: inset 0 -2px var(--accent); color: var(--ink); }
.qgrid button[aria-current="true"][data-flag="1"] {
  box-shadow: inset 0 -2px var(--accent), inset 0 0 0 1px var(--spark);
}
.footbar {
  position: sticky;
  z-index: 20;
  inset-block-end: 0;
  padding-block: .8rem;
  padding-block-end: max(.8rem, env(safe-area-inset-bottom));
  background: color-mix(in srgb, var(--bg) 94%, transparent);
  border-block-start: 1px solid var(--rule);
  backdrop-filter: blur(12px);
}
.footbar-inner { display: flex; align-items: center; gap: 1rem; }

/* Bố cục dùng chung */
.between { display: flex; align-items: center; justify-content: space-between; gap: 1rem; }
.cluster { display: flex; align-items: center; gap: .75rem; flex-wrap: wrap; }
.grow { flex: 1; min-inline-size: 0; }
.truncate { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.center { text-align: center; }
.hide { display: none !important; }

/* Điều hướng: Sliding Pill Navigation */
.nav-tabs-pill {
  position: relative;
  display: flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0.25rem;
  border-radius: var(--r-pill);
  background: color-mix(in srgb, var(--ink) 6%, transparent);
  border: 1px solid var(--glass-border);
}
.pill-indicator {
  position: absolute;
  top: 0;
  left: 0;
  border-radius: var(--r-pill);
  background: var(--bg-sunk);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08), inset 0 1px 0 rgba(255, 255, 255, 0.9);
  pointer-events: none;
  transition: transform 0.26s cubic-bezier(0.16, 1, 0.3, 1), width 0.26s cubic-bezier(0.16, 1, 0.3, 1), opacity 0.2s;
  z-index: 1;
}
[data-theme="dark"] .pill-indicator {
  background: color-mix(in srgb, var(--bg-sunk) 95%, var(--accent-wash));
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.12);
}
.nav-tab {
  position: relative;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  padding: .4rem .95rem;
  border: 0;
  border-radius: var(--r-pill);
  background: transparent;
  color: var(--ink-soft);
  font-family: var(--font-display);
  font-size: var(--t-meta);
  font-weight: 600;
  text-decoration: none;
  transition: color var(--dur-fast);
}
.nav-tab:hover { color: var(--ink); }
.nav-tab.active { color: var(--accent); }

/* Tìm kiếm & Command Search Bar */
.search-box {
  position: relative;
  display: flex;
  align-items: center;
  width: 100%;
}
.search-box > .ico {
  position: absolute;
  inset-inline-start: .85rem;
  color: var(--ink-faint);
  pointer-events: none;
}
.search-input {
  width: 100%;
  min-block-size: 2.45rem;
  padding: .5rem 2.8rem .5rem 2.45rem;
  border: 1px solid var(--rule);
  border-radius: var(--r-md);
  background: color-mix(in srgb, var(--bg-sunk) 85%, transparent);
  color: var(--ink);
  font: inherit;
  font-size: var(--t-meta);
  box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.04);
  transition: all var(--dur-fast);
}
.search-input:focus {
  outline: none;
  border-color: var(--accent);
  background: var(--bg-sunk);
  box-shadow: 0 0 0 3px var(--accent-wash), inset 0 1px 2px rgba(0, 0, 0, 0.02);
}
.search-cmd-badge {
  position: absolute;
  inset-inline-end: .55rem;
  display: inline-flex;
  align-items: center;
  gap: .15rem;
  padding: .15rem .45rem;
  border-radius: var(--r-sm);
  background: color-mix(in srgb, var(--ink) 6%, transparent);
  border: 1px solid var(--rule);
  color: var(--ink-faint);
  font-family: var(--font-num);
  font-size: 0.72rem;
  font-weight: 600;
  pointer-events: none;
}
.dashboard-search {
  inline-size: clamp(16rem, 28vw, 22rem);
  flex: none;
}
.search-dropdown {
  position: absolute;
  z-index: 50;
  inset-block-start: calc(100% + .45rem);
  inset-inline: auto 0;
  inline-size: min(28rem, calc(100vw - 2rem));
  max-height: 24rem;
  overflow-y: auto;
  border: 1px solid var(--glass-border);
  border-radius: var(--r-lg);
  background: var(--bg-glass);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  box-shadow: var(--shadow-soft-3);
  animation: rise var(--dur) var(--ease-out) both;
}
.search-item, .repo-item {
  display: flex;
  align-items: center;
  gap: .85rem;
  padding: .85rem 1rem;
  border-block-end: 1px solid var(--rule);
  cursor: pointer;
}
.search-item {
  inline-size: 100%;
  border-inline: 0;
  border-block-start: 0;
  background: transparent;
  color: var(--ink);
  font: inherit;
  font-size: var(--t-meta);
  text-align: start;
}
.search-item:last-child, .repo-item:last-child { border-block-end: 0; }
.search-item:hover, .repo-item:hover { background: var(--accent-wash); }
.search-result-count { flex: none; color: var(--ink-faint); font-size: var(--t-micro); }
.search-empty { padding: .85rem 1rem; color: var(--ink-soft); font-size: var(--t-meta); }

/* Các dải trạng thái */
.resume-banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  inline-size: 100%;
  padding: 1rem;
  border: 0;
  border-radius: 0;
  background: linear-gradient(90deg, var(--accent-wash), transparent 78%);
  color: var(--ink);
  font: inherit;
  text-align: start;
}
/* Dải nhắc việc gấp (bộ nhớ sắp đầy, lâu chưa sao lưu) — tông hổ phách */
.resume-banner.is-warn {
  background: linear-gradient(90deg, var(--spark-wash), transparent 78%);
}
.resume-banner.is-warn > .cluster > .ico { color: var(--spark); }

/* Chọn học kỳ và tab phụ: chữ + vạch, không pill */
.semester-nav, .sub-tabs {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  overflow-x: auto;
  border-block-end: 1px solid var(--rule);
  scrollbar-width: thin;
}
.semester-pill, .sub-tab-btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  flex: none;
  padding: .5rem 0 .7rem;
  border: 0;
  border-radius: 0;
  background: transparent;
  color: var(--ink-soft);
  font-family: var(--font-display);
  font-size: var(--t-meta);
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
}
.semester-pill:hover, .sub-tab-btn:hover { color: var(--ink); }
.semester-pill.active, .sub-tab-btn.active { color: var(--accent); }
.semester-pill.active::after, .sub-tab-btn.active::after {
  content: '';
  position: absolute;
  inset-inline: 0;
  inset-block-end: -1px;
  block-size: 2px;
  background: var(--accent);
}
.chip {
  display: inline-flex;
  align-items: center;
  gap: .25rem;
  padding: 0;
  border: 0 !important;
  border-radius: 0;
  background: transparent !important;
  color: var(--ink-faint);
  font-size: var(--t-micro);
  font-weight: 600;
}

/* Cây học tập */
.subject-card {
  padding-block: 1.2rem;
  border-block-start: 1px solid var(--rule);
}
.subject-card:first-child { border-block-start: 0; }
.repo-search { margin-block-end: 1rem; }
.repo-list { max-height: 20rem; overflow-y: auto; border-block: 1px solid var(--rule); }
.repo-item.selected { background: var(--accent-wash); }

/* Cài đặt hiển thị: đây là lựa chọn trực tiếp nên cho phép viền mảnh */
.palette-grid, .size-grid, .background-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: .5rem;
  margin-block-start: .75rem;
}
.palette-card, .size-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: .4rem;
  padding: .7rem .5rem;
  border: 1px solid var(--rule);
  border-radius: var(--r-sm);
  background: transparent;
  color: var(--ink);
  font: inherit;
  font-size: var(--t-meta);
  cursor: pointer;
}
.palette-card:hover, .size-card:hover { border-color: var(--ink-faint); }
.palette-card.active, .size-card.active { border-color: var(--accent); background: var(--accent-wash); }
.size-card { display: block; text-align: center; }
.palette-dot { inline-size: 1.3rem; block-size: 1.3rem; border-radius: 50%; }
.background-card {
  display: grid;
  gap: .4rem;
  overflow: hidden;
  padding: 0 0 .5rem;
  border: 1px solid var(--rule);
  border-radius: var(--r-sm);
  background: var(--bg-sunk);
  color: var(--ink-soft);
  font: inherit;
  font-size: var(--t-micro);
  font-weight: 600;
  cursor: pointer;
  text-align: center;
}
.background-card img {
  inline-size: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  filter: saturate(.82);
}
.background-card:hover { border-color: var(--ink-faint); color: var(--ink); }
.background-card.active {
  border-color: var(--accent);
  background: var(--accent-wash);
  color: var(--accent);
  box-shadow: inset 0 -2px var(--accent);
}

/* ==========================================================================
   NỀN ĐA TẦNG & KHÔNG GIAN THỊ GIÁC (RÕ NÉT PHONG CẢNH THIÊN NHIÊN)
   ========================================================================== */
.ambient-scenic-backdrop {
  position: fixed;
  z-index: 0;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

.ambient-scenic-img {
  position: absolute;
  inset: 0;
  inline-size: 100%;
  block-size: 100%;
  object-fit: cover;
  object-position: center 25%;
  opacity: 0.70;
  filter: saturate(1.15) contrast(1.05) blur(0px);
  transition: opacity 0.5s ease, filter 0.5s ease;
  will-change: transform;
}

[data-theme="dark"] .ambient-scenic-img {
  opacity: 0.65;
  filter: brightness(0.85) saturate(1.25) contrast(1.12) blur(0px);
}

.ambient-scenic-backdrop::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    color-mix(in srgb, var(--bg) 20%, transparent) 0%,
    color-mix(in srgb, var(--bg) 35%, transparent) 40%,
    color-mix(in srgb, var(--bg) 55%, transparent) 100%
  );
  pointer-events: none;
}

.ambient-radial-glow {
  position: absolute;
  top: 10%;
  left: 20%;
  width: 50vw;
  height: 50vw;
  max-width: 600px;
  max-height: 600px;
  border-radius: 50%;
  background: radial-gradient(circle, color-mix(in srgb, var(--accent) 15%, transparent) 0%, transparent 70%);
  filter: blur(40px);
  pointer-events: none;
  opacity: 0.3;
}

#app {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  background: transparent;
}

/* ==========================================================================
   DASHBOARD TỔNG QUAN — PREMIUM LEARNING DASHBOARD + SOFT 3D
   ========================================================================== */
.dashboard {
  padding-block: clamp(.25rem, .6vh, .5rem) 5rem;
  --dashboard-glass-line: rgba(9, 14, 18, .32);
  --dashboard-title: #090E12;
  --dashboard-copy: #10181D;
  --dashboard-faint: #1D282E;
  --dashboard-rule: rgba(9, 14, 18, .36);
  --dashboard-text-shadow: none;
}

:root[data-theme="dark"] .dashboard {
  --dashboard-glass-line: rgba(255, 255, 255, .2);
  --dashboard-title: #fff;
  --dashboard-copy: rgba(255, 255, 255, .88);
  --dashboard-faint: rgba(255, 255, 255, .72);
  --dashboard-rule: rgba(255, 255, 255, .2);
  --dashboard-text-shadow: 0 2px 14px rgba(0, 0, 0, .62);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .dashboard {
    --dashboard-glass-line: rgba(255, 255, 255, .2);
    --dashboard-title: #fff;
    --dashboard-copy: rgba(255, 255, 255, .88);
    --dashboard-faint: rgba(255, 255, 255, .72);
    --dashboard-rule: rgba(255, 255, 255, .2);
    --dashboard-text-shadow: 0 2px 14px rgba(0, 0, 0, .62);
  }
}

/* 1. Smart Greeting Hero & Real Photo Frame */
.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(18rem, 1fr);
  align-items: center;
  gap: clamp(1.5rem, 4vw, 3rem);
  padding-block: clamp(1rem, 3vh, 2.5rem) clamp(1.5rem, 4vh, 3rem);
}

.hero-copy {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.hero-date-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.3rem 0.75rem;
  border-radius: var(--r-pill);
  background: color-mix(in srgb, var(--bg-sunk) 90%, transparent);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-soft-1);
  color: var(--ink-soft);
  font-size: var(--t-micro);
  font-weight: 600;
  width: fit-content;
}

.dashboard-greeting {
  font-size: clamp(2rem, 1.75rem + 2.25vw, 3.35rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1.05;
  color: var(--ink);
  text-shadow: 0 1px 12px color-mix(in srgb, var(--bg) 40%, transparent);
}

.dashboard-prompt {
  color: var(--ink-soft);
  font-family: var(--font-display);
  font-size: clamp(1.08rem, 0.98rem + 0.5vw, 1.38rem);
  font-weight: 500;
  line-height: 1.45;
}

.hero-photo-frame {
  position: relative;
  border-radius: var(--r-card);
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-soft-3);
  transform-style: preserve-3d;
  background: var(--bg-sunk);
}

.hero-photo-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s var(--ease-out);
}

.hero-photo-frame:hover img {
  transform: scale(1.03);
}

.hero-photo-badge {
  position: absolute;
  bottom: 0.85rem;
  left: 0.85rem;
  right: 0.85rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.6rem 0.9rem;
  border-radius: var(--r-md);
  background: color-mix(in srgb, var(--bg-sunk) 85%, transparent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  color: var(--ink);
  font-size: var(--t-micro);
  font-weight: 600;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.08);
}

/* 2. 4 Study Metrics Cards */
.metrics-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
  margin-block-start: 1rem;
}

.metric-card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 1.25rem 1.35rem;
  border-radius: var(--r-card);
  background: color-mix(in srgb, var(--bg-sunk) 85%, transparent);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-soft-1);
  transform-style: preserve-3d;
  transition: transform var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease-out), border-color var(--dur);
}

.metric-card:hover {
  box-shadow: var(--shadow-soft-2);
  border-color: color-mix(in srgb, var(--accent) 30%, var(--glass-border));
}

.metric-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-block-end: 0.75rem;
}

.metric-icon-squircle {
  display: grid;
  place-items: center;
  inline-size: 2.3rem;
  block-size: 2.3rem;
  border-radius: var(--r-md);
  background: var(--accent-wash);
  color: var(--accent);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.6);
}

.metric-icon-squircle.spark { background: var(--spark-wash); color: var(--spark); }
.metric-icon-squircle.ok { background: var(--ok-wash); color: var(--ok); }
.metric-icon-squircle.bad { background: var(--bad-wash); color: var(--bad); }

.metric-indicator {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0.2rem 0.5rem;
  border-radius: var(--r-pill);
  font-size: 0.72rem;
  font-weight: 700;
  background: color-mix(in srgb, var(--ink) 5%, transparent);
  color: var(--ink-soft);
}
.metric-indicator.positive { background: var(--ok-wash); color: var(--ok); }
.metric-indicator.warning { background: var(--spark-wash); color: var(--spark); }

.metric-val {
  font-size: clamp(1.8rem, 1.4rem + 1.2vw, 2.4rem);
  font-weight: 800;
  line-height: 1.05;
  color: var(--ink);
  letter-spacing: -0.03em;
}

.metric-lbl {
  margin-block-start: 0.35rem;
  color: var(--ink-soft);
  font-size: var(--t-meta);
  font-weight: 500;
}

/* 3. Continue Learning Card (Buổi luyện đang làm dở - Main Feature) */
.continue-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 1.15rem;
  padding: 1.35rem 1.6rem;
  margin-block-start: 1.75rem;
  border-radius: var(--r-card);
  background: linear-gradient(135deg, color-mix(in srgb, var(--bg-sunk) 92%, var(--accent-wash)), color-mix(in srgb, var(--bg-sunk) 82%, transparent));
  border: 1px solid color-mix(in srgb, var(--accent) 35%, var(--glass-border));
  box-shadow: var(--shadow-soft-2);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  transform-style: preserve-3d;
  transition: transform var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease-out);
}

.continue-card:hover {
  box-shadow: var(--shadow-soft-3);
  border-color: var(--accent);
}

.continue-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.continue-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: var(--t-micro);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent);
}

.continue-body {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.continue-thumb {
  inline-size: 4.2rem;
  block-size: 4.2rem;
  border-radius: var(--r-md);
  object-fit: cover;
  flex: none;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.08);
  border: 1px solid var(--glass-border);
}

.continue-details {
  flex: 1;
  min-inline-size: 0;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.continue-title {
  font-family: var(--font-display);
  font-size: 1.18rem;
  font-weight: 700;
  color: var(--ink);
  text-overflow: ellipsis;
  overflow: hidden;
  white-space: nowrap;
}

.continue-progress-bar {
  block-size: 6px;
  border-radius: var(--r-pill);
  background: color-mix(in srgb, var(--ink) 8%, transparent);
  overflow: hidden;
}

.continue-progress-fill {
  block-size: 100%;
  border-radius: var(--r-pill);
  background: linear-gradient(90deg, var(--accent), color-mix(in srgb, var(--accent) 75%, #fff));
  transition: width 0.3s var(--ease-out);
}

.continue-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: var(--t-meta);
  color: var(--ink-soft);
}

.continue-actions {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  margin-inline-start: auto;
}

/* 4. Quick Actions Grid (4 Cards) */
.actions-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
  margin-block-start: 1.75rem;
}

.action-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  padding: 1.25rem 1.35rem;
  border-radius: var(--r-card);
  background: color-mix(in srgb, var(--bg-sunk) 85%, transparent);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-soft-1);
  color: var(--ink);
  text-align: start;
  cursor: pointer;
  transform-style: preserve-3d;
  transition: all 0.25s var(--ease-out);
}

.action-card:hover {
  background: color-mix(in srgb, var(--bg-sunk) 75%, var(--accent-wash));
  border-color: color-mix(in srgb, var(--accent) 40%, var(--glass-border));
  box-shadow: var(--shadow-soft-2);
  transform: translateY(-2px);
}

.action-card-icon {
  display: grid;
  place-items: center;
  inline-size: 2.6rem;
  block-size: 2.6rem;
  border-radius: var(--r-md);
  background: var(--accent-wash);
  color: var(--accent);
  transition: transform var(--dur) var(--ease-out);
}

.action-card:hover .action-card-icon {
  transform: scale(1.08) translateY(-1px);
}

.action-card.action-spark .action-card-icon { background: var(--spark-wash); color: var(--spark); }
.action-card.action-ok .action-card-icon { background: var(--ok-wash); color: var(--ok); }
.action-card.action-accent .action-card-icon { background: var(--accent-wash); color: var(--accent); }

.action-card-title {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.action-card-desc {
  font-size: 0.85rem;
  color: var(--ink-soft);
  line-height: 1.35;
}

/* 5. Section Insights (Daily Goal + Recent Subjects) */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-block-start: 2.5rem;
  margin-block-end: 1rem;
}

.section-title {
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.insights-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 1.8fr);
  gap: 1.25rem;
}

.insight-card {
  padding: 1.35rem 1.5rem;
  border-radius: var(--r-card);
  background: color-mix(in srgb, var(--bg-sunk) 85%, transparent);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-soft-1);
}

.recent-subjects-list {
  display: grid;
  gap: 0.65rem;
}

.recent-subject-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 1rem;
  border-radius: var(--r-md);
  background: color-mix(in srgb, var(--bg-sunk) 60%, transparent);
  border: 1px solid var(--rule);
  cursor: pointer;
  transition: all var(--dur-fast);
}

.recent-subject-row:hover {
  background: var(--accent-wash);
  border-color: var(--accent);
  transform: translateX(3px);
}

/* Dashboard tinh gọn: một tiêu điểm, các nhóm còn lại dùng nhịp và đường kẻ. */
.dashboard-hero {
  position: relative;
  background: transparent;
}

.dashboard-hero .hero-copy {
  position: relative;
  isolation: isolate;
  justify-self: start;
  inline-size: min(100%, 42rem);
}

.dashboard-hero-main {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(19rem, .85fr);
  gap: clamp(2rem, 5vw, 4.5rem);
  align-items: center;
  min-block-size: 20.5rem;
  padding: clamp(1.5rem, 3vw, 2.75rem) clamp(2rem, 5vw, 4rem);
}

.hero-date-line {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  width: fit-content;
  color: var(--dashboard-faint);
  font-size: var(--t-micro);
  font-weight: 600;
}

.dashboard-focus {
  position: relative;
  isolation: isolate;
  display: grid;
  gap: .85rem;
  padding: .25rem 0;
  background: transparent;
}

/* Kính chỉ là một lớp viền nằm sau nội dung: không nhuộm xám,
   không thay đổi nhịp chữ và vẫn nhìn xuyên rõ ảnh nền. */
.dashboard-hero .hero-copy::before,
.dashboard-focus::before {
  content: '';
  position: absolute;
  z-index: -1;
  inset: -1.05rem -1.15rem;
  border: 1px solid var(--dashboard-glass-line);
  border-radius: var(--r-lg);
  background: linear-gradient(135deg, rgba(255, 255, 255, .035), rgba(255, 255, 255, .008) 48%, transparent);
  box-shadow: inset 0 1px rgba(255, 255, 255, .13), 0 10px 30px -28px rgba(0, 0, 0, .75);
  backdrop-filter: blur(2px) saturate(112%);
  -webkit-backdrop-filter: blur(2px) saturate(112%);
  pointer-events: none;
}

.dashboard-suggestion-star {
  inline-size: .9rem;
  block-size: .9rem;
  color: var(--spark);
  fill: color-mix(in srgb, var(--spark) 18%, transparent);
  stroke-width: 1.8;
}

.dashboard-focus-top,
.dashboard-focus-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .8rem;
}

.dashboard-focus-title {
  font-family: var(--font-display);
  font-size: clamp(1.1rem, 1rem + .4vw, 1.35rem);
  font-weight: 700;
  line-height: 1.35;
  color: var(--dashboard-title);
}

.dashboard-focus-foot { margin-block-start: .15rem; }
.dashboard-focus-foot > .meta { max-inline-size: 20rem; }
.dashboard-focus-foot.is-action-only { justify-content: flex-end; }

.dashboard .dashboard-greeting,
.dashboard .dashboard-focus-title,
.dashboard .section-title,
.dashboard .dashboard-shortcut,
.dashboard .recent-subject-row {
  color: var(--dashboard-title);
  text-shadow: var(--dashboard-text-shadow);
}

.dashboard .dashboard-prompt,
.dashboard .meta {
  color: var(--dashboard-copy);
  text-shadow: var(--dashboard-text-shadow);
}

.dashboard .dashboard-prompt { white-space: nowrap; }

.dashboard .faint,
.dashboard .label {
  color: var(--dashboard-faint);
  text-shadow: var(--dashboard-text-shadow);
}

.dashboard-glance {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-auto-rows: 5.75rem;
  border-block-start: 1px solid var(--dashboard-rule);
}

.dashboard-glance-item {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: .55rem;
  min-inline-size: 0;
  min-block-size: 0;
  block-size: 100%;
  padding: .75rem clamp(.65rem, 2vw, 1.5rem);
  color: var(--dashboard-copy);
  font-size: var(--t-meta);
  font-weight: 500;
  text-align: center;
  text-shadow: var(--dashboard-text-shadow);
}

.dashboard-glance-item + .dashboard-glance-item {
  border-inline-start: 1px solid var(--dashboard-rule);
}

.dashboard-glance-item strong {
  color: var(--dashboard-title);
  font-size: 1.25rem;
  line-height: 1;
}

.dashboard-glance-item span { line-height: 1.35; }

.dashboard-glance-item.is-warn strong { color: var(--spark); }
.dashboard-glance-item.is-ok strong { color: var(--ok); }

.dashboard-shortcuts {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  margin-block-start: 0;
  border-block: 1px solid var(--dashboard-rule);
}

.dashboard-shortcut {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: .85rem;
  min-inline-size: 0;
  padding: 1rem 1.15rem;
  border: 0;
  background: transparent;
  color: var(--ink);
  font: inherit;
  text-align: start;
  cursor: pointer;
  transition: background var(--dur-fast), color var(--dur-fast);
}

.dashboard-shortcut + .dashboard-shortcut {
  border-inline-start: 1px solid var(--dashboard-rule);
}

.dashboard-shortcut:hover { background: var(--accent-wash); color: var(--accent); }

.dashboard-shortcut-icon {
  display: grid;
  place-items: center;
  inline-size: 2.25rem;
  block-size: 2.25rem;
  border-radius: 50%;
  background: var(--accent-wash);
  color: var(--accent);
}

.dashboard-shortcut-copy {
  display: grid;
  min-inline-size: 0;
  line-height: 1.35;
}

.dashboard-shortcut-copy strong { font-family: var(--font-display); font-size: var(--t-meta); }
.dashboard-shortcut-copy small { color: var(--dashboard-faint); font-size: var(--t-micro); font-weight: 500; }

.dashboard-recent {
  max-inline-size: 48rem;
  margin-block-start: clamp(1.75rem, 3vw, 2.5rem);
}

.dashboard-section-head { margin-block-end: .85rem; }
.dashboard-section-head .label { margin-block-end: .25rem; }

.dashboard-recent .recent-subjects-list { gap: 0; }
.dashboard-recent .recent-subject-row {
  inline-size: 100%;
  padding: .9rem .25rem;
  border: 0;
  border-block-start: 1px solid var(--dashboard-rule);
  border-radius: 0;
  background: transparent;
  color: var(--dashboard-title);
  font: inherit;
  text-align: start;
}

.dashboard-recent .recent-subject-row:last-child {
  border-block-end: 1px solid var(--dashboard-rule);
}

.dashboard-recent .recent-subject-row:hover {
  padding-inline: .75rem;
  border-color: var(--rule);
  background: linear-gradient(90deg, var(--accent-wash), transparent 80%);
  color: var(--accent);
  transform: none;
}

@media (max-width: 56rem) {
  .dashboard-hero-main { grid-template-columns: 1fr; min-block-size: auto; }
  .dashboard .dashboard-prompt { white-space: normal; }
  .dashboard-shortcuts { grid-template-columns: 1fr; }
  .dashboard-shortcut + .dashboard-shortcut {
    border-inline-start: 0;
    border-block-start: 1px solid var(--dashboard-rule);
  }
}

@media (max-width: 36rem) {
  .dashboard { padding-block-start: .25rem; }
  .dashboard-hero-main { padding: 1.5rem; gap: 1.5rem; }
  .dashboard-greeting { font-size: clamp(2rem, 12vw, 3rem); }
  .dashboard-focus-foot { align-items: flex-end; flex-wrap: wrap; }
  .dashboard-focus-foot .btn { inline-size: 100%; }
  .dashboard-hero .hero-copy::before,
  .dashboard-focus::before { inset: -.75rem; }
  .dashboard-glance-item { display: grid; justify-items: center; gap: .1rem; text-align: center; }
  .dashboard-glance-item span { font-size: .68rem; line-height: 1.3; }
}

/* 6. Command Palette Search Modal */
.cmd-modal-backdrop {
  position: fixed;
  inset: 0;
  z-index: 100;
  background: rgba(15, 23, 30, 0.6);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  display: grid;
  place-items: start center;
  padding-block-start: 12vh;
  padding-inline: 1rem;
  animation: fadeIn 0.18s ease-out both;
}

@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.cmd-modal-card {
  inline-size: min(100%, 36rem);
  border-radius: var(--r-card);
  background: var(--bg-sunk);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-soft-3), 0 25px 50px -12px rgba(0,0,0,0.25);
  overflow: hidden;
  animation: dlgPop 0.22s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.cmd-search-input-wrap {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  border-block-end: 1px solid var(--rule);
}

.cmd-search-input {
  width: 100%;
  border: 0;
  background: transparent;
  color: var(--ink);
  font: inherit;
  font-size: 1.1rem;
  outline: none;
}

.cmd-results-list {
  max-height: 22rem;
  overflow-y: auto;
  padding: 0.5rem;
}

.cmd-item {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  padding: 0.75rem 0.95rem;
  border-radius: var(--r-md);
  color: var(--ink);
  cursor: pointer;
  transition: background var(--dur-fast);
}

.cmd-item:hover, .cmd-item.selected {
  background: var(--accent-wash);
  color: var(--accent);
}

.cmd-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.65rem 1.25rem;
  border-block-start: 1px solid var(--rule);
  background: color-mix(in srgb, var(--bg-sunk) 95%, transparent);
  font-size: 0.78rem;
  color: var(--ink-faint);
}

/* ==========================================================================
   STUDY WORKSPACE (PHẦN 2/3)
   Bố cục làm bài tập trung, Question Card, Answer Options, Explanation Panel,
   Focus Mode, Session Panel & Question Navigator Grid
   ========================================================================== */

/* Khung tổng thể Study Workspace (3 cột desktop / 1 cột mobile) */
.study-workspace-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 17rem;
  gap: clamp(1.25rem, 3vw, 2.25rem);
  align-items: start;
  padding-block: clamp(1.25rem, 3vw, 2rem) 4rem;
  transition: all var(--dur) var(--ease-out);
}

.study-main-col {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

/* Header thanh công cụ làm bài */
.study-header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  background: var(--bg-sunk);
  border: 1px solid var(--rule);
  border-radius: var(--r-md);
  margin-block-end: 0.5rem;
}

.study-header-left {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-width: 0;
}

.study-header-title {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--ink);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.study-header-actions {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.tool-btn {
  font-family: inherit;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  min-block-size: 2.25rem;
  padding: 0.4rem 0.75rem;
  border: 0;
  border-radius: var(--r-pill);
  background: transparent;
  color: var(--ink-soft);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--dur-fast);
}

.tool-btn:hover {
  background: var(--accent-wash);
  color: var(--ink);
}

.tool-btn.active {
  background: var(--accent-wash);
  color: var(--accent);
}

/* Bề mặt đọc câu hỏi: một mảng nền mềm, không viền hộp cứng */
.question-card {
  background:
    linear-gradient(145deg,
      color-mix(in srgb, var(--bg-sunk) 96%, var(--accent-wash)),
      color-mix(in srgb, var(--bg-sunk) 88%, transparent));
  border: 0;
  border-radius: var(--r-card);
  padding: clamp(1.25rem, 3.5vw, 2.25rem);
  box-shadow: var(--shadow-soft-1);
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  position: relative;
  overflow: hidden;
}

.question-card::before {
  content: '';
  position: absolute;
  inset: 0 0 auto;
  block-size: 3px;
  background: linear-gradient(90deg, var(--accent), color-mix(in srgb, var(--accent) 12%, transparent) 72%, transparent);
  opacity: .75;
}

.question-meta-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--ink-faint);
}

.question-context {
  display: flex;
  align-items: center;
  gap: .65rem;
  min-inline-size: 0;
}

.question-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.25rem 0.6rem;
  background: var(--accent-wash);
  border: 0;
  border-radius: var(--r-pill);
  font-weight: 600;
  color: var(--accent);
  font-family: var(--font-num);
}

.question-text-content {
  font-family: var(--font-body);
  max-inline-size: 58rem;
  font-size: var(--t-q);
  line-height: 1.55;
  color: var(--ink);
  font-weight: 500;
}

/* Danh sách Thẻ Lựa chọn Đáp án (Answer Options) */
.answer-options-list {
  display: grid;
  gap: 0;
  margin-block-start: 0.35rem;
}

.answer-option-card {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 1rem;
  min-block-size: 3.65rem;
  padding: 0.9rem 1rem;
  border: 0;
  border-radius: var(--r-md);
  background: transparent;
  color: var(--ink);
  text-align: start;
  cursor: pointer;
  box-shadow: none;
  transition: transform var(--dur-fast) var(--ease-out), background var(--dur-fast), box-shadow var(--dur-fast);
  position: relative;
  user-select: none;
}

.answer-option-card + .answer-option-card {
  border-block-start: 1px solid color-mix(in srgb, var(--rule) 72%, transparent);
}

.answer-option-card:hover:not(:disabled) {
  background: color-mix(in srgb, var(--bg-sunk) 72%, var(--accent-wash));
  box-shadow: none;
  transform: translateY(-1px);
}

.answer-option-key {
  display: grid;
  place-items: center;
  width: 1.85rem;
  height: 1.85rem;
  border: 0;
  border-radius: 50%;
  background: color-mix(in srgb, var(--ink) 7%, transparent);
  font-family: var(--font-num);
  font-weight: 700;
  font-size: 0.85rem;
  color: var(--ink-soft);
  transition: all var(--dur-fast);
}

.answer-option-text {
  font-size: 1rem;
  line-height: 1.45;
  color: inherit;
}

.answer-option-status-icon {
  display: grid;
  place-items: center;
  width: 1.4rem;
  height: 1.4rem;
  opacity: 0;
  transition: opacity var(--dur-fast);
}

/* 6 Trạng thái Đáp án */
/* State: Selected */
.answer-option-card.is-selected {
  background: var(--accent-wash);
  color: var(--ink);
  box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--accent) 28%, transparent);
}
.answer-option-card.is-selected .answer-option-key {
  background: var(--accent);
  color: var(--on-accent);
}

/* State: Correct (Chính xác) */
.answer-option-card[data-state="ok"] {
  background: var(--ok-wash) !important;
  color: var(--ink) !important;
  box-shadow: none !important;
}
.answer-option-card[data-state="ok"] .answer-option-key {
  background: var(--ok);
  color: var(--on-ok);
}
.answer-option-card[data-state="ok"] .answer-option-status-icon {
  opacity: 1;
  color: var(--ok);
}

/* State: Wrong (Sai) */
.answer-option-card[data-state="bad"] {
  background: var(--bad-wash) !important;
  color: var(--ink) !important;
  box-shadow: none !important;
}
.answer-option-card[data-state="bad"] .answer-option-key {
  background: var(--bad);
  color: var(--on-bad);
}
.answer-option-card[data-state="bad"] .answer-option-status-icon {
  opacity: 1;
  color: var(--bad);
}

/* State: Disabled */
.answer-option-card:disabled {
  cursor: default;
}

/* Khung Giải thích (Explanation Panel) */
.explanation-panel {
  margin-block-start: .65rem;
  border-radius: var(--r-md);
  border: 0;
  background: linear-gradient(90deg, var(--accent-wash), transparent 86%);
  padding: 1rem 1.15rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  animation: expSlide 0.22s var(--ease-out) both;
}

@keyframes expSlide {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

.explanation-panel.is-correct {
  background: linear-gradient(90deg, var(--ok-wash), transparent 86%);
}

.explanation-panel.is-wrong {
  background: linear-gradient(90deg, var(--bad-wash), transparent 86%);
}

.exp-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
}

.exp-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-weight: 700;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.exp-badge.is-correct { color: var(--ok); }
.exp-badge.is-wrong { color: var(--bad); }

.exp-body {
  font-size: 0.95rem;
  line-height: 1.55;
  color: var(--ink);
}

.exp-tip-box {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  padding: 0.65rem 0.85rem;
  border-radius: var(--r-sm);
  background: var(--bg);
  border: 1px solid var(--rule);
  font-size: 0.85rem;
  color: var(--ink-soft);
}

/* Thanh Điều hướng & Phím tắt (Study Action Bar) */
.study-nav-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-block-start: .25rem;
}

.study-nav-bar .btn-ghost,
.exam-nav-actions .btn-ghost {
  background: transparent;
  box-shadow: none;
  color: var(--ink-soft) !important;
}

.study-nav-bar .btn-ghost:hover,
.exam-nav-actions .btn-ghost:hover {
  background: var(--accent-wash);
  color: var(--accent) !important;
}

.study-nav-shortcuts {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.78rem;
  color: var(--ink-faint);
}

.study-nav-shortcuts kbd {
  padding: 0.15rem 0.35rem;
  border: 1px solid var(--rule);
  border-radius: 4px;
  background: var(--bg-sunk);
  font-family: var(--font-num);
}

/* Khung Thống kê Phiên học (Session Panel) */
.session-panel {
  background: color-mix(in srgb, var(--bg-glass) 94%, transparent);
  border: 0;
  border-radius: var(--r-card);
  padding: 1.15rem;
  box-shadow: none;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  position: sticky;
  top: 4.5rem;
}

.session-summary {
  display: grid;
  gap: .9rem;
  padding-block: .85rem;
  border-block: 1px solid color-mix(in srgb, var(--rule) 72%, transparent);
}

.session-primary-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: .75rem;
}

.session-primary-stat {
  display: grid;
  gap: .12rem;
}

.session-primary-stat.align-end { text-align: end; }

.session-mini-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: .45rem;
}

.session-mini-stats > div {
  display: grid;
  gap: .08rem;
}

.session-mini-stats > div + div {
  padding-inline-start: .55rem;
  border-inline-start: 1px solid var(--rule);
}

.session-mini-stats .session-stat-val { font-size: .95rem; }

.session-panel-title {
  font-weight: 700;
  font-size: 1rem;
  color: var(--ink);
}

.session-stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.65rem;
}

.session-stat-box {
  padding: 0.75rem;
  background: var(--bg);
  border: 1px solid var(--rule);
  border-radius: var(--r-sm);
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.session-stat-box.full-w {
  grid-column: span 2;
}

.session-stat-lbl {
  font-size: 0.75rem;
  color: var(--ink-faint);
  font-weight: 500;
}

.session-stat-val {
  font-family: var(--font-num);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--ink);
}

.session-stat-val.ok { color: var(--ok); }
.session-stat-val.bad { color: var(--bad); }

/* Bảng Điều hướng Câu hỏi (Question Navigator Grid) */
.nav-grid-box {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.nav-grid-filters {
  display: flex;
  gap: 0.35rem;
  overflow-x: auto;
  padding-bottom: 0.25rem;
}

.nav-filter-btn {
  padding: 0.25rem 0.55rem;
  border: 0;
  border-radius: var(--r-pill);
  background: color-mix(in srgb, var(--ink) 5%, transparent);
  color: var(--ink-faint);
  font-size: 0.75rem;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
}

.nav-filter-btn.active {
  background: var(--accent);
  color: var(--on-accent);
  border-color: var(--accent);
}

.nav-questions-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0.4rem;
  max-height: 14rem;
  overflow-y: auto;
  padding: 2px;
}

.nav-q-btn {
  position: relative;
  aspect-ratio: 1;
  border: 1px solid var(--rule);
  border-radius: 9px;
  background: var(--bg);
  color: var(--ink-soft);
  font-family: var(--font-num);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: all var(--dur-fast);
}

.nav-q-btn:hover {
  background: var(--rule);
}

.nav-q-btn.current {
  border-color: var(--accent);
  box-shadow: inset 0 0 0 1px var(--accent);
  font-weight: 700;
}

.nav-q-btn.is-done {
  background: var(--accent-wash);
  color: var(--accent);
}

.nav-q-btn.is-ok {
  background: var(--ok-wash);
  border-color: var(--ok);
  color: var(--ok);
}

.nav-q-btn.is-bad {
  background: var(--bad-wash);
  border-color: var(--bad);
  color: var(--bad);
}

.nav-q-btn.is-flagged::after {
  content: '';
  position: absolute;
  top: 2px;
  right: 2px;
  width: 5px;
  height: 5px;
  background: var(--spark);
  border-radius: 50%;
}

/* Chế độ Focus Mode */
body.is-focus-mode .topbar,
body.is-focus-mode .session-panel,
body.is-focus-mode .study-sidebar {
  display: none !important;
}

body.is-focus-mode .study-workspace-layout {
  grid-template-columns: 1fr;
  max-width: 50rem;
  margin-inline: auto;
}

/* Exam Mode (Thi thử) */
.exam-config-wrap {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(19rem, 25rem);
  gap: clamp(2rem, 7vw, 6rem);
  align-items: center;
  min-block-size: calc(100dvh - 4.5rem);
  padding-block: clamp(2.5rem, 8vh, 6rem);
}

.exam-config-intro {
  display: grid;
  align-content: start;
  gap: .8rem;
  max-inline-size: 38rem;
}

.exam-config-icon {
  display: grid;
  place-items: center;
  inline-size: 4.25rem;
  block-size: 4.25rem;
  margin-block-end: .75rem;
  border-radius: 50%;
  background: var(--accent-wash);
  color: var(--accent);
}

.exam-config-icon .ico-xl { color: currentColor; }

.exam-config-panel {
  overflow: hidden;
  border-radius: var(--r-card);
  background: color-mix(in srgb, var(--bg-glass) 94%, transparent);
  box-shadow: var(--shadow-soft-1);
}

.exam-config-field {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.25rem;
}

.exam-config-label {
  display: block;
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--ink);
}

.exam-duration-control {
  display: flex;
  align-items: center;
  gap: .5rem;
  flex: none;
}

.exam-duration-control .field {
  inline-size: 5rem;
  padding: .55rem .65rem;
  border: 0;
  border-radius: var(--r-md);
  background: var(--accent-wash);
  color: var(--accent);
  font-family: var(--font-num);
  font-weight: 700;
  text-align: center;
}

.exam-config-options { padding-inline: 1.25rem; }
.exam-config-options .row { padding-block: .9rem; }
.exam-config-options .row + .row { border-block-start: 1px solid var(--rule); }
.exam-config-action { padding: 1.1rem 1.25rem 1.25rem; }
.exam-config-action .btn { inline-size: 100%; min-block-size: 2.9rem; }

.exam-topbar-inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: .5rem;
}

.exam-workspace {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 18rem;
  gap: clamp(1.25rem, 3vw, 2.25rem);
  align-items: start;
  padding-block: clamp(1.25rem, 3vw, 2rem) 4rem;
}

.exam-main-col { min-inline-size: 0; }

.exam-nav-panel {
  position: sticky;
  inset-block-start: 5rem;
  display: grid;
  gap: 1rem;
  padding: 1.15rem;
  border-radius: var(--r-card);
  background: color-mix(in srgb, var(--bg-glass) 94%, transparent);
  box-shadow: none;
}

.exam-nav-heading { align-items: start; }
.exam-nav-panel > .bar { border-radius: var(--r-pill); }
.exam-qgrid { max-block-size: 18rem; overflow-y: auto; padding: 2px; }
.exam-qgrid button { inline-size: 2.45rem; block-size: 2.45rem; border-radius: 9px; }

.exam-grid-legend {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem .85rem;
  color: var(--ink-faint);
  font-size: var(--t-micro);
}

.exam-grid-legend span { display: inline-flex; align-items: center; gap: .35rem; }
.legend-dot { inline-size: .5rem; block-size: .5rem; border-radius: 50%; background: var(--rule); }
.legend-dot.is-done { background: var(--accent); }
.legend-dot.is-flagged { background: var(--spark); }

.exam-nav-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: .65rem;
  padding-block-start: .15rem;
}

.exam-nav-actions .btn-ghost { min-inline-size: 0; padding-inline: .65rem; }

.exam-header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.85rem 1.25rem;
  background: var(--bg-sunk);
  border: 1px solid var(--rule);
  border-radius: var(--r-card);
  box-shadow: var(--shadow-soft-1);
}

.exam-timer-box {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.85rem;
  border-radius: var(--r-pill);
  background: var(--accent-wash);
  border: 0;
  font-family: var(--font-num);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--ink);
}

.exam-timer-box.is-warning {
  color: var(--bad);
  background: var(--bad-wash);
  animation: pulse 1s infinite;
}

/* Result Workspace */
.result-card-hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 50% 0, color-mix(in srgb, var(--accent) 14%, transparent), transparent 48%),
    color-mix(in srgb, var(--bg-glass) 92%, transparent);
  border: 0;
  border-radius: var(--r-card);
  padding: clamp(2rem, 6vw, 3.5rem);
  box-shadow: var(--shadow-soft-1);
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.result-tier { border: 0 !important; border-radius: var(--r-pill) !important; }

.result-score-big {
  font-family: var(--font-num);
  font-size: clamp(3rem, 7vw, 4.5rem);
  font-weight: 800;
  line-height: 1;
  color: var(--accent);
}

.result-breakdown-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  width: 100%;
  max-width: 42rem;
  margin-block: 1rem;
}

.result-breakdown-grid .session-stat-box {
  border: 0;
  border-radius: 0;
  background: transparent;
  padding: .6rem 1rem;
  align-items: center;
}

.result-breakdown-grid .session-stat-box + .session-stat-box {
  border-inline-start: 1px solid var(--rule);
}

.result-review { margin-block-start: clamp(2.25rem, 6vw, 3.5rem); }
.result-wrong-list { display: grid; }

.result-wrong-item {
  display: grid;
  gap: .65rem;
  padding-block: 1.5rem;
  border-block-start: 1px solid var(--rule);
}

.result-wrong-item:last-child { border-block-end: 1px solid var(--rule); }
.result-answer-line { border-radius: var(--r-md); }

/* Responsive cho Study Workspace */
@media (max-width: 56rem) {
  .study-workspace-layout,
  .exam-workspace {
    grid-template-columns: 1fr;
  }
  .session-panel,
  .exam-nav-panel {
    position: static;
  }
  .exam-nav-panel { order: 2; }
  .exam-workspace { padding-block-end: 6.5rem; }
  .exam-nav-actions {
    position: fixed;
    z-index: 35;
    inset-inline: 0;
    inset-block-end: 0;
    padding: .7rem var(--gutter) max(.7rem, env(safe-area-inset-bottom));
    background: color-mix(in srgb, var(--bg-glass) 94%, transparent);
    border-block-start: 1px solid var(--glass-border);
    box-shadow: 0 -8px 24px -18px rgba(18, 30, 42, .5);
    backdrop-filter: blur(16px) saturate(160%);
    -webkit-backdrop-filter: blur(16px) saturate(160%);
  }
  .exam-config-wrap {
    grid-template-columns: 1fr;
    gap: 2rem;
    min-block-size: auto;
  }
  .result-breakdown-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .result-breakdown-grid .session-stat-box:nth-child(3) {
    border-inline-start: 0;
  }
  .result-breakdown-grid .session-stat-box:nth-child(n + 3) {
    border-block-start: 1px solid var(--rule);
  }
}

@media (max-width: 36rem) {
  .answer-option-card {
    padding: 0.85rem;
    gap: 0.65rem;
  }
  .question-meta-row { align-items: flex-start; }
  .study-header-actions { gap: .15rem; }
  .tool-btn span { display: none; }
  .tool-btn { padding-inline: .65rem; }
  .exam-workspace { padding-block-start: 1rem; }
  .exam-config-wrap { padding-block: 2rem 3rem; }
  .exam-config-field { align-items: flex-start; }
  .exam-qgrid { max-block-size: 12rem; }
  .result-card-hero { margin-inline: calc(var(--gutter) * -.35); }
}

/* ==========================================================================
   THEME SIDE DRAWER (NGĂN KÉO TUỲ CHỈNH GIAO DIỆN)
   ========================================================================== */
.drawer-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: 9990;
  opacity: 0;
  transition: opacity var(--motion-drawer);
  pointer-events: none;
}

.drawer-backdrop.is-open {
  opacity: 1;
  pointer-events: auto;
}

.theme-side-drawer {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  inline-size: min(28rem, 90vw);
  background: color-mix(in srgb, var(--color-surface) 92%, transparent);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-left: 1px solid var(--glass-border);
  box-shadow: -8px 0 32px rgba(0, 0, 0, 0.25);
  z-index: 9995;
  display: flex;
  flex-direction: column;
  transform: translate3d(100%, 0, 0);
  transition: transform var(--motion-drawer);
}

.theme-side-drawer.is-open {
  transform: translate3d(0, 0, 0);
}

.drawer-header {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--color-border);
  flex-shrink: 0;
}

.drawer-body {
  padding: 1.5rem;
  overflow-y: auto;
  flex: 1;
}

.drawer-footer {
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--color-border);
  flex-shrink: 0;
  display: flex;
}

.drawer-sec-title {
  font-size: var(--t-micro);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: var(--track-label);
  color: var(--color-muted);
  margin-block-end: 0.65rem;
}

.drawer-grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.5rem;
}

.drawer-grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.5rem;
}

.drawer-pill-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.6rem 0.75rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.88rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--motion-fast);
  min-height: 44px;
}

.drawer-pill-btn:hover {
  background: var(--color-surface-hover);
  border-color: var(--color-muted);
}

.drawer-pill-btn.active {
  background: var(--color-primary-wash);
  border-color: var(--color-primary);
  color: var(--color-primary);
  box-shadow: inset 0 0 0 1px var(--color-primary);
}

.drawer-palette-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.6rem 0.75rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--motion-fast);
  min-height: 44px;
}

.drawer-palette-btn:hover {
  background: var(--color-surface-hover);
}

.drawer-palette-btn.active {
  border-color: var(--color-primary);
  background: var(--color-primary-wash);
  color: var(--color-primary);
}

.palette-swatch {
  inline-size: 1rem;
  block-size: 1rem;
  border-radius: 2px;
  flex-shrink: 0;
}

.drawer-bg-card {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  padding: 0.35rem;
  gap: 0.35rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  cursor: pointer;
  transition: all var(--motion-fast);
}

.drawer-bg-card:hover {
  border-color: var(--color-muted);
}

.drawer-bg-card.active {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 2px var(--color-primary);
}

.drawer-bg-thumb {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  border-radius: 2px;
}

.drawer-bg-name {
  font-size: 0.76rem;
  font-weight: 600;
  text-align: center;
  color: var(--color-text);
}

/* ==========================================================================
   LOADING SKELETON (SHIMMER ANIMATION)
   ========================================================================== */
.skeleton {
  background: linear-gradient(
    90deg,
    color-mix(in srgb, var(--color-text) 8%, transparent) 0%,
    color-mix(in srgb, var(--color-text) 16%, transparent) 50%,
    color-mix(in srgb, var(--color-text) 8%, transparent) 100%
  );
  background-size: 200% 100%;
  animation: skeletonShimmer 1.8s infinite ease-in-out;
  border-radius: var(--radius-sm);
}

@keyframes skeletonShimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.skeleton-card {
  padding: 1.5rem;
  border-radius: var(--radius-card);
  border: 1px solid var(--color-border);
  background: color-mix(in srgb, var(--color-surface) 85%, transparent);
}

/* ==========================================================================
   EMPTY STATE & ERROR STATE
   ========================================================================== */
.empty-state-box,
.error-state-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: clamp(2.5rem, 8vh, 4rem) 1.5rem;
  gap: 0.75rem;
}

.empty-state-icon,
.error-state-icon {
  color: var(--color-muted);
  margin-block-end: 0.5rem;
}

.error-state-icon {
  color: var(--color-error);
}

.empty-state-title,
.error-state-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
}

.empty-state-desc,
.error-state-msg {
  max-width: 28rem;
  color: var(--color-muted);
  line-height: var(--lh-read);
}

/* ==========================================================================
   PROGRESS RING SVG
   ========================================================================== */
.progress-ring-wrap {
  position: relative;
  display: inline-grid;
  place-items: center;
}

.progress-ring-label {
  position: absolute;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--color-text);
}

/* ==========================================================================
   MOBILE FLOATING BOTTOM BAR
   ========================================================================== */
.mobile-floating-bar {
  display: none;
  position: fixed;
  bottom: 1rem;
  left: 50%;
  transform: translateX(-50%);
  width: calc(100% - 2rem);
  max-width: 24rem;
  height: 3.8rem;
  background: color-mix(in srgb, var(--color-surface) 88%, transparent);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.28);
  border-radius: var(--radius-pill);
  z-index: 8000;
  align-items: center;
  justify-content: space-around;
  padding: 0 0.5rem;
}

.mobile-nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.2rem;
  color: var(--color-muted);
  text-decoration: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.35rem 0.65rem;
  min-width: 44px;
  min-height: 44px;
  border-radius: var(--radius-sm);
  transition: color var(--motion-fast);
}

.mobile-nav-item:hover,
.mobile-nav-item.active {
  color: var(--color-primary);
}

.mobile-nav-label {
  font-size: 0.72rem;
  font-weight: 600;
}

@media (max-width: 48rem) {
  .app-layout {
    display: block;
  }
  .topbar-left {
    max-width: none;
  }
  .topbar-search, .dashboard-search {
    max-width: 100%;
  }
  .mobile-floating-bar {
    display: flex;
  }
  body {
    padding-bottom: 5.5rem;
  }
  .nav-tabs-pill {
    display: none;
  }
}

@media (max-width: 48rem) {
  .study-chart-value { font-size: 26px; }
  .study-chart-label { font-size: 22px; }
  .dashboard-search {
    inline-size: auto;
    flex: 1 1 0;
    min-inline-size: 0;
  }
  .search-input { min-inline-size: 0; }
  .hide-mobile { display: none !important; }
  .study-nav-bar > .btn { flex: 1 1 0; justify-content: center; }
}

@media (max-width: 32rem) {
  .topbar-brand .brand-text {
    display: none;
  }
  /* Màn hẹp: ô tìm kiếm thu thành một nút kính lúp, bấm vẫn mở tìm nhanh */
  .topbar-search, .dashboard-search {
    flex: none;
    inline-size: 2.4rem;
  }
  .topbar-search .search-input, .dashboard-search .search-input {
    padding: 0;
    color: transparent;
    caret-color: transparent;
    cursor: pointer;
  }
  .topbar-search .search-input::placeholder,
  .dashboard-search .search-input::placeholder { color: transparent; }
  .topbar-search > .ico, .dashboard-search > .ico {
    inset-inline-start: 50%;
    transform: translateX(-50%);
  }
  .search-cmd-badge { display: none; }
  .topbar-left, .topbar-right { gap: .3rem !important; }
}

/* ==========================================================================
   REDUCED MOTION (PREFERS-REDUCED-MOTION)
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .ambient-scenic-img {
    transform: none !important;
  }
}


/* Nút đồng bộ Google Drive ở góc thanh đầu */
.sync-btn { transition: color var(--dur-fast); }
.sync-btn.is-spinning .ico { animation: sync-spin 1s linear infinite; }
@keyframes sync-spin { to { transform: rotate(360deg); } }
@media (prefers-reduced-motion: reduce) {
  .sync-btn.is-spinning .ico { animation: none; opacity: .5; }
}