:root {
  --app-body-bg: #f4efe8;
  --app-body-glow: rgba(24, 86, 78, 0.08);
  --app-panel-bg: rgba(255, 252, 247, 0.84);
  --app-panel-bg-strong: #fffdf9;
  --app-panel-muted: rgba(244, 238, 229, 0.88);
  --app-border: rgba(33, 27, 22, 0.1);
  --app-border-strong: rgba(33, 27, 22, 0.16);
  --app-ink: #1b1815;
  --app-muted: #6d655d;
  --app-muted-soft: #8f857d;
  --app-accent: #1f645c;
  --app-accent-strong: #164942;
  --app-accent-soft: rgba(31, 100, 92, 0.11);
  --app-success: #2f6f5c;
  --app-success-soft: rgba(47, 111, 92, 0.12);
  --app-warning: #a06d1d;
  --app-warning-soft: rgba(160, 109, 29, 0.12);
  --app-danger: #93493d;
  --app-danger-soft: rgba(147, 73, 61, 0.12);
  --app-shadow-sm: 0 14px 32px rgba(32, 23, 13, 0.08);
  --app-shadow-lg: 0 24px 60px rgba(32, 23, 13, 0.1);
  --app-radius-lg: 28px;
  --app-radius-md: 22px;
  --app-radius-sm: 16px;
  --app-radius-pill: 999px;
}

[data-bs-theme="dark"] {
  --app-body-bg: #14181b;
  --app-body-glow: rgba(49, 139, 129, 0.15);
  --app-panel-bg: rgba(23, 29, 32, 0.86);
  --app-panel-bg-strong: #1b2327;
  --app-panel-muted: rgba(28, 36, 41, 0.92);
  --app-border: rgba(229, 223, 214, 0.08);
  --app-border-strong: rgba(229, 223, 214, 0.15);
  --app-ink: #f2ece4;
  --app-muted: #b0a79f;
  --app-muted-soft: #867d76;
  --app-accent: #69b8ab;
  --app-accent-strong: #9ed7ce;
  --app-accent-soft: rgba(105, 184, 171, 0.14);
  --app-success: #86c7aa;
  --app-success-soft: rgba(134, 199, 170, 0.16);
  --app-warning: #e0ba73;
  --app-warning-soft: rgba(224, 186, 115, 0.16);
  --app-danger: #d5968a;
  --app-danger-soft: rgba(213, 150, 138, 0.16);
  --app-shadow-sm: 0 18px 38px rgba(0, 0, 0, 0.28);
  --app-shadow-lg: 0 28px 80px rgba(0, 0, 0, 0.34);
}

.app-shell,
.flashcard-app-shell {
  min-height: 100vh;
  background:
    radial-gradient(circle at top right, var(--app-body-glow), transparent 32%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.45), transparent 28%),
    var(--app-body-bg);
  color: var(--app-ink);
}

[data-bs-theme="dark"] .app-shell,
[data-bs-theme="dark"] .flashcard-app-shell {
  background:
    radial-gradient(circle at top right, var(--app-body-glow), transparent 34%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.02), transparent 18%),
    var(--app-body-bg);
}

.app-body,
.flashcard-app-main {
  padding-bottom: 4rem;
}

.app-navbar {
  position: sticky;
  top: 0;
  z-index: 1030;
  padding: 0.9rem 0;
  background: rgba(252, 249, 244, 0.76);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--app-border);
}

[data-bs-theme="dark"] .app-navbar {
  background: rgba(20, 24, 27, 0.8);
}

.app-navbar .container-fluid {
  padding-left: clamp(1rem, 2vw, 2rem);
  padding-right: clamp(1rem, 2vw, 2rem);
}

.app-brand {
  display: inline-flex;
  align-items: center;
}

.app-nav-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.65rem 0.9rem;
  border-radius: var(--app-radius-pill);
  color: var(--app-muted);
  font-size: 0.94rem;
  font-weight: 600;
  text-decoration: none;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.app-nav-link:hover,
.app-nav-link:focus {
  background: rgba(255, 255, 255, 0.7);
  color: var(--app-ink);
}

[data-bs-theme="dark"] .app-nav-link:hover,
[data-bs-theme="dark"] .app-nav-link:focus {
  background: rgba(255, 255, 255, 0.05);
}

.app-nav-link.is-active {
  background: var(--app-accent-soft);
  color: var(--app-accent-strong);
}

.app-navbar .dropdown-menu {
  border: 1px solid var(--app-border);
  background: var(--app-panel-bg-strong);
  box-shadow: var(--app-shadow-sm);
  border-radius: var(--app-radius-sm);
}

.app-navbar .dropdown-item {
  color: var(--app-ink);
  border-radius: 12px;
}

.app-navbar .dropdown-item:hover,
.app-navbar .dropdown-item:focus,
.app-navbar .dropdown-item.active {
  background: var(--app-accent-soft);
  color: var(--app-accent-strong);
}

.app-navbar .btn-light,
.app-navbar .btn-icon,
.app-navbar .rounded-circle {
  color: var(--app-ink);
}

.app-page-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.app-page-eyebrow,
.app-section-label {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.85rem;
  color: var(--app-accent);
  font-size: 0.74rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.app-page-title {
  margin-bottom: 0.65rem;
  font-size: clamp(2.1rem, 4vw, 3.2rem);
  letter-spacing: -0.05em;
}

.app-page-subtitle {
  max-width: 44rem;
  margin-bottom: 0;
  color: var(--app-muted);
  font-size: 1.04rem;
  line-height: 1.7;
}

.app-panel,
.app-shell .card,
.flashcard-app-shell .card {
  border: 1px solid var(--app-border);
  border-radius: var(--app-radius-md);
  background: var(--app-panel-bg);
  box-shadow: var(--app-shadow-sm);
}

.app-shell .text-primary,
.flashcard-app-shell .text-primary {
  color: var(--app-accent) !important;
}

.app-shell .text-success,
.flashcard-app-shell .text-success {
  color: var(--app-success) !important;
}

.app-shell .text-warning,
.flashcard-app-shell .text-warning {
  color: var(--app-warning) !important;
}

.app-shell .text-danger,
.flashcard-app-shell .text-danger {
  color: var(--app-danger) !important;
}

.app-shell .bg-danger,
.flashcard-app-shell .bg-danger {
  background-color: var(--app-danger) !important;
}

.app-panel {
  padding: 1.5rem;
}

.app-panel-muted {
  background: var(--app-panel-muted);
}

.app-panel-accent {
  background:
    linear-gradient(135deg, rgba(31, 100, 92, 0.06), transparent 45%),
    var(--app-panel-bg);
}

.app-shell .card-header,
.flashcard-app-shell .card-header {
  padding: 1.5rem 1.5rem 0;
  border-bottom: 0;
  background: transparent !important;
  color: inherit !important;
}

.app-shell .card-body,
.flashcard-app-shell .card-body {
  padding: 1.5rem;
}

.app-shell .list-group-item,
.flashcard-app-shell .list-group-item {
  border-color: var(--app-border);
  background: transparent;
}

.app-panel-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.app-panel-title {
  margin-bottom: 0.35rem;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--app-ink);
}

.app-panel-copy {
  margin-bottom: 0;
  color: var(--app-muted);
  line-height: 1.7;
}

.app-icon-chip {
  width: 2.75rem;
  height: 2.75rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  background: var(--app-accent-soft);
  color: var(--app-accent-strong);
  flex-shrink: 0;
}

.app-icon-chip.is-warning {
  background: var(--app-warning-soft);
  color: var(--app-warning);
}

.app-icon-chip.is-danger {
  background: var(--app-danger-soft);
  color: var(--app-danger);
}

.app-meta-row,
.app-chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.app-chip,
.app-shell .badge,
.flashcard-app-shell .badge {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.4rem 0.75rem;
  border-radius: var(--app-radius-pill);
  background: rgba(255, 255, 255, 0.74);
  border: 1px solid var(--app-border);
  color: var(--app-muted);
  font-size: 0.78rem;
  font-weight: 600;
}

[data-bs-theme="dark"] .app-chip,
[data-bs-theme="dark"] .app-shell .badge,
[data-bs-theme="dark"] .flashcard-app-shell .badge {
  background: rgba(255, 255, 255, 0.05);
}

.app-shell .form-label,
.flashcard-app-shell .form-label {
  color: var(--app-muted);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.app-shell .form-control,
.app-shell .form-select,
.flashcard-app-shell .form-control,
.flashcard-app-shell .form-select {
  min-height: 3.2rem;
  border: 1px solid var(--app-border);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.72);
  color: var(--app-ink);
  box-shadow: none;
}

[data-bs-theme="dark"] .app-shell .form-control,
[data-bs-theme="dark"] .app-shell .form-select,
[data-bs-theme="dark"] .flashcard-app-shell .form-control,
[data-bs-theme="dark"] .flashcard-app-shell .form-select {
  background: rgba(255, 255, 255, 0.04);
}

.app-shell textarea.form-control,
.flashcard-app-shell textarea.form-control {
  min-height: 10rem;
}

.app-shell .form-control:focus,
.app-shell .form-select:focus,
.flashcard-app-shell .form-control:focus,
.flashcard-app-shell .form-select:focus {
  border-color: rgba(31, 100, 92, 0.38);
  box-shadow: 0 0 0 0.25rem rgba(31, 100, 92, 0.1);
}

.app-shell .form-text,
.flashcard-app-shell .form-text,
.app-muted-text {
  color: var(--app-muted-soft);
}

.app-shell .btn,
.flashcard-app-shell .btn,
.app-btn {
  border-radius: var(--app-radius-pill);
  font-weight: 600;
  padding: 0.8rem 1.1rem;
  box-shadow: none;
}

.app-shell .btn-primary,
.app-shell .btn-success,
.flashcard-app-shell .btn-primary,
.app-btn-primary {
  background: var(--app-accent);
  border-color: var(--app-accent);
  color: #f7f4ef;
}

.app-shell .btn-primary:hover,
.app-shell .btn-success:hover,
.flashcard-app-shell .btn-primary:hover,
.app-btn-primary:hover {
  background: var(--app-accent-strong);
  border-color: var(--app-accent-strong);
  color: #f7f4ef;
}

.app-shell .btn-outline-primary,
.app-shell .btn-outline-secondary,
.app-shell .btn-secondary,
.flashcard-app-shell .btn-outline-primary,
.flashcard-app-shell .btn-outline-secondary,
.flashcard-app-shell .btn-secondary,
.app-btn-secondary {
  background: transparent;
  border-color: var(--app-border-strong);
  color: var(--app-ink);
}

.app-shell .btn-outline-primary:hover,
.app-shell .btn-outline-secondary:hover,
.app-shell .btn-secondary:hover,
.flashcard-app-shell .btn-outline-primary:hover,
.flashcard-app-shell .btn-outline-secondary:hover,
.flashcard-app-shell .btn-secondary:hover,
.app-btn-secondary:hover {
  background: rgba(255, 255, 255, 0.7);
  border-color: var(--app-border-strong);
  color: var(--app-ink);
}

[data-bs-theme="dark"] .app-shell .btn-outline-primary:hover,
[data-bs-theme="dark"] .app-shell .btn-outline-secondary:hover,
[data-bs-theme="dark"] .app-shell .btn-secondary:hover,
[data-bs-theme="dark"] .flashcard-app-shell .btn-outline-primary:hover,
[data-bs-theme="dark"] .flashcard-app-shell .btn-outline-secondary:hover,
[data-bs-theme="dark"] .flashcard-app-shell .btn-secondary:hover,
[data-bs-theme="dark"] .app-btn-secondary:hover {
  background: rgba(255, 255, 255, 0.05);
}

.app-shell .btn-warning,
.app-btn-warning {
  background: var(--app-warning-soft);
  border-color: transparent;
  color: var(--app-warning);
}

.app-shell .btn-warning:hover,
.app-btn-warning:hover {
  background: rgba(160, 109, 29, 0.2);
  color: var(--app-warning);
}

.app-shell .btn-light-success,
.flashcard-app-shell .btn-light-success {
  background: var(--app-success-soft);
  border-color: transparent;
  color: var(--app-success);
}

.app-shell .btn-light-danger,
.flashcard-app-shell .btn-light-danger {
  background: var(--app-danger-soft);
  border-color: transparent;
  color: var(--app-danger);
}

.app-shell .btn-light-info,
.flashcard-app-shell .btn-light-info,
.app-btn-soft {
  background: var(--app-accent-soft);
  border-color: transparent;
  color: var(--app-accent-strong);
}

.app-kpi-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 1rem;
}

.app-kpi-card {
  padding: 1.35rem;
  border: 1px solid var(--app-border);
  border-radius: var(--app-radius-sm);
  background: rgba(255, 255, 255, 0.62);
}

[data-bs-theme="dark"] .app-kpi-card {
  background: rgba(255, 255, 255, 0.04);
}

.app-kpi-label {
  display: block;
  margin-bottom: 0.45rem;
  color: var(--app-muted);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.app-kpi-value {
  font-size: clamp(1.55rem, 3vw, 2.2rem);
  line-height: 1;
  letter-spacing: -0.05em;
  font-weight: 700;
  color: var(--app-ink);
}

.app-inline-stat {
  min-width: 90px;
}

.app-inline-stat .app-kpi-value {
  font-size: 1.5rem;
}

.app-progress-track,
.app-shell .progress,
.flashcard-app-shell .progress {
  height: 0.55rem;
  overflow: hidden;
  border-radius: var(--app-radius-pill);
  background: rgba(34, 29, 22, 0.08);
}

.app-shell .progress-bar,
.flashcard-app-shell .progress-bar {
  background: linear-gradient(90deg, var(--app-accent-strong), var(--app-accent));
}

.app-list-row {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 0;
  border-top: 1px solid var(--app-border);
}

.app-list-row:first-child {
  border-top: 0;
  padding-top: 0;
}

.app-list-row:last-child {
  padding-bottom: 0;
}

.app-list-title {
  margin-bottom: 0.2rem;
  font-size: 1rem;
  font-weight: 700;
}

.app-list-copy {
  margin-bottom: 0;
  color: var(--app-muted);
}

.app-shell .table,
.flashcard-app-shell .table {
  color: var(--app-ink);
  margin-bottom: 0;
  --bs-table-bg: transparent;
  --bs-table-hover-bg: rgba(31, 100, 92, 0.04);
}

.app-shell .table thead th,
.flashcard-app-shell .table thead th {
  padding: 1rem 1.1rem;
  background: rgba(255, 255, 255, 0.68);
  border-bottom: 1px solid var(--app-border);
  color: var(--app-muted);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

[data-bs-theme="dark"] .app-shell .table thead th,
[data-bs-theme="dark"] .flashcard-app-shell .table thead th {
  background: rgba(255, 255, 255, 0.04);
}

.app-shell .table td,
.flashcard-app-shell .table td {
  padding: 1rem 1.1rem;
  border-color: var(--app-border);
  vertical-align: middle;
}

.app-shell .table-active,
.flashcard-app-shell .table-active {
  --bs-table-active-bg: rgba(31, 100, 92, 0.08);
}

.app-table-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.app-table-actions .btn,
.app-table-actions form {
  margin: 0;
}

.app-pill-note {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.55rem 0.8rem;
  border-radius: var(--app-radius-pill);
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--app-border);
  color: var(--app-muted);
  font-size: 0.86rem;
}

.app-chart-card {
  height: 100%;
}

.app-filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
  align-items: center;
  justify-content: space-between;
}

.app-empty-state {
  padding: 3rem 1.5rem;
  text-align: center;
}

.app-empty-state-icon {
  width: 4.5rem;
  height: 4.5rem;
  margin: 0 auto 1.25rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--app-accent-soft);
  color: var(--app-accent-strong);
  font-size: 1.45rem;
}

.app-code-surface {
  border: 1px solid rgba(17, 21, 26, 0.7);
  border-radius: var(--app-radius-md);
  background: linear-gradient(180deg, rgba(17, 21, 26, 0.94), rgba(20, 26, 31, 0.98));
  box-shadow: var(--app-shadow-lg);
  color: #f3ede5;
}

.app-code-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1.25rem 0;
}

.app-dot-group {
  display: inline-flex;
  gap: 0.35rem;
}

.app-dot {
  width: 0.7rem;
  height: 0.7rem;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.18);
}

.app-code-meta {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  color: rgba(243, 237, 229, 0.74);
  font-size: 0.85rem;
}

.app-code-hint {
  color: rgba(243, 237, 229, 0.74);
}

.app-shell #code-display,
.app-shell #demo-code-display {
  font-family: "SF Mono", "Fira Code", "Cascadia Code", Consolas, monospace;
  white-space: pre-wrap;
  word-wrap: break-word;
  user-select: none;
  line-height: 1.8;
  letter-spacing: 0.02em;
  color: #f6efe8;
}

.app-shell .typing-pending {
  color: rgba(246, 239, 232, 0.56);
}

.app-shell #typing-input,
.app-shell #demo-typing-input {
  font-size: 16px;
}

.app-shell .typing-correct {
  background: rgba(96, 182, 153, 0.14);
  color: #f6efe8;
  border-radius: 4px;
}

.app-shell .typing-incorrect {
  background: rgba(220, 113, 98, 0.18);
  color: #ffb3a7;
  text-decoration: underline wavy #ff8f7e;
  text-underline-offset: 4px;
  border-radius: 4px;
}

.app-shell .typing-cursor {
  background: rgba(128, 203, 192, 0.16);
  border-left: 2px solid #9ed7ce;
}

.app-shell .fg-container {
  max-width: 100%;
}

.fg-key rect {
  fill: #f5f5f5;
  stroke: #d5d5d5;
  stroke-width: 1;
  transition: fill 0.1s ease, stroke 0.1s ease;
}

.fg-key text {
  pointer-events: none;
  transition: fill 0.1s ease;
}

.fg-finger {
  fill: #d5d5d5;
  stroke: #c0c0c0;
  stroke-width: 0.5;
  transition: fill 0.1s ease, filter 0.1s ease;
}

.fg-palm {
  fill: #e8e8e8;
  stroke: none;
  opacity: 0.6;
}

.fg-key.fg-green rect {
  fill: #5ea28d;
  stroke: #4d8c79;
}

.fg-key.fg-green text,
.fg-key.fg-red text {
  fill: #fff !important;
}

.fg-finger.fg-green {
  fill: #5ea28d;
  filter: drop-shadow(0 0 4px rgba(94, 162, 141, 0.45));
}

.fg-key.fg-yellow rect {
  fill: #d9b45f;
  stroke: #be973f;
}

.fg-key.fg-yellow text {
  fill: #33291d !important;
}

.fg-finger.fg-yellow {
  fill: #d9b45f;
  filter: drop-shadow(0 0 4px rgba(217, 180, 95, 0.45));
}

.fg-key.fg-red rect {
  fill: #cf7d70;
  stroke: #b96859;
}

.fg-finger.fg-red {
  fill: #cf7d70;
  filter: drop-shadow(0 0 4px rgba(207, 125, 112, 0.45));
}

.fg-shift-indicator {
  text-align: center;
  height: 22px;
  margin-top: 2px;
  visibility: hidden;
  opacity: 0;
  transition: opacity 0.15s ease;
}

.fg-shift-indicator.fg-shift-active {
  visibility: visible;
  opacity: 1;
}

.fg-shift-badge {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 999px;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.05em;
  background: #78909c;
  color: #fff;
}

[data-bs-theme="dark"] .fg-key rect {
  fill: #253038;
  stroke: #43515c;
}

[data-bs-theme="dark"] .fg-key text {
  fill: #d8d2ca;
}

[data-bs-theme="dark"] .fg-finger {
  fill: #4a5660;
  stroke: #55616c;
}

[data-bs-theme="dark"] .fg-palm {
  fill: #39434b;
}

.app-study-layout {
  width: calc(100% - 2rem);
  max-width: 1180px;
  margin: 0 auto;
  padding: 2rem 0 4rem;
}

.app-study-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 1.5rem;
}

.app-study-card {
  padding: 1.5rem;
  min-height: 100%;
}

.app-study-toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  align-items: center;
  justify-content: space-between;
}

.app-study-actions,
.app-study-utility-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-items: center;
}

.app-study-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  align-items: center;
}

.app-study-copy {
  max-width: 45rem;
}

.app-study-body {
  min-height: 15rem;
  padding: 1.25rem;
  border-radius: var(--app-radius-sm);
  border: 1px solid var(--app-border);
  background: rgba(255, 255, 255, 0.62);
}

[data-bs-theme="dark"] .app-study-body {
  background: rgba(255, 255, 255, 0.04);
}

.app-study-body code,
.app-study-body pre {
  margin: 0;
  font-family: "SF Mono", "Fira Code", "Cascadia Code", Consolas, monospace;
  font-size: 0.96rem;
  line-height: 1.75;
  white-space: pre-wrap;
  word-break: break-word;
  color: inherit;
}

.app-study-question {
  font-size: 1.05rem;
}

.app-answer-reveal {
  margin-top: 1rem;
}

.app-control-grid,
.app-grade-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
}

.app-study-controls {
  margin-top: 1rem;
}

.app-study-helper {
  color: var(--app-muted);
  font-size: 0.92rem;
}

.app-flashcard-select {
  min-width: 220px;
}

.blur {
  filter: blur(12px);
}

.app-table-summary {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.25rem;
  color: var(--app-muted);
}

.app-home-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--app-muted);
  text-decoration: none;
  font-weight: 600;
}

.app-home-link:hover {
  color: var(--app-ink);
}

.app-home-hero {
  position: relative;
  overflow: hidden;
  padding: 2rem;
  background:
    radial-gradient(circle at top right, rgba(31, 100, 92, 0.14), transparent 35%),
    linear-gradient(160deg, rgba(255, 255, 255, 0.78), rgba(246, 239, 230, 0.88)),
    var(--app-panel-bg);
}

[data-bs-theme="dark"] .app-home-hero {
  background:
    radial-gradient(circle at top right, rgba(105, 184, 171, 0.18), transparent 38%),
    linear-gradient(160deg, rgba(27, 35, 39, 0.92), rgba(21, 27, 30, 0.92)),
    var(--app-panel-bg);
}

.app-home-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(120deg, transparent 0%, rgba(255, 255, 255, 0.18) 30%, transparent 55%);
  pointer-events: none;
}

.app-home-hero-content {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.app-home-profile {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.app-home-avatar {
  width: 4.75rem;
  height: 4.75rem;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid rgba(255, 255, 255, 0.9);
  box-shadow: 0 18px 36px rgba(31, 100, 92, 0.16);
}

.app-home-name {
  margin-bottom: 0.35rem;
  font-size: clamp(1.75rem, 4vw, 2.35rem);
  letter-spacing: -0.05em;
}

.app-home-copy {
  margin-bottom: 0;
  color: var(--app-muted);
  line-height: 1.7;
}

.app-home-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-items: center;
}

.app-tab-nav {
  gap: 0.65rem;
  border-bottom: 0;
}

.app-tab-nav .nav-link {
  border: 1px solid var(--app-border);
  border-radius: var(--app-radius-pill);
  color: var(--app-muted);
  background: rgba(255, 255, 255, 0.58);
  font-weight: 600;
  padding: 0.75rem 1rem;
}

[data-bs-theme="dark"] .app-tab-nav .nav-link {
  background: rgba(255, 255, 255, 0.04);
}

.app-tab-nav .nav-link.active,
.app-tab-nav .nav-link:hover,
.app-tab-nav .nav-link:focus {
  background: var(--app-accent-soft);
  border-color: rgba(31, 100, 92, 0.18);
  color: var(--app-accent-strong);
}

.app-tab-pane-shell {
  margin-top: 1.5rem;
}

.app-upload-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(240px, 0.78fr);
  gap: 1.5rem;
  align-items: start;
}

.app-upload-form,
.app-upload-notes {
  height: 100%;
}

.app-upload-notes-list {
  margin: 0;
  padding-left: 1rem;
  color: var(--app-muted);
}

.app-upload-notes-list li + li {
  margin-top: 0.7rem;
}

.app-radio-stack {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.app-radio-card {
  display: flex;
  align-items: flex-start;
  gap: 0.85rem;
  padding: 1rem 1.1rem;
  border: 1px solid var(--app-border);
  border-radius: var(--app-radius-sm);
  background: rgba(255, 255, 255, 0.5);
}

[data-bs-theme="dark"] .app-radio-card {
  background: rgba(255, 255, 255, 0.03);
}

.app-radio-card .form-check-input {
  margin-top: 0.15rem;
}

.app-radio-card-title {
  margin-bottom: 0.2rem;
  font-weight: 700;
}

.app-radio-card-copy {
  margin-bottom: 0;
  color: var(--app-muted);
  font-size: 0.92rem;
}

.app-resource-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1.25rem;
}

.app-resource-card {
  display: flex;
  flex-direction: column;
  min-height: 100%;
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.app-resource-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--app-shadow-lg);
  border-color: rgba(31, 100, 92, 0.16);
}

.app-resource-card-media {
  min-height: 124px;
  background:
    radial-gradient(circle at top right, rgba(31, 100, 92, 0.18), transparent 38%),
    linear-gradient(135deg, rgba(31, 100, 92, 0.12), rgba(255, 255, 255, 0.3)),
    rgba(244, 238, 229, 0.85);
  border-bottom: 1px solid var(--app-border);
  display: flex;
  align-items: stretch;
  justify-content: center;
  overflow: hidden;
}

[data-bs-theme="dark"] .app-resource-card-media {
  background:
    radial-gradient(circle at top right, rgba(105, 184, 171, 0.18), transparent 36%),
    linear-gradient(135deg, rgba(105, 184, 171, 0.14), rgba(255, 255, 255, 0.02)),
    rgba(255, 255, 255, 0.03);
}

.app-resource-card-media img {
  width: 100%;
  height: 124px;
  object-fit: cover;
}

.app-resource-card-body {
  padding: 1.25rem;
  flex: 1;
}

.app-resource-card-title {
  margin-bottom: 0.55rem;
  font-size: 1.1rem;
  line-height: 1.35;
}

.app-resource-card-title a {
  color: var(--app-ink);
  text-decoration: none;
}

.app-resource-card-title a:hover {
  color: var(--app-accent-strong);
}

.app-resource-card-copy {
  margin-bottom: 0;
  color: var(--app-muted);
}

.app-resource-card-footer {
  padding: 0 1.25rem 1.25rem;
}

.app-resource-card-footer .btn {
  width: 100%;
}

.app-resource-card-note {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 0.75rem;
  border-radius: var(--app-radius-pill);
  background: rgba(255, 255, 255, 0.64);
  border: 1px solid var(--app-border);
  color: var(--app-muted);
  font-size: 0.84rem;
  font-weight: 600;
}

[data-bs-theme="dark"] .app-resource-card-note {
  background: rgba(255, 255, 255, 0.04);
}

.app-upload-action-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
  align-items: center;
}

@media (max-width: 991px) {
  .app-page-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .app-study-grid {
    grid-template-columns: 1fr;
  }

  .app-upload-layout {
    grid-template-columns: 1fr;
  }

  .app-navbar .navbar-collapse {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--app-border);
  }
}

@media (max-width: 767px) {
  .app-panel,
  .app-shell .card-body,
  .flashcard-app-shell .card-body {
    padding: 1.2rem;
  }

  .app-kpi-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .app-study-layout {
    width: calc(100% - 1rem);
  }

  .app-list-row,
  .app-filter-bar,
  .app-study-toolbar,
  .app-home-hero-content {
    flex-direction: column;
    align-items: stretch;
  }

  .app-table-actions {
    flex-direction: column;
  }
}