/* ==========================================================================
   StudyBuddy - Modern Styling & Design System
   ========================================================================== */

:root {
  /* Light Theme */
  --font-main: 'Plus Jakarta Sans', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --bg-app: #f4f6fb;
  --bg-card: #ffffff;
  --bg-card-subtle: #f8fafc;
  --border-color: #e2e8f0;
  --border-focus: #4f46e5;
  
  --text-main: #0f172a;
  --text-muted: #64748b;
  --text-light: #94a3b8;

  --primary: #4f46e5;
  --primary-hover: #4338ca;
  --primary-light: #eef2ff;
  --primary-text: #ffffff;

  --secondary: #0ea5e9;
  --secondary-hover: #0284c7;

  --success: #10b981;
  --success-light: #ecfdf5;
  --warning: #f59e0b;
  --warning-light: #fffbeb;
  --danger: #ef4444;
  --danger-light: #fef2f2;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 12px 24px -4px rgba(0, 0, 0, 0.08), 0 4px 8px -4px rgba(0, 0, 0, 0.03);
  --shadow-card: 0 10px 30px -5px rgba(79, 70, 229, 0.07);

  --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

body.theme-dark {
  --bg-app: #0b0f19;
  --bg-card: #131b2e;
  --bg-card-subtle: #1a243c;
  --border-color: #24304f;
  --border-focus: #6366f1;

  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-light: #64748b;

  --primary: #6366f1;
  --primary-hover: #818cf8;
  --primary-light: rgba(99, 102, 241, 0.15);
  --primary-text: #ffffff;

  --secondary: #38bdf8;
  --secondary-hover: #0ea5e9;

  --success: #34d399;
  --success-light: rgba(52, 211, 153, 0.15);
  --warning: #fbbf24;
  --warning-light: rgba(251, 191, 36, 0.15);
  --danger: #f87171;
  --danger-light: rgba(248, 113, 113, 0.15);

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 14px 28px -4px rgba(0, 0, 0, 0.5);
  --shadow-card: 0 10px 30px -5px rgba(0, 0, 0, 0.5);
}

/* Base Reset */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-main);
  background-color: var(--bg-app);
  color: var(--text-main);
  line-height: 1.5;
  min-height: 100vh;
  transition: background-color 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
}

/* Layout */
.app-layout {
  max-width: 1040px;
  margin: 0 auto;
  padding: 1.25rem 1rem 3rem 1rem;
}

/* Header */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 1.25rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.brand-icon {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 12px rgba(79, 70, 229, 0.3);
}

.brand-title {
  font-size: 1.45rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--text-main), var(--primary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.brand-subtitle {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

/* Nav Tabs */
.nav-tabs {
  display: flex;
  background-color: var(--bg-card);
  padding: 0.3rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  gap: 0.25rem;
}

.nav-tab {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.5rem 1.1rem;
  border-radius: var(--radius-full);
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-family: var(--font-main);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.nav-tab:hover {
  color: var(--text-main);
}

.nav-tab.active {
  background-color: var(--primary);
  color: var(--primary-text);
  box-shadow: 0 2px 8px rgba(79, 70, 229, 0.35);
}

/* Header Action Buttons */
.header-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.icon-btn {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-color);
  background-color: var(--bg-card);
  color: var(--text-main);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 1.1rem;
  transition: var(--transition);
}

.icon-btn:hover {
  background-color: var(--bg-card-subtle);
  border-color: var(--primary);
  transform: translateY(-1px);
}

body.theme-light .icon-sun { display: none; }
body.theme-dark .icon-moon { display: none; }

/* Stats Bar */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0.85rem;
  margin-bottom: 1.75rem;
}

.stat-pill {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 0.75rem 1rem;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.stat-pill:hover {
  border-color: var(--primary);
  transform: translateY(-1px);
}

.stat-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  font-weight: 600;
}

.stat-value {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-main);
  margin-top: 0.2rem;
  font-family: var(--font-mono);
}

/* Views Management */
.view-panel {
  display: none;
  animation: fadeIn 0.25s ease-out;
}

.view-panel.active {
  display: block;
}

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

/* Cards & Generic Components */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: var(--shadow-card);
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.35rem;
}

.card-subtitle {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: var(--font-main);
  font-size: 0.92rem;
  font-weight: 600;
  padding: 0.65rem 1.25rem;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: var(--transition);
  user-select: none;
}

.btn:active {
  transform: scale(0.98);
}

.btn-large {
  padding: 0.85rem 2rem;
  font-size: 1.05rem;
}

.btn-sm {
  padding: 0.4rem 0.85rem;
  font-size: 0.82rem;
  border-radius: var(--radius-sm);
}

.btn-primary {
  background-color: var(--primary);
  color: var(--primary-text);
  box-shadow: 0 4px 14px rgba(79, 70, 229, 0.3);
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  box-shadow: 0 6px 18px rgba(79, 70, 229, 0.4);
}

.btn-secondary {
  background-color: var(--secondary);
  color: #fff;
}

.btn-secondary:hover {
  background-color: var(--secondary-hover);
}

.btn-outline {
  background-color: transparent;
  border-color: var(--border-color);
  color: var(--text-main);
}

.btn-outline:hover {
  background-color: var(--bg-card-subtle);
  border-color: var(--text-muted);
}

.btn-success {
  background-color: var(--success);
  color: #ffffff;
}

.btn-warning {
  background-color: var(--warning);
  color: #ffffff;
}

.btn-link {
  background: none;
  border: none;
  color: var(--text-muted);
  font-family: var(--font-main);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  padding: 0.25rem 0.5rem;
  transition: var(--transition);
}

.btn-link:hover {
  color: var(--primary);
}

.btn-danger-link:hover {
  color: var(--danger);
}

.btn-accent-link {
  color: var(--primary);
}

/* ==========================================================================
   1. POMODORO VIEW STYLES
   ========================================================================== */

.pomodoro-grid {
  display: grid;
  grid-template-columns: 1.35fr 1fr;
  gap: 1.5rem;
}

.timer-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.timer-mode-selector {
  display: flex;
  background-color: var(--bg-card-subtle);
  padding: 0.3rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-color);
  gap: 0.3rem;
  margin-bottom: 1.5rem;
}

.mode-pill {
  padding: 0.45rem 0.95rem;
  border-radius: var(--radius-full);
  border: none;
  background: transparent;
  font-family: var(--font-main);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: var(--transition);
}

.mode-pill.active {
  background-color: var(--bg-card);
  color: var(--primary);
  box-shadow: var(--shadow-sm);
  font-weight: 700;
}

/* Circular Timer */
.timer-visual-container {
  position: relative;
  width: 260px;
  height: 260px;
  margin: 0.5rem auto 1.5rem auto;
}

.progress-ring {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.progress-ring-bg {
  fill: none;
  stroke: var(--border-color);
  stroke-width: 10;
}

.progress-ring-circle {
  fill: none;
  stroke: var(--primary);
  stroke-width: 10;
  stroke-linecap: round;
  stroke-dasharray: 691.15; /* 2 * PI * 110 */
  stroke-dashoffset: 0;
  transition: stroke-dashoffset 0.85s linear, stroke 0.3s ease;
}

.timer-display-inner {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.timer-status-badge {
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--primary);
  background-color: var(--primary-light);
  padding: 0.2rem 0.75rem;
  border-radius: var(--radius-full);
  margin-bottom: 0.4rem;
}

.timer-digits {
  font-family: var(--font-mono);
  font-size: 3.4rem;
  font-weight: 800;
  letter-spacing: -0.04em;
  color: var(--text-main);
}

.timer-cycle-count {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-top: 0.3rem;
  font-weight: 500;
}

.timer-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  width: 100%;
  max-width: 380px;
  margin-bottom: 1.5rem;
}

/* Ambient Player */
.ambient-player {
  width: 100%;
  background: var(--bg-card-subtle);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 0.9rem;
}

.ambient-header {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 0.6rem;
}

.ambient-buttons {
  display: flex;
  gap: 0.5rem;
  justify-content: center;
  flex-wrap: wrap;
}

.ambient-btn {
  font-family: var(--font-main);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 0.4rem 0.8rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-muted);
  cursor: pointer;
  transition: var(--transition);
}

.ambient-btn:hover {
  color: var(--text-main);
  border-color: var(--primary);
}

.ambient-btn.active {
  background: var(--primary-light);
  color: var(--primary);
  border-color: var(--primary);
}

/* Task Card */
.task-form {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.task-form input {
  flex: 1;
  padding: 0.65rem 0.9rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-card-subtle);
  color: var(--text-main);
  font-family: var(--font-main);
  font-size: 0.88rem;
}

.task-form input:focus {
  outline: none;
  border-color: var(--primary);
}

.active-goal-box {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  background: var(--primary-light);
  border: 1px dashed var(--primary);
  border-radius: var(--radius-md);
  padding: 0.75rem 1rem;
  margin-bottom: 1.5rem;
}

.goal-checkbox {
  width: 18px;
  height: 18px;
  accent-color: var(--primary);
  cursor: pointer;
}

.goal-label {
  flex: 1;
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-main);
  cursor: pointer;
}

.goal-checkbox:checked + .goal-label {
  text-decoration: line-through;
  color: var(--text-muted);
}

.icon-btn-small {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 0.9rem;
  padding: 0.2rem;
}

.icon-btn-small:hover {
  color: var(--danger);
}

.study-tips-box {
  background: var(--bg-card-subtle);
  border-radius: var(--radius-md);
  padding: 1.1rem;
  border: 1px solid var(--border-color);
}

.study-tips-box h3 {
  font-size: 0.88rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
  color: var(--text-main);
}

.tips-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.tips-list li {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.45;
  position: relative;
  padding-left: 1rem;
}

.tips-list li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: bold;
}

/* ==========================================================================
   2. FLASHCARDS VIEW STYLES
   ========================================================================= */

.flashcards-container {
  display: flex;
  flex-direction: column;
  max-width: 680px;
  margin: 0 auto;
}

.flashcards-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.deck-selector-wrap {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.select-input, .text-input, .textarea-input {
  font-family: var(--font-main);
  font-size: 0.88rem;
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background-color: var(--bg-card);
  color: var(--text-main);
  outline: none;
  transition: var(--transition);
}

.select-input:focus, .text-input:focus, .textarea-input:focus {
  border-color: var(--primary);
}

.toolbar-actions {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
}

.deck-progress-bar-wrap {
  margin-bottom: 1.25rem;
}

.deck-progress-info {
  display: flex;
  justify-content: space-between;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

.progress-track {
  width: 100%;
  height: 8px;
  background-color: var(--border-color);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  border-radius: var(--radius-full);
  transition: width 0.3s ease;
}

/* 3D Flip Card */
.flashcard-scene {
  perspective: 1200px;
  width: 100%;
  height: 320px;
  margin-bottom: 1.5rem;
  cursor: pointer;
  outline: none;
}

.flashcard {
  position: relative;
  width: 100%;
  height: 100%;
  border-radius: var(--radius-lg);
  transform-style: preserve-3d;
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: var(--shadow-lg);
}

.flashcard.flipped {
  transform: rotateY(180deg);
}

.card-face {
  position: absolute;
  width: 100%;
  height: 100%;
  border-radius: var(--radius-lg);
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 1.75rem;
  border: 1px solid var(--border-color);
  background-color: var(--bg-card);
}

.card-front {
  background: linear-gradient(145deg, var(--bg-card), var(--bg-card-subtle));
}

.card-back {
  transform: rotateY(180deg);
  background: linear-gradient(145deg, var(--bg-card-subtle), var(--bg-card));
  border-color: rgba(79, 70, 229, 0.25);
}

.card-face-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.card-badge {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-full);
  background-color: var(--primary-light);
  color: var(--primary);
}

.card-badge-back {
  background-color: var(--success-light);
  color: var(--success);
}

.card-status-pill {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-full);
  background-color: var(--warning-light);
  color: var(--warning);
}

.card-status-pill.mastered {
  background-color: var(--success-light);
  color: var(--success);
}

.card-face-body {
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 1rem 0;
  min-height: 120px;
}

.card-prompt-text {
  font-size: 1.35rem;
  font-weight: 700;
  line-height: 1.45;
  color: var(--text-main);
}

.card-answer-text {
  font-size: 1.15rem;
  font-weight: 500;
  line-height: 1.55;
  color: var(--text-main);
}

.card-face-footer {
  text-align: center;
}

.hint-text {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-weight: 500;
}

.flashcard-controls {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.mastery-actions {
  display: flex;
  gap: 0.6rem;
}

.card-manage-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
}

.divider {
  color: var(--border-color);
}

/* ==========================================================================
   3. QUIZ VIEW STYLES
   ========================================================================== */

.quiz-container {
  max-width: 680px;
  margin: 0 auto;
}

.quiz-step-card {
  padding: 2.25rem;
}

.quiz-welcome {
  text-align: center;
  margin-bottom: 2rem;
}

.quiz-hero-icon {
  font-size: 3rem;
  margin-bottom: 0.75rem;
}

.quiz-title {
  font-size: 1.55rem;
  font-weight: 800;
  margin-bottom: 0.45rem;
}

.quiz-desc {
  font-size: 0.92rem;
  color: var(--text-muted);
  max-width: 480px;
  margin: 0 auto;
}

.quiz-options-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  margin-bottom: 2rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.form-label {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-main);
}

.quiz-action-bar {
  display: flex;
  justify-content: center;
}

/* Active Quiz */
.quiz-header-bar {
  margin-bottom: 1.5rem;
}

.quiz-progress-text {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.quiz-live-score {
  color: var(--primary);
  font-family: var(--font-mono);
}

.quiz-question-box {
  background: var(--bg-card-subtle);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  border: 1px solid var(--border-color);
}

.quiz-question-tag {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--primary);
  display: inline-block;
  margin-bottom: 0.4rem;
}

.quiz-question-text {
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.4;
}

.quiz-options-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.quiz-option-btn {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  width: 100%;
  padding: 1rem 1.25rem;
  background-color: var(--bg-card);
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-md);
  font-family: var(--font-main);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-main);
  text-align: left;
  cursor: pointer;
  transition: var(--transition);
}

.quiz-option-btn:hover:not(:disabled) {
  border-color: var(--primary);
  background-color: var(--primary-light);
  transform: translateY(-1px);
}

.option-badge {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-full);
  background-color: var(--bg-card-subtle);
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-muted);
  flex-shrink: 0;
}

.quiz-option-btn.selected-correct {
  background-color: var(--success-light);
  border-color: var(--success);
  color: var(--text-main);
}

.quiz-option-btn.selected-correct .option-badge {
  background-color: var(--success);
  color: #fff;
  border-color: var(--success);
}

.quiz-option-btn.selected-incorrect {
  background-color: var(--danger-light);
  border-color: var(--danger);
  color: var(--text-main);
}

.quiz-option-btn.selected-incorrect .option-badge {
  background-color: var(--danger);
  color: #fff;
  border-color: var(--danger);
}

.quiz-option-btn.should-have-selected {
  border-color: var(--success);
  border-style: dashed;
}

/* Feedback Box */
.quiz-feedback-box {
  background: var(--bg-card-subtle);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  border: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  animation: fadeIn 0.2s ease-out;
}

.feedback-indicator {
  font-size: 1.05rem;
  font-weight: 800;
}

.feedback-indicator.correct {
  color: var(--success);
}

.feedback-indicator.incorrect {
  color: var(--danger);
}

.feedback-explanation {
  font-size: 0.9rem;
  color: var(--text-main);
  line-height: 1.45;
}

/* Quiz Result View */
.quiz-result-hero {
  text-align: center;
  padding: 1rem 0 1.5rem 0;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 1.5rem;
}

.result-badge-icon {
  font-size: 3.5rem;
  margin-bottom: 0.5rem;
}

.result-title {
  font-size: 1.6rem;
  font-weight: 800;
}

.result-score-large {
  font-size: 3.5rem;
  font-weight: 900;
  color: var(--primary);
  font-family: var(--font-mono);
  letter-spacing: -0.04em;
  margin: 0.35rem 0;
}

.result-summary-text {
  font-size: 0.95rem;
  color: var(--text-muted);
}

.quiz-results-breakdown {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  max-height: 280px;
  overflow-y: auto;
  margin-bottom: 1.75rem;
  padding-right: 0.5rem;
}

.result-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-md);
  background: var(--bg-card-subtle);
  border-left: 4px solid var(--border-color);
}

.result-item.correct {
  border-left-color: var(--success);
}

.result-item.incorrect {
  border-left-color: var(--danger);
}

.result-item-info {
  flex: 1;
}

.result-item-q {
  font-weight: 700;
  font-size: 0.88rem;
  margin-bottom: 0.2rem;
}

.result-item-a {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.quiz-result-actions {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}

/* ==========================================================================
   Modals & Toast
   ========================================================================== */

.modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background-color: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 1rem;
  animation: fadeIn 0.2s ease-out;
}

.modal-dialog {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 500px;
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.modal-header h3 {
  font-size: 1.15rem;
  font-weight: 700;
}

.modal-close-btn {
  background: none;
  border: none;
  font-size: 1.15rem;
  color: var(--text-muted);
  cursor: pointer;
  padding: 0.2rem 0.5rem;
}

.modal-close-btn:hover {
  color: var(--text-main);
}

.modal-body {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
}

.modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

/* Toast */
.toast {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  background-color: var(--text-main);
  color: var(--bg-card);
  padding: 0.75rem 1.25rem;
  border-radius: var(--radius-md);
  font-size: 0.88rem;
  font-weight: 600;
  box-shadow: var(--shadow-lg);
  z-index: 2000;
  opacity: 0;
  transform: translateY(10px);
  pointer-events: none;
  transition: opacity 0.25s ease, transform 0.25s ease;
}

.toast.show {
  opacity: 1;
  transform: translateY(0);
}

/* ==========================================================================
   Responsive Adaptations
   ========================================================================== */

@media (max-width: 768px) {
  .app-header {
    flex-direction: column;
    align-items: stretch;
  }

  .nav-tabs {
    order: 3;
    width: 100%;
    justify-content: center;
  }

  .stats-bar {
    grid-template-columns: repeat(2, 1fr);
  }

  .pomodoro-grid {
    grid-template-columns: 1fr;
  }

  .quiz-options-grid {
    grid-template-columns: 1fr;
  }

  .flashcard-scene {
    height: 280px;
  }

  .flashcard-controls {
    flex-wrap: wrap;
    justify-content: center;
  }

  .mastery-actions {
    order: 3;
    width: 100%;
    justify-content: center;
  }
}