/* VerbalMaster - Modern Responsive CSS Design System */
@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800&family=Plus+Jakarta+Sans:wght@400;500;600;700&display=swap');

:root {
  /* Color Palette - Modern Dark Theme Default */
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-card: rgba(30, 41, 59, 0.7);
  --bg-card-hover: rgba(51, 65, 85, 0.8);
  --bg-input: #0f172a;
  
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --accent-primary: #6366f1; /* Indigo */
  --accent-primary-hover: #4f46e5;
  --accent-secondary: #06b6d4; /* Cyan */
  --accent-success: #10b981;
  --accent-warning: #f59e0b;
  --accent-danger: #ef4444;

  --border-color: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(99, 102, 241, 0.3);

  --font-heading: 'Outfit', sans-serif;
  --font-body: 'Plus Jakarta Sans', sans-serif;
  
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.3);
  --shadow-glow: 0 0 25px rgba(99, 102, 241, 0.25);

  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Light Theme Variables */
[data-theme="light"] {
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-card: #ffffff;
  --bg-card-hover: #f1f5f9;
  --bg-input: #f1f5f9;

  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #64748b;

  --border-color: rgba(0, 0, 0, 0.08);
  --border-glow: rgba(99, 102, 241, 0.25);
  --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.05);
}

/* Reset & Global */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: var(--font-body);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  overflow-x: hidden;
  line-height: 1.6;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-primary);
}

a {
  color: var(--accent-primary);
  text-decoration: none;
}

/* App Container Layout */
#app-container {
  display: flex;
  width: 100vw;
  min-height: 100vh;
}

/* Sidebar Navigation */
.sidebar {
  width: 280px;
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  padding: 1.5rem 1rem;
  position: fixed;
  height: 100vh;
  top: 0;
  left: 0;
  z-index: 100;
  transition: var(--transition-normal);
  backdrop-filter: blur(12px);
}

.brand-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.5rem 0.75rem 1.5rem 0.75rem;
  border-bottom: 1px solid var(--border-color);
}

.brand-logo {
  width: 42px;
  height: 42px;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  color: white;
  box-shadow: var(--shadow-glow);
}

.brand-title {
  font-size: 1.35rem;
  font-weight: 800;
  background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-section-label {
  font-size: 0.725rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.2px;
  color: var(--text-muted);
  margin: 1.5rem 0.75rem 0.5rem 0.75rem;
}

.nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.nav-item button {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 0.85rem;
  padding: 0.8rem 1rem;
  background: transparent;
  border: none;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-fast);
  text-align: left;
}

.nav-item button:hover {
  background: var(--bg-card-hover);
  color: var(--text-primary);
}

.nav-item.active button {
  background: linear-gradient(90deg, rgba(99, 102, 241, 0.2), rgba(6, 182, 212, 0.1));
  color: var(--accent-primary);
  border-left: 3px solid var(--accent-primary);
}

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

/* Main Content Area */
.main-wrapper {
  margin-left: 280px;
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background: var(--bg-primary);
}

/* Top Navigation Bar */
.top-bar {
  height: 70px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 2rem;
  position: sticky;
  top: 0;
  z-index: 90;
  backdrop-filter: blur(10px);
}

.exam-switcher {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.exam-chip {
  padding: 0.45rem 1rem;
  border-radius: var(--radius-full);
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-fast);
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.exam-chip:hover {
  border-color: var(--accent-primary);
  color: var(--text-primary);
}

.exam-chip.active {
  background: var(--accent-primary);
  color: white;
  border-color: var(--accent-primary);
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.user-controls {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.icon-btn {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition-fast);
}

.icon-btn:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-primary);
}

/* Content Views Container */
.content-area {
  padding: 2rem;
  max-width: 1400px;
  width: 100%;
  margin: 0 auto;
}

.view-panel {
  display: none;
  animation: fadeIn 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}

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

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Glass Card */
.glass-card {
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-md);
  transition: var(--transition-normal);
}

.glass-card:hover {
  border-color: rgba(255, 255, 255, 0.15);
}

/* Dashboard Hero */
.hero-banner {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.15), rgba(6, 182, 212, 0.15));
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  padding: 2.25rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  position: relative;
  overflow: hidden;
}

.hero-content h2 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.hero-content p {
  color: var(--text-secondary);
  font-size: 1.05rem;
  max-width: 650px;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.25rem;
  margin-bottom: 2rem;
}

.stat-card {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.stat-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: rgba(99, 102, 241, 0.15);
  color: var(--accent-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}

.stat-info .stat-value {
  font-size: 1.6rem;
  font-weight: 800;
  font-family: var(--font-heading);
}

.stat-info .stat-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* Buttons */
.btn {
  padding: 0.75rem 1.4rem;
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: var(--transition-fast);
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-primary-hover));
  color: white;
  box-shadow: 0 4px 14px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
}

.btn-secondary {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-primary);
}

.btn-success {
  background: var(--accent-success);
  color: white;
}

/* Section Header */
.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
}

.section-title {
  font-size: 1.5rem;
}

/* Reading Comprehension Studio Layout */
.rc-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  align-items: start;
}

@media (max-width: 1024px) {
  .rc-container {
    grid-template-columns: 1fr;
  }
}

.rc-passage-box {
  max-height: 75vh;
  overflow-y: auto;
  padding-right: 1rem;
}

.rc-passage-text {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--text-primary);
}

.rc-passage-text p {
  margin-bottom: 1.2rem;
}

.question-card {
  margin-bottom: 1.5rem;
}

.option-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-top: 1rem;
}

.option-btn {
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  text-align: left;
  cursor: pointer;
  font-size: 0.95rem;
  transition: var(--transition-fast);
}

.option-btn:hover {
  border-color: var(--accent-primary);
  background: var(--bg-card-hover);
}

.option-btn.selected {
  border-color: var(--accent-primary);
  background: rgba(99, 102, 241, 0.15);
}

.option-btn.correct {
  border-color: var(--accent-success);
  background: rgba(16, 185, 129, 0.15);
  color: #34d399;
}

.option-btn.wrong {
  border-color: var(--accent-danger);
  background: rgba(239, 68, 68, 0.15);
  color: #f87171;
}

.explanation-box {
  margin-top: 1rem;
  padding: 1rem 1.25rem;
  background: rgba(99, 102, 241, 0.1);
  border-left: 4px solid var(--accent-primary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  font-size: 0.9rem;
  line-height: 1.6;
}

/* Flashcard Styles */
.flashcard-wrapper {
  perspective: 1000px;
  max-width: 550px;
  margin: 2rem auto;
}

.flashcard {
  width: 100%;
  min-height: 320px;
  background: var(--bg-card);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  cursor: pointer;
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  transform-style: preserve-3d;
  box-shadow: var(--shadow-md);
  position: relative;
}

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

.flashcard-front, .flashcard-back {
  backface-visibility: hidden;
  width: 100%;
}

.flashcard-back {
  transform: rotateY(180deg);
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  padding: 2rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.word-title {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--accent-primary);
  margin-bottom: 0.25rem;
}

.phonetic {
  color: var(--text-muted);
  font-size: 1rem;
  margin-bottom: 1rem;
}

.flashcard-controls {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-top: 1.5rem;
}

/* Mock Test Palette */
.mock-grid {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 1.5rem;
}

@media (max-width: 900px) {
  .mock-grid {
    grid-template-columns: 1fr;
  }
}

.question-palette {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0.5rem;
  margin-top: 1rem;
}

.palette-item {
  height: 40px;
  border-radius: var(--radius-sm);
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  cursor: pointer;
}

.palette-item.answered {
  background: var(--accent-success);
  color: white;
  border-color: var(--accent-success);
}

.palette-item.active {
  border-color: var(--accent-primary);
  box-shadow: 0 0 10px var(--accent-primary);
}

/* Timer Badge */
.timer-badge {
  background: rgba(245, 158, 11, 0.15);
  border: 1px solid var(--accent-warning);
  color: var(--accent-warning);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-full);
  font-weight: 700;
  font-family: monospace;
  font-size: 1.1rem;
}

/* Responsive Sidebar Toggle for Mobile */
@media (max-width: 768px) {
  .sidebar {
    transform: translateX(-100%);
  }
  .sidebar.mobile-open {
    transform: translateX(0);
  }
  .main-wrapper {
    margin-left: 0;
  }
}