@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700;800&family=Inter:wght@400;500;600&display=swap');

/* ═══════════════════════════════════════
   DESIGN SYSTEM — TOKENS
   ═══════════════════════════════════════ */
:root {
  /* Primary palette - Algerian Green optimized for Dark Mode */
  --primary: #00C853;
  --primary-hover: #009624;
  --primary-glow: rgba(0, 200, 83, 0.45);
  --primary-soft: rgba(0, 200, 83, 0.15);

  /* Accent */
  --accent: #38D9A9;
  --accent-glow: rgba(56, 217, 169, 0.25);

  /* Surfaces */
  --bg-deep: #0f0d2e;
  --bg-mid: #1a1145;
  --bg-surface: rgba(255, 255, 255, 0.05);
  --card-bg: rgba(255, 255, 255, 0.06);
  --card-border: rgba(255, 255, 255, 0.1);
  --card-hover: rgba(255, 255, 255, 0.1);

  /* Text */
  --text: #F1F0FF;
  --text-secondary: rgba(241, 240, 255, 0.6);
  --text-muted: rgba(241, 240, 255, 0.4);

  /* Feedback */
  --correct: #38D9A9;
  --wrong: #FF6B6B;

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 8px 32px rgba(0, 0, 0, 0.3);
  --shadow-glow: 0 0 30px var(--primary-glow);

  /* Misc */
  --radius: 16px;
  --radius-sm: 10px;
  --radius-pill: 99px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ═══════════════════════════════════════
   RESET & BASE
   ═══════════════════════════════════════ */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  min-height: 100vh;
  font-family: 'Inter', 'Segoe UI', sans-serif;
  color: var(--text);
  background: var(--bg-deep);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  /* iOS Safe Area Support */
  padding-bottom: env(safe-area-inset-bottom);
}

body {
  background:
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(0, 200, 83, 0.15) 0%, transparent 60%),
    radial-gradient(ellipse 60% 40% at 80% 80%, rgba(56, 217, 169, 0.08) 0%, transparent 50%),
    radial-gradient(ellipse 50% 50% at 20% 60%, rgba(0, 200, 83, 0.06) 0%, transparent 50%),
    linear-gradient(180deg, var(--bg-deep) 0%, var(--bg-mid) 100%);
  background-attachment: fixed;
}

/* Floating orbs (decorative) */
body::before,
body::after {
  content: '';
  position: fixed;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.4;
  z-index: 0;
  pointer-events: none;
}

body::before {
  width: 500px;
  height: 500px;
  top: -100px;
  right: -100px;
  background: var(--primary-glow);
  animation: float 20s ease-in-out infinite;
}

body::after {
  width: 400px;
  height: 400px;
  bottom: -50px;
  left: -50px;
  background: var(--accent-glow);
  animation: float 25s ease-in-out infinite reverse;
}

@keyframes float {

  0%,
  100% {
    transform: translate(0, 0) scale(1);
  }

  33% {
    transform: translate(30px, -30px) scale(1.05);
  }

  66% {
    transform: translate(-20px, 20px) scale(0.95);
  }
}

/* ═══════════════════════════════════════
   TYPOGRAPHY
   ═══════════════════════════════════════ */
h1,
h2,
h3,
h4 {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  color: var(--text);
  line-height: 1.2;
}

h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 2rem;
  margin-bottom: 0.75rem;
}

h3 {
  font-size: 1.4rem;
  margin-bottom: 0.5rem;
}

h4 {
  font-size: 1.15rem;
}

h1 span,
h2 span {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

p,
li {
  line-height: 1.6;
}

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

a:hover {
  color: #9B7BFF;
}

/* ═══════════════════════════════════════
   LOGO
   ═══════════════════════════════════════ */
.logo {
  font-family: 'Outfit', sans-serif;
  font-size: 1.8rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-decoration: none;
  transition: opacity 0.2s;
}

.logo:hover {
  opacity: 0.85;
}

/* ═══════════════════════════════════════
   NAVIGATION — Frosted Glass
   ═══════════════════════════════════════ */
nav {
  position: sticky;
  top: 0;
  z-index: 100;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: calc(0.8rem + env(safe-area-inset-top)) 3vw 0.8rem 3vw;
  background: rgba(15, 13, 46, 0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}

nav .nav-links {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 0.5rem;
  align-items: center;
}

nav .nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-family: 'Outfit', sans-serif;
  font-size: 0.95rem;
  font-weight: 500;
  padding: 0.45rem 1rem;
  border-radius: var(--radius-pill);
  transition: all var(--transition);
  position: relative;
}

nav .nav-links a:hover {
  color: var(--text);
  background: var(--primary-soft);
}

nav .nav-links a.active {
  color: #fff;
  background: var(--primary);
  font-weight: 600;
  box-shadow: 0 2px 12px var(--primary-glow);
}

nav .nav-actions {
  display: flex;
  gap: 0.6rem;
  align-items: center;
}

/* Language Switcher Styling */
.lang-switcher {
  display: flex;
  align-items: center;
}

.lang-select {
  transition: all var(--transition) !important;
  background: rgba(255, 255, 255, 0.05) !important;
  border: 1px solid rgba(255, 255, 255, 0.1) !important;
  color: #fff !important;
  padding: 0.4rem 2rem 0.4rem 1rem !important;
  /* Extra right padding for arrow */
  border-radius: var(--radius-pill) !important;
  cursor: pointer !important;
  font-family: 'Outfit', sans-serif !important;
  font-size: 0.85rem !important;
  font-weight: 600 !important;
  appearance: none !important;
  -webkit-appearance: none !important;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='white' viewBox='0 0 16 16'%3E%3Cpath d='M7.247 11.14 2.451 5.658C1.885 5.013 2.345 4 3.204 4h9.592a1 1 0 0 1 .753 1.659l-4.796 5.48a1 1 0 0 1-1.506 0z'/%3E%3C/svg%3E") !important;
  background-repeat: no-repeat !important;
  background-position: right 0.8rem center !important;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1) !important;
}

.lang-select:hover {
  background-color: rgba(255, 255, 255, 0.1) !important;
  border-color: var(--primary) !important;
  box-shadow: 0 4px 15px rgba(0, 200, 83, 0.15) !important;
}

.lang-select option {
  background-color: #1a1145;
  color: #fff;
}

/* ═══════════════════════════════════════
   BUTTONS
   ═══════════════════════════════════════ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.65rem 1.4rem;
  font-family: 'Outfit', sans-serif;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
  text-align: center;
  line-height: 1.4;
}

.btn-primary,
.btn-purple {
  background: linear-gradient(135deg, var(--primary), #00E676);
  color: #fff;
  box-shadow: 0 4px 16px var(--primary-glow);
}

.btn-primary:hover,
.btn-purple:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px var(--primary-glow);
}

.btn-secondary,
.btn-outline {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--card-border);
  backdrop-filter: blur(8px);
}

.btn-secondary:hover,
.btn-outline:hover {
  background: var(--primary-soft);
  border-color: var(--primary);
  color: #fff;
}

.btn-yellow {
  background: linear-gradient(135deg, var(--accent), #5BEAD8);
  color: var(--bg-deep);
  font-weight: 700;
}

.btn-yellow:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px var(--accent-glow);
}

.btn-logout {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid rgba(255, 107, 107, 0.3);
}

.btn-logout:hover {
  background: rgba(255, 107, 107, 0.15);
  color: var(--wrong);
  border-color: var(--wrong);
}

/* Auth buttons in nav */
.btn.auth {
  background: linear-gradient(135deg, var(--primary), #9B7BFF);
  color: #fff;
  padding: 0.5rem 1.1rem;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
}

.btn.auth:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 16px var(--primary-glow);
}

/* ═══════════════════════════════════════
   CARDS — Glassmorphism
   ═══════════════════════════════════════ */
.card,
.main-card,
.quiz-start,
.question-card,
.mode-card,
.feedback-card,
.review-card {
  background: var(--card-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
  padding: 2rem 2.5rem;
  margin: 2rem auto;
  max-width: 600px;
  text-align: center;
  position: relative;
  z-index: 1;
  transition: all var(--transition);
}

.card:hover,
.main-card:hover {
  border-color: rgba(124, 92, 252, 0.2);
  box-shadow: var(--shadow-md), 0 0 40px rgba(124, 92, 252, 0.08);
}

.stat-card,
.progress-list,
.quality-btn,
.history-item,
.progression-card {
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  background: var(--card-bg);
  backdrop-filter: blur(8px);
  border: 1px solid var(--card-border);
}

/* ═══════════════════════════════════════
   SECTIONS & LAYOUT
   ═══════════════════════════════════════ */
section,
.main {
  margin-top: 2.5rem;
  margin-bottom: 2.5rem;
  position: relative;
  z-index: 1;
}

.main {
  flex: 1;
  padding: 1rem 2rem 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
}

main {
  position: relative;
  z-index: 1;
}

.emoji,
.icon {
  font-size: 1.6rem;
  margin-bottom: 0.3rem;
}

/* ═══════════════════════════════════════
   FOOTER
   ═══════════════════════════════════════ */
footer {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
  margin: 3rem 0 1.5rem 0;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  position: relative;
  z-index: 1;
}

/* ═══════════════════════════════════════
   PROGRESS BAR
   ═══════════════════════════════════════ */
.progress-container {
  width: 100%;
  max-width: 600px;
  margin: 1.5rem auto 2rem auto;
  display: flex;
  align-items: center;
  gap: 1rem;
  justify-content: center;
}

.progress-bar-container {
  width: 100%;
  height: 8px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 0.5em;
}

.progress-bar {
  width: 100%;
  height: 16px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 8px;
  overflow: hidden;
  position: relative;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 8px;
  transition: width 0.5s ease;
  width: 0%;
  position: absolute;
  left: 0;
  top: 0;
}

.progress-text {
  font-weight: 600;
  color: var(--text-secondary);
  min-width: 60px;
  text-align: right;
  font-family: 'Outfit', sans-serif;
}

.progress-bar-container .progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--primary), var(--accent)) !important;
  transition: width 0.3s;
  width: 0%;
  border-radius: 4px;
}

/* ═══════════════════════════════════════
   REVIEW / DISCOVERY HEADERS
   ═══════════════════════════════════════ */
.discovery-header,
.review-header,
.quiz-header {
  text-align: center;
  margin-bottom: 1.5rem;
  position: relative;
  z-index: 1;
}

.discovery-header h2,
.review-header h2,
.quiz-header h2 {
  font-size: 1.75rem;
  margin-bottom: 0.5rem;
}

.discovery-header p,
.review-header p,
.quiz-header p {
  color: var(--text-secondary);
  font-size: 1.05rem;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 1.15rem;
  font-weight: 500;
  margin-bottom: 0.3em;
}

.explication {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 1.2em;
}

/* ═══════════════════════════════════════
   QUIZ MODE
   ═══════════════════════════════════════ */
.quiz-start {
  text-align: center;
  max-width: 500px;
}

.quiz-start h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

.question-count-selector {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}

.question-card {
  max-width: 500px;
  width: 100%;
}

.question-text {
  font-family: 'Outfit', sans-serif;
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 2rem;
  text-align: center;
}

.options-container {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.option-btn {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  padding: 1rem;
  font-size: 1rem;
  color: var(--text);
  cursor: pointer;
  transition: all var(--transition);
  text-align: left;
  backdrop-filter: blur(4px);
}

.option-btn:hover:not(:disabled) {
  background: var(--primary-soft);
  border-color: var(--primary);
  transform: translateX(4px);
}

.option-btn.correct {
  background: rgba(56, 217, 169, 0.2);
  color: var(--accent);
  border-color: var(--accent);
}

.option-btn.incorrect {
  background: rgba(255, 107, 107, 0.2);
  color: var(--wrong);
  border-color: var(--wrong);
}

.option-btn:disabled {
  cursor: not-allowed;
  opacity: 0.7;
}

/* ═══════════════════════════════════════
   REVIEW MODE — FLASHCARD
   ═══════════════════════════════════════ */
.review-card {
  max-width: 500px;
  width: 100%;
  text-align: center;
}

.card-front,
.card-back {
  cursor: pointer;
  padding: 2rem;
  border-radius: var(--radius-sm);
  transition: background var(--transition);
}

.card-front:hover,
.card-back:hover {
  background: rgba(255, 255, 255, 0.03);
}

.card-text {
  font-family: 'Outfit', sans-serif;
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--text);
}

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

.card-original {
  color: var(--primary);
  font-size: 1.1rem;
  font-weight: 500;
}

.quality-buttons {
  display: flex;
  gap: 0.6rem;
  justify-content: center;
  margin-top: 2rem;
  flex-wrap: wrap;
}

.quality-btn {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-pill);
  padding: 0.6rem 1.2rem;
  font-size: 0.9rem;
  font-family: 'Outfit', sans-serif;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  transition: all var(--transition);
  min-width: 80px;
}

.audio-btn-small {
  background: var(--primary-soft);
  border: 1px solid var(--primary);
  color: #fff;
  border-radius: 50%;
  width: 36px;
  height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  margin-left: 0.5rem;
  font-size: 1.1rem;
  transition: all var(--transition);
  vertical-align: middle;
}

.audio-btn-small:hover {
  background: var(--primary);
  transform: scale(1.1);
  box-shadow: 0 0 12px var(--primary-glow);
}

.quality-btn:hover {
  transform: translateY(-2px);
}

/* Colored quality buttons */
.quality-hard {
  border-color: #ff4d4f;
  background: rgba(255, 77, 79, 0.1);
  color: #ff6b6d;
}

.quality-hard:hover {
  background: #ff4d4f;
  color: #fff;
  box-shadow: 0 4px 16px rgba(255, 77, 79, 0.3);
}

.quality-medium {
  border-color: #faad14;
  background: rgba(250, 173, 20, 0.1);
  color: #ffc53d;
}

.quality-medium:hover {
  background: #faad14;
  color: #fff;
  box-shadow: 0 4px 16px rgba(250, 173, 20, 0.3);
}

.quality-easy {
  border-color: #52c41a;
  background: rgba(82, 196, 26, 0.1);
  color: #73d13d;
}

.quality-easy:hover {
  background: #52c41a;
  color: #fff;
  box-shadow: 0 4px 16px rgba(82, 196, 26, 0.3);
}

/* ═══════════════════════════════════════
   FLASHCARD 3D FLIP
   ═══════════════════════════════════════ */
.flashcard-container {
  perspective: 1200px;
  width: 100%;
  max-width: 420px;
  margin: 0 auto;
  height: 300px;
  animation: cardAppear 0.5s ease-out;
}

.flashcard {
  position: relative;
  width: 100%;
  height: 100%;
  transform-style: preserve-3d;
  transition: transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
}

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

.card-face {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  border-radius: var(--radius);
  background: var(--card-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--card-border);
  box-shadow: var(--shadow-md);
}

.card-face.front {
  background: linear-gradient(135deg, rgba(124, 92, 252, 0.08) 0%, rgba(56, 217, 169, 0.05) 100%);
  border-color: rgba(124, 92, 252, 0.15);
}

.card-face.back {
  background: linear-gradient(135deg, rgba(56, 217, 169, 0.08) 0%, rgba(124, 92, 252, 0.05) 100%);
  border-color: rgba(56, 217, 169, 0.15);
  transform: rotateY(180deg);
}

.card-comment {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-top: 0.8rem;
  font-style: italic;
  text-align: center;
  max-width: 90%;
  line-height: 1.4;
}

.card-example {
  font-size: 0.98rem;
  color: var(--accent);
  margin-top: 0.5rem;
  text-align: center;
  max-width: 90%;
  line-height: 1.4;
  font-weight: 500;
  font-style: italic;
}

.card-extra {
  margin-top: 0.75rem;
  max-width: 90%;
  text-align: center;
}

.flip-indicator {
  position: absolute;
  bottom: 1rem;
  right: 1rem;
  background: rgba(124, 92, 252, 0.1);
  border-radius: 50%;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: var(--primary);
  backdrop-filter: blur(4px);
}

@keyframes cardAppear {
  from {
    opacity: 0;
    transform: scale(0.9) translateY(20px);
  }

  to {
    opacity: 1;
    transform: scale(1) translateY(0);
  }
}

/* ═══════════════════════════════════════
   FEEDBACK & RESULTS
   ═══════════════════════════════════════ */
.feedback-card,
.quiz-results,
.review-results,
.no-cards-message {
  background: var(--card-bg);
  backdrop-filter: blur(12px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 2rem;
  box-shadow: var(--shadow-md);
  max-width: 500px;
  width: 100%;
  text-align: center;
  margin: 2rem auto;
}

.feedback-card h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

.next-interval {
  color: var(--text-secondary);
  font-size: 1rem;
}

.score-display,
.stats-display {
  margin: 1.5rem 0;
}

.score-display p,
.stats-display p {
  font-size: 1.1rem;
  margin: 0.5rem 0;
}

.result-message {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin: 1.5rem 0;
  line-height: 1.5;
}

.action-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 2rem;
}

/* ═══════════════════════════════════════
   LOADING
   ═══════════════════════════════════════ */
.review-loading {
  text-align: center;
  background: var(--card-bg);
  backdrop-filter: blur(8px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 2rem;
  box-shadow: var(--shadow-md);
  max-width: 500px;
  width: 100%;
}

.loading-spinner {
  width: 40px;
  height: 40px;
  border: 3px solid rgba(255, 255, 255, 0.1);
  border-top: 3px solid var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin: 1rem auto;
}

@keyframes spin {
  0% {
    transform: rotate(0deg);
  }

  100% {
    transform: rotate(360deg);
  }
}

/* ═══════════════════════════════════════
   LOGIN / SIGNUP FORMS
   ═══════════════════════════════════════ */
.signup-main {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 2rem;
  min-height: 60vh;
  position: relative;
  z-index: 1;
}

.signup-form {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  width: 100%;
  max-width: 380px;
}

.signup-form label {
  font-family: 'Outfit', sans-serif;
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.signup-form input {
  width: 100%;
  padding: 0.85rem 1rem;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  font-size: 1rem;
  color: var(--text);
  font-family: 'Inter', sans-serif;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.signup-form input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-soft);
}

.signup-form input::placeholder {
  color: var(--text-muted);
}

.signup-form .btn.auth {
  background: linear-gradient(135deg, var(--primary), #9B7BFF);
  color: #fff;
  padding: 1rem;
  font-size: 1.05rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  font-family: 'Outfit', sans-serif;
}

.signup-form .btn.auth:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px var(--primary-glow);
}

/* ═══════════════════════════════════════
   PROGRESS PAGE
   ═══════════════════════════════════════ */
.welcome-text {
  font-family: 'Outfit', sans-serif;
  font-size: 1.8rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  text-align: center;
}

.username-text {
  font-family: 'Outfit', sans-serif;
  font-size: 2.5rem;
  font-weight: 800;
  text-align: center;
  margin-bottom: 2rem;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Stats Grid */
.stats-overview {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.2rem;
  margin: 2rem 0;
  width: 100%;
  max-width: 800px;
}

.stat-card {
  background: var(--card-bg);
  backdrop-filter: blur(8px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  text-align: center;
  transition: all var(--transition);
}

.stat-card:hover {
  transform: translateY(-3px);
  border-color: rgba(124, 92, 252, 0.2);
  box-shadow: var(--shadow-glow);
}

.stat-card h3 {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
  font-weight: 500;
}

.stat-number {
  font-family: 'Outfit', sans-serif;
  font-size: 2.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 0.25rem;
}

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

/* Progress list */
.progress-list {
  margin-top: 2rem;
  width: 100%;
  max-width: 480px;
}

.progress-list ul {
  list-style: none;
  padding: 0;
}

.progress-list li {
  background: var(--card-bg);
  padding: 1rem;
  border-radius: var(--radius-sm);
  margin-bottom: 0.75rem;
  border: 1px solid var(--card-border);
}

.score-summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.score-label {
  font-weight: 600;
}

.progress-percent {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* Stats section */
.stats-section {
  width: 100%;
  max-width: 800px;
  margin-bottom: 2rem;
}

.stats-section h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  text-align: center;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--card-border);
}

/* Revision history */
.revision-history {
  width: 100%;
  max-width: 800px;
  margin-top: 2rem;
}

.revision-history h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  text-align: center;
}

.history-list {
  background: var(--card-bg);
  backdrop-filter: blur(8px);
  border-radius: var(--radius);
  padding: 0.5rem;
  border: 1px solid var(--card-border);
}

.history-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  transition: background var(--transition);
}

.history-item:last-child {
  border-bottom: none;
}

.history-item:hover {
  background: rgba(255, 255, 255, 0.03);
}

.history-word {
  flex: 1;
  font-size: 1rem;
}

.history-details {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.25rem;
}

.history-date {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.history-quality {
  font-size: 0.9rem;
  font-weight: 600;
}

/* ═══════════════════════════════════════
   LEARNING MODES
   ═══════════════════════════════════════ */
.learning-modes {
  width: 100%;
  max-width: 800px;
  margin-bottom: 2rem;
}

.mode-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
  margin-top: 1rem;
}

.mode-card {
  transition: all var(--transition);
}

.mode-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow);
  border-color: rgba(124, 92, 252, 0.2);
}

.mode-card h4 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.mode-card p {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.5;
}

/* ═══════════════════════════════════════
   CTA / FEATURES
   ═══════════════════════════════════════ */
.cta-row {
  display: flex;
  gap: 1rem;
  justify-content: center;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.features-row {
  display: flex;
  justify-content: center;
  gap: 2.5rem;
  flex-wrap: wrap;
  margin-bottom: 1.5rem;
}

.feature {
  text-align: center;
  font-size: 1.05rem;
  color: var(--text-secondary);
}

/* ═══════════════════════════════════════
   LEXIQUE
   ═══════════════════════════════════════ */
.lexique-theme {
  margin-bottom: 2em;
  background: var(--card-bg);
  backdrop-filter: blur(8px);
  border-radius: var(--radius);
  padding: 1.5em;
  border: 1px solid var(--card-border);
  overflow: hidden;
}

.lexique-theme h3 {
  color: var(--primary);
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 1em;
  padding-bottom: 0.5em;
  border-bottom: 1px solid rgba(124, 92, 252, 0.2);
  font-family: 'Outfit', sans-serif;
}

.lexique-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75em;
}

.lexique-list li {
  background: rgba(255, 255, 255, 0.03);
  padding: 1em 1.2em;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(255, 255, 255, 0.05);
  transition: all var(--transition);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.75em;
  min-width: 0;
  overflow: hidden;
}

.lexique-list li:hover {
  background: var(--primary-soft);
  border-color: rgba(124, 92, 252, 0.2);
  transform: translateY(-2px);
}

.lexique-list .fr {
  font-weight: 600;
  color: var(--text);
  font-size: 1rem;
}

.lexique-list .kab {
  color: var(--primary);
  font-weight: 500;
  font-size: 0.95rem;
  text-align: right;
  overflow-wrap: break-word;
  word-break: break-word;
}

.lexique-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1em;
  margin-bottom: 1.5rem;
}

.lexique-controls label {
  font-weight: 600;
  color: var(--text);
}

.lexique-controls select {
  padding: 0.6em 1em;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  background: var(--bg-mid);
  color: var(--text);
  font-size: 1rem;
  cursor: pointer;
  transition: all var(--transition);
}

.lexique-controls select:hover,
.lexique-controls select:focus {
  border-color: var(--primary);
  outline: none;
  box-shadow: 0 0 0 3px var(--primary-soft);
}

/* ═══════════════════════════════════════
   OLD CARD / CHOICES COMPAT
   ═══════════════════════════════════════ */
.card {
  width: 320px;
  text-align: center;
  margin-bottom: 1rem;
}

.face {
  font-size: 1.6rem;
  font-weight: 600;
}

#back {
  display: none;
  margin-top: 1rem;
  color: var(--primary);
}

#back.visible {
  display: block;
}

#choices {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  width: 320px;
  margin-bottom: 1.5rem;
}

#choices button {
  background: var(--card-bg);
  color: var(--text);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  padding: 0.7rem 1rem;
  font-size: 1rem;
  cursor: pointer;
  transition: all var(--transition);
}

#choices button:hover {
  border-color: var(--primary);
  background: var(--primary-soft);
}

#choices button.correct {
  background: rgba(56, 217, 169, 0.2);
  color: var(--accent);
  border-color: var(--accent);
}

#choices button.wrong {
  background: rgba(255, 107, 107, 0.2);
  color: var(--wrong);
  border-color: var(--wrong);
}

.controls {
  display: flex;
  gap: 1rem;
  justify-content: center;
}

.controls button {
  background: linear-gradient(135deg, var(--primary), #9B7BFF);
  color: white;
  border: none;
  padding: 0.6rem 1.2rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition);
}

.controls button:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 16px var(--primary-glow);
}

.controls button:active {
  transform: translateY(1px);
}

.auth-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  align-items: center;
}

/* ═══════════════════════════════════════
   LEGACY HIDE
   ═══════════════════════════════════════ */
.header,
.header-auth,
.mobile-nav,
.sidebar,
.layout {
  display: none !important;
}

/* ═══════════════════════════════════════
   SCROLLBAR
   ═══════════════════════════════════════ */
::-webkit-scrollbar {
  width: 8px;
  background: var(--bg-deep);
}

::-webkit-scrollbar-thumb {
  background: rgba(124, 92, 252, 0.3);
  border-radius: 8px;
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(124, 92, 252, 0.5);
}

/* ═══════════════════════════════════════
   MOBILE — max-width: 600px
   ═══════════════════════════════════════ */
@media (max-width: 600px) {
  nav {
    display: none !important;
  }

  nav .nav-links {
    display: none;
  }

  .nav-actions {
    display: none;
  }

  h1 {
    font-size: 1.8rem;
  }

  h2 {
    font-size: 1.4rem;
  }

  .card,
  .main-card,
  .quiz-start,
  .question-card,
  .mode-card,
  .feedback-card,
  .review-card,
  .review-results {
    padding: 1.2rem 1rem;
    margin: 1rem auto;
    border-radius: var(--radius);
    max-width: 95vw;
  }

  .btn {
    font-size: 0.9rem;
    padding: 0.6em 1em;
  }

  body {
    padding-bottom: 80px;
  }

  /* Mobile menu button */
  .mobile-menu-btn {
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 1001;
    background: linear-gradient(135deg, var(--primary), #9B7BFF);
    color: white;
    border: none;
    border-radius: 50%;
    width: 56px;
    height: 56px;
    padding: 0;
    font-size: 1.4rem;
    font-weight: 600;
    cursor: pointer;
    box-shadow: 0 4px 20px var(--primary-glow);
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: auto;
    user-select: none;
    -webkit-tap-highlight-color: rgba(124, 92, 252, 0.3);
    transition: all var(--transition);
  }

  .mobile-menu-btn:hover {
    transform: scale(1.05);
  }

  .mobile-menu-btn:active {
    transform: scale(0.95);
  }

  /* Mobile menu panel */
  .mobile-menu {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(15, 13, 46, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
    z-index: 1000;
    transform: translateY(-100%);
    transition: transform 0.3s ease;
    padding: 80px 24px 24px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    border-bottom: 1px solid var(--card-border);
  }

  .mobile-menu.open {
    transform: translateY(0);
    display: flex !important;
    visibility: visible !important;
    opacity: 1 !important;
  }

  .mobile-menu a {
    color: var(--text);
    text-decoration: none;
    font-family: 'Outfit', sans-serif;
    font-size: 1.1rem;
    font-weight: 600;
    padding: 14px 20px;
    border-radius: var(--radius-sm);
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid transparent;
    transition: all var(--transition);
    text-align: center;
  }

  .mobile-menu a:hover,
  .mobile-menu a.active {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
  }

  .mobile-menu-bg {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
    display: none;
  }

  .mobile-menu-bg.open {
    display: block;
  }

  /* Hide old elements */
  .burger-menu-btn,
  .burger-menu,
  .mobile-tabbar {
    display: none !important;
  }

  .question-card {
    margin: 2rem auto 1.5rem;
    max-width: 95vw;
    padding: 1.2rem 0.5rem;
  }

  .option-btn {
    width: 100%;
    max-width: 95vw;
    font-size: 1rem;
    padding: 1rem 0.8rem;
  }

  .review-card {
    margin: 1rem auto;
    max-width: 95vw;
    min-height: 280px;
  }

  .card-front,
  .card-back {
    padding: 1rem 0.5rem;
    font-size: 1.1rem;
  }

  .quality-buttons {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 0.5rem;
    padding-bottom: 80px !important;
  }

  .quality-btn {
    flex: 1;
    min-width: 70px;
    font-size: 0.85rem;
    padding: 0.6rem 0.4rem;
  }

  .flashcard-container {
    max-width: 95vw;
    height: 260px;
  }

  .card-text {
    font-size: 1.5rem;
  }

  .stats-overview {
    grid-template-columns: 1fr;
    gap: 0.8rem;
  }

  .stat-card {
    padding: 1rem;
  }

  .features-row,
  .cta-row {
    flex-direction: column;
    gap: 0.8rem;
    align-items: center;
  }

  .lexique-list {
    grid-template-columns: 1fr;
  }

  .lexique-list li {
    flex-direction: column;
    text-align: center;
    gap: 0.4em;
  }

  .lexique-list .kab {
    max-width: 100%;
    text-align: center;
  }

  .lexique-controls {
    flex-direction: column;
    text-align: center;
  }

  .feedback-card {
    border-radius: var(--radius);
    margin: 1em auto;
    padding: 1.5em 1em;
    width: 95vw;
    max-width: 420px;
  }
}

@media (max-width: 400px) {
  h1 {
    font-size: 1.5rem;
  }

  h2 {
    font-size: 1.2rem;
  }

  .card,
  .main-card,
  .quiz-start,
  .question-card {
    padding: 0.8rem 0.4rem;
    max-width: 100vw;
  }
}

/* Desktop only — hide mobile elements */
@media (min-width: 601px) {

  .mobile-menu-btn,
  .mobile-menu,
  .mobile-menu-bg {
    display: none !important;
    visibility: hidden !important;
    opacity: 0 !important;
    pointer-events: none !important;
    height: 0 !important;
    width: 0 !important;
    position: absolute !important;
    z-index: -1 !important;
    overflow: hidden !important;
  }
}

/* Logo img fallback hide */
.logo img[alt][src=''],
.logo img:not([src]) {
  display: none !important;
}

/* ═══════════════════════════════════════
   PROGRESS PAGE REDESIGN
   ═══════════════════════════════════════ */

/* Header & Hero */
.progress-hero {
  text-align: center;
  margin-bottom: 2rem;
  padding: 2rem;
  background: var(--card-bg);
  backdrop-filter: blur(12px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  position: relative;
  overflow: hidden;
}

.progress-hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(124, 92, 252, 0.1) 0%, transparent 60%);
  animation: rotate 20s linear infinite;
  z-index: 0;
}

@keyframes rotate {
  from {
    transform: rotate(0deg);
  }

  to {
    transform: rotate(360deg);
  }
}

.hero-content {
  position: relative;
  z-index: 1;
}

.level-badge {
  display: inline-block;
  background: linear-gradient(135deg, #FFD700, #FFA500);
  color: #1a1a2e;
  padding: 0.5rem 1.5rem;
  border-radius: 50px;
  font-weight: 800;
  font-size: 1.2rem;
  box-shadow: 0 4px 15px rgba(255, 215, 0, 0.3);
  margin-bottom: 1rem;
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* Progress Ring Container */
.main-dashboard {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}

.progress-ring-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--card-border);
  position: relative;
}

.progress-ring {
  width: 180px;
  height: 180px;
}

.progress-ring__circle {
  transition: stroke-dashoffset 1s ease-in-out;
  transform: rotate(-90deg);
  transform-origin: 50% 50%;
}

.progress-text-centered {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
}

.progress-percentage {
  font-size: 2.5rem;
  font-weight: 800;
  color: white;
  display: block;
}

.progress-label {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Stats Grid Redesigned */
.stats-grid-small {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.mini-stat-card {
  background: rgba(255, 255, 255, 0.03);
  padding: 1.5rem;
  border-radius: var(--radius);
  border: 1px solid var(--card-border);
  display: flex;
  align-items: center;
  gap: 1.5rem;
  transition: transform 0.2s;
}

.mini-stat-card:hover {
  transform: translateY(-2px);
  background: rgba(255, 255, 255, 0.05);
}

.mini-stat-icon {
  font-size: 2rem;
}

.mini-stat-info h4 {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 0.2rem;
}

.mini-stat-value {
  font-size: 1.8rem;
  font-weight: 700;
  color: white;
}

/* CTA Button */
.action-area {
  margin-top: 2rem;
  text-align: center;
}

.btn-large-cta {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: white;
  padding: 1rem 3rem;
  font-size: 1.2rem;
  border-radius: 50px;
  border: none;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 4px 20px var(--primary-glow);
  transition: all 0.3s ease;
  text-decoration: none;
  display: inline-block;
}

.btn-large-cta:hover {
  transform: scale(1.05);
  box-shadow: 0 8px 30px rgba(0, 200, 83, 0.6);
}

/* Mobile Adjustments */
@media (max-width: 768px) {
  .main-dashboard {
    grid-template-columns: 1fr;
  }

  .btn {
    padding: 0.8rem 1.6rem;
    font-size: 1rem;
    min-height: 44px;
    /* Apple recommendation */
  }

  .nav-links a {
    padding: 0.6rem 1.2rem;
  }
}