/* =============================================
   FLASH CARDS – Professional Design System
   Dark editorial aesthetic with gold accents
   ============================================= */

/* --- FONTS --- */
/* Playfair Display (headings) + DM Sans (body) via Google Fonts */

/* --- CSS VARIABLES --- */
:root {
  --bg:        #0d0d0f;
  --bg-card:   #141418;
  --bg-raised: #1c1c22;
  --border:    rgba(255,255,255,0.08);
  --border-hover: rgba(255,255,255,0.18);

  --gold:      #c9a84c;
  --gold-light:#e8c97a;
  --gold-dim:  rgba(201,168,76,0.15);

  --text-primary:   #f0ede6;
  --text-secondary: #9a9792;
  --text-muted:     #5a5855;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;

  --shadow-card: 0 4px 24px rgba(0,0,0,0.4);
  --shadow-glow: 0 0 40px rgba(201,168,76,0.12);

  --font-display: 'Playfair Display', Georgia, serif;
  --font-body:    'DM Sans', system-ui, sans-serif;

  --max-w: 1100px;
  --header-h: 68px;
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.7;
  min-height: 100vh;
  overflow-x: hidden;
}

/* --- BACKGROUND GRID --- */
.bg-grid {
  position: fixed;
  inset: 0;
  z-index: 0;
  background-image:
    linear-gradient(rgba(201,168,76,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(201,168,76,0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
}

body > *:not(.bg-grid) { position: relative; z-index: 1; }

/* --- TYPOGRAPHY --- */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  line-height: 1.15;
  color: var(--text-primary);
}

a { color: inherit; text-decoration: none; }

/* --- HEADER --- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(13,13,15,0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 2rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  transition: color 0.2s;
}
.logo:hover { color: var(--gold); }
.logo-icon { color: var(--gold); font-size: 1.4rem; }

.main-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.2s;
  letter-spacing: 0.02em;
}
.nav-link:hover, .nav-link.active { color: var(--text-primary); }

/* --- BUTTONS --- */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.55rem 1.25rem;
  background: var(--gold);
  color: #0d0d0f;
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
  text-decoration: none;
  letter-spacing: 0.01em;
}
.btn-primary:hover {
  background: var(--gold-light);
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(201,168,76,0.3);
}
.btn-primary.btn-lg {
  padding: 0.85rem 2rem;
  font-size: 1rem;
}
.btn-primary.btn-full { width: 100%; justify-content: center; }

.btn-ghost {
  display: inline-flex;
  align-items: center;
  padding: 0.85rem 1.75rem;
  border: 1px solid var(--border-hover);
  border-radius: var(--radius-sm);
  font-size: 1rem;
  color: var(--text-secondary);
  transition: color 0.2s, border-color 0.2s;
}
.btn-ghost:hover { color: var(--text-primary); border-color: var(--gold); }

/* --- HERO (index) --- */
.hero {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 7rem 2rem 5rem;
  text-align: center;
}

.hero-eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--gold);
  background: var(--gold-dim);
  border: 1px solid rgba(201,168,76,0.25);
  padding: 0.35rem 0.9rem;
  border-radius: 100px;
  margin-bottom: 1.5rem;
  animation: fadeUp 0.6s ease both;
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 900;
  margin-bottom: 1.25rem;
  animation: fadeUp 0.6s 0.1s ease both;
}

.accent { color: var(--gold); }

.hero-sub {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto 2.5rem;
  animation: fadeUp 0.6s 0.2s ease both;
}

.hero-cta {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeUp 0.6s 0.3s ease both;
}

/* --- PAGE HERO (inner pages) --- */
.page-hero {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 5rem 2rem 3rem;
  text-align: center;
}
.page-hero .hero-title { font-size: clamp(2rem, 5vw, 3.5rem); }

/* --- STATS --- */
.stats-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 2rem 5rem;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 2rem;
  text-align: center;
  transition: border-color 0.2s, transform 0.2s;
  animation: fadeUp 0.5s var(--delay, 0s) ease both;
}
.stat-card:hover {
  border-color: var(--gold);
  transform: translateY(-3px);
  box-shadow: var(--shadow-glow);
}

.stat-number {
  display: block;
  font-family: var(--font-display);
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--gold);
}

.stat-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-top: 0.25rem;
}

/* --- WHY SECTION --- */
.why-section {
  background: var(--bg-card);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: 5rem 2rem;
}

.why-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 5rem;
  align-items: center;
}

.section-tag {
  font-size: 0.78rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--gold);
  font-weight: 500;
  margin-bottom: 1rem;
}

.why-text h2 {
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  margin-bottom: 1rem;
}

.why-text p {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.8;
}

.benefits-list {
  list-style: none;
  margin-bottom: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.benefits-list li {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-size: 0.95rem;
  color: var(--text-secondary);
}

.check {
  color: var(--gold);
  font-weight: 700;
}

/* Card stack visual */
.why-visual { display: flex; justify-content: center; align-items: center; }

.card-stack {
  position: relative;
  width: 280px;
  height: 200px;
}

.demo-card {
  position: absolute;
  width: 260px;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
}

.dc-back  { top: 0;   left: 30px; transform: rotate(6deg);  opacity: 0.4; }
.dc-mid   { top: 15px; left: 15px; transform: rotate(3deg);  opacity: 0.65; }
.dc-front { top: 30px; left: 0;   transform: rotate(-1deg); opacity: 1; box-shadow: var(--shadow-card); border-color: var(--border-hover); }

.card-tag {
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--gold);
  display: block;
  margin-bottom: 0.5rem;
}

.demo-card p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-bottom: 0.75rem;
}

.card-answer {
  font-family: var(--font-display);
  font-size: 1.1rem;
  color: var(--text-primary);
  border-top: 1px solid var(--border);
  padding-top: 0.6rem;
}

/* --- STEPS (flash.html) --- */
.steps-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 2rem 2rem 6rem;
}

.steps-grid {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-bottom: 4rem;
}

.step-card {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: start;
  gap: 2rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  transition: border-color 0.2s, box-shadow 0.2s;
  animation: fadeUp 0.5s var(--delay, 0s) ease both;
}
.step-card:hover {
  border-color: var(--gold);
  box-shadow: var(--shadow-glow);
}

.step-connector {
  width: 2px;
  height: 2.5rem;
  background: linear-gradient(to bottom, var(--border-hover), transparent);
  margin-left: 3.25rem;
}

.step-number {
  font-family: var(--font-display);
  font-size: 2.75rem;
  font-weight: 900;
  color: var(--gold);
  line-height: 1;
  min-width: 2.5rem;
  opacity: 0.7;
}

.step-content h3 {
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
}

.step-content p {
  color: var(--text-secondary);
  line-height: 1.8;
}

.step-icon {
  font-size: 2rem;
  opacity: 0.6;
}

.steps-cta {
  text-align: center;
}
.steps-cta p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

/* --- QUIZ (quiz.html) --- */
.quiz-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 2rem 2rem 6rem;
}

.quiz-layout {
  display: grid;
  grid-template-columns: 380px 1fr;
  gap: 2rem;
  align-items: start;
}

.create-panel, .cards-panel {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem;
}

.panel-title {
  font-family: var(--font-display);
  font-size: 1.35rem;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.card-count {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  background: var(--gold-dim);
  color: var(--gold);
  border-radius: 50%;
  font-size: 0.8rem;
  font-family: var(--font-body);
  font-weight: 600;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  margin-bottom: 1.25rem;
}

.form-group label {
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.form-group input,
.form-group textarea {
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.95rem;
  resize: vertical;
  transition: border-color 0.2s, box-shadow 0.2s;
  outline: none;
}

.form-group input::placeholder,
.form-group textarea::placeholder { color: var(--text-muted); }

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--gold);
  box-shadow: 0 0 0 3px var(--gold-dim);
}

/* Saved cards list */
.cards-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-height: 520px;
  overflow-y: auto;
  padding-right: 0.25rem;
}

.cards-list::-webkit-scrollbar { width: 4px; }
.cards-list::-webkit-scrollbar-track { background: transparent; }
.cards-list::-webkit-scrollbar-thumb { background: var(--border-hover); border-radius: 4px; }

.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
  padding: 3rem 1rem;
  color: var(--text-muted);
  text-align: center;
}
.empty-icon { font-size: 2.5rem; opacity: 0.4; }

/* Individual flash card (generated by JS) */
.flash-card-item {
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  transition: border-color 0.2s;
  animation: fadeUp 0.3s ease both;
}
.flash-card-item:hover { border-color: var(--border-hover); }

.flash-card-subject {
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 0.4rem;
}

.flash-card-question {
  font-size: 0.95rem;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
  font-weight: 500;
}

.flash-card-answer {
  font-size: 0.875rem;
  color: var(--text-secondary);
  border-top: 1px solid var(--border);
  padding-top: 0.6rem;
  margin-top: 0.4rem;
  display: none;
}

.flash-card-answer.visible { display: block; }

.card-actions {
  display: flex;
  gap: 0.5rem;
  margin-top: 0.75rem;
}

.btn-reveal, .btn-delete {
  font-size: 0.78rem;
  font-weight: 500;
  padding: 0.3rem 0.75rem;
  border-radius: 6px;
  border: 1px solid var(--border);
  cursor: pointer;
  transition: all 0.15s;
  background: transparent;
}

.btn-reveal {
  color: var(--gold);
  border-color: rgba(201,168,76,0.3);
}
.btn-reveal:hover { background: var(--gold-dim); }

.btn-delete {
  color: var(--text-muted);
}
.btn-delete:hover { color: #e05f5f; border-color: rgba(224,95,95,0.3); background: rgba(224,95,95,0.08); }

/* --- FOOTER --- */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg-card);
  padding: 3rem 2rem 0;
}

.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 2rem;
  padding-bottom: 2.5rem;
}

.footer-brand p {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 0.5rem;
}

.footer-links {
  display: flex;
  gap: 1.75rem;
  flex-wrap: wrap;
}

.footer-links a {
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--gold); }

.footer-bottom {
  max-width: var(--max-w);
  margin: 0 auto;
  border-top: 1px solid var(--border);
  padding: 1.25rem 0;
}

.footer-bottom p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* --- ANIMATIONS --- */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(18px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* --- RESPONSIVE --- */
@media (max-width: 768px) {
  .stats-grid { grid-template-columns: 1fr; }

  .why-inner {
    grid-template-columns: 1fr;
    gap: 3rem;
  }
  .why-visual { display: none; }

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

  .step-card {
    grid-template-columns: auto 1fr;
  }
  .step-icon { display: none; }

  .footer-inner { flex-direction: column; gap: 1.5rem; }
  .footer-links { gap: 1rem; }

  .hero { padding: 4rem 1.25rem 3rem; }
  .page-hero { padding: 3rem 1.25rem 2rem; }
}

@media (max-width: 480px) {
  .main-nav .nav-link { display: none; }
  .hero-cta { flex-direction: column; align-items: center; }
}