/* ========================================
   BookLoop Landing Page — Theme CSS
   ======================================== */

:root {
  --bg: #0d1117;
  --bg-2: #161b22;
  --bg-3: #21262d;
  --fg: #f0f6fc;
  --fg-2: #8b949e;
  --accent: #f59e0b;
  --accent-dim: rgba(245, 158, 11, 0.12);
  --border: rgba(240, 246, 252, 0.08);
  --font-display: 'Syne', sans-serif;
  --font-body: 'DM Sans', sans-serif;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-body);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* ── Navigation ── */
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 48px;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(13, 17, 23, 0.9);
  backdrop-filter: blur(12px);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--fg);
  letter-spacing: -0.02em;
}

.nav-tagline {
  font-size: 0.8rem;
  color: var(--fg-2);
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* ── Hero ── */
.hero {
  min-height: calc(100vh - 73px);
  display: flex;
  align-items: center;
  padding: 80px 48px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 80% 60% at 70% 40%, rgba(245,158,11,0.05) 0%, transparent 60%);
  pointer-events: none;
}

.hero-inner {
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
}

.hero-badge {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  border: 1px solid rgba(245, 158, 11, 0.3);
  padding: 6px 14px;
  border-radius: 100px;
  margin-bottom: 28px;
  background: var(--accent-dim);
}

.hero-content h1 {
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 5vw, 4rem);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.03em;
  color: var(--fg);
  margin-bottom: 24px;
}

.hero-content h1 em {
  font-style: normal;
  color: var(--accent);
}

.hero-sub {
  font-size: 1.05rem;
  color: var(--fg-2);
  line-height: 1.7;
  max-width: 480px;
  margin-bottom: 48px;
}

.hero-stats {
  display: flex;
  align-items: center;
  gap: 32px;
}

.hero-stat { display: flex; flex-direction: column; }

.hero-stat-num {
  font-family: var(--font-display);
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--accent);
  letter-spacing: -0.02em;
  line-height: 1;
  margin-bottom: 4px;
}

.hero-stat-label {
  font-size: 0.75rem;
  color: var(--fg-2);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.hero-stat-divider {
  width: 1px;
  height: 48px;
  background: var(--border);
}

/* ── Hero Visual ── */
.hero-visual {
  display: flex;
  align-items: center;
  justify-content: center;
}

.loop-animation {
  position: relative;
  width: 380px;
  height: 380px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.loop-ring {
  position: absolute;
  border-radius: 50%;
  border: 1px solid rgba(245, 158, 11, 0.15);
}

.loop-ring-1 { width: 380px; height: 380px; animation: ring-pulse 4s ease-in-out infinite; }
.loop-ring-2 { width: 280px; height: 280px; border-color: rgba(245, 158, 11, 0.25); animation: ring-pulse 4s ease-in-out infinite 0.5s; }
.loop-ring-3 { width: 180px; height: 180px; border-color: rgba(245, 158, 11, 0.4); animation: ring-pulse 4s ease-in-out infinite 1s; }

@keyframes ring-pulse {
  0%, 100% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.04); opacity: 0.6; }
}

.loop-center {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.loop-label {
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-top: 4px;
}

.loop-nodes {
  position: absolute;
  inset: 0;
}

.loop-node {
  position: absolute;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  font-size: 0.7rem;
  color: var(--fg-2);
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.ln-1 { top: 20px; left: 50%; transform: translateX(-50%); }
.ln-2 { top: 50%; right: 20px; transform: translateY(-50%); }
.ln-3 { bottom: 20px; left: 50%; transform: translateX(-50%); }
.ln-4 { top: 50%; left: 20px; transform: translateY(-50%); }

.node-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--bg-2);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.node-icon::after {
  content: '';
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
}

/* ── Problem Section ── */
.problem {
  padding: 120px 48px;
  border-top: 1px solid var(--border);
}

.problem-inner { max-width: 1200px; margin: 0 auto; }

.problem-label, .features-label, .outcomes-label {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 24px;
}

.problem h2, .features h2, .outcomes h2 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.1;
  color: var(--fg);
  margin-bottom: 64px;
}

.problem h2 em, .features h2 em, .outcomes h2 em {
  font-style: normal;
  color: var(--fg-2);
}

.problem-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2px;
  margin-bottom: 56px;
  border: 1px solid var(--border);
  border-radius: 16px;
  overflow: hidden;
}

.problem-card {
  padding: 48px 40px;
  background: var(--bg-2);
  border-right: 1px solid var(--border);
}

.problem-card:last-child { border-right: none; }

.problem-stat {
  font-family: var(--font-display);
  font-size: 3rem;
  font-weight: 800;
  color: var(--accent);
  letter-spacing: -0.04em;
  line-height: 1;
  margin-bottom: 16px;
}

.problem-text {
  font-size: 0.95rem;
  color: var(--fg-2);
  line-height: 1.65;
}

.problem-closing {
  font-size: 1.1rem;
  color: var(--fg-2);
  line-height: 1.7;
  max-width: 600px;
}

/* ── Features Section ── */
.features {
  padding: 120px 48px;
  border-top: 1px solid var(--border);
  background: linear-gradient(180deg, var(--bg) 0%, var(--bg-2) 100%);
}

.features-inner { max-width: 1200px; margin: 0 auto; }

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  padding: 40px 36px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 16px;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.feature-card:hover {
  border-color: rgba(245, 158, 11, 0.3);
  transform: translateY(-2px);
}

.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  background: var(--accent-dim);
  border: 1px solid rgba(245, 158, 11, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
}

.feature-card h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--fg);
  margin-bottom: 12px;
  letter-spacing: -0.01em;
}

.feature-card p {
  font-size: 0.9rem;
  color: var(--fg-2);
  line-height: 1.65;
}

/* ── Outcomes Section ── */
.outcomes {
  padding: 120px 48px;
  border-top: 1px solid var(--border);
}

.outcomes-inner { max-width: 1200px; margin: 0 auto; }

.outcomes-grid {
  display: flex;
  align-items: center;
  gap: 32px;
  margin-bottom: 72px;
  flex-wrap: wrap;
}

.outcome-card {
  flex: 1;
  min-width: 200px;
  padding: 36px 32px;
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: 16px;
  text-align: center;
}

.oc-target {
  border-color: rgba(245, 158, 11, 0.3);
  background: var(--accent-dim);
}

.outcome-month {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--fg-2);
  margin-bottom: 12px;
}

.outcome-target {
  font-family: var(--font-display);
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--fg);
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.outcome-rev {
  font-size: 0.9rem;
  color: var(--fg-2);
}

.outcome-arrow { flex-shrink: 0; }

.outcomes-numbers {
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 40px 48px;
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: 16px;
}

.on-item { display: flex; flex-direction: column; }

.on-num {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 800;
  color: var(--fg);
  letter-spacing: -0.03em;
  line-height: 1;
  margin-bottom: 4px;
}

.on-result .on-num { color: var(--accent); }

.on-label {
  font-size: 0.78rem;
  color: var(--fg-2);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.on-divider {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--fg-2);
  flex-shrink: 0;
}

/* ── Closing Section ── */
.closing {
  padding: 120px 48px 80px;
  border-top: 1px solid var(--border);
}

.closing-inner { max-width: 900px; margin: 0 auto; text-align: center; }

.closing-rule {
  width: 60px;
  height: 3px;
  background: var(--accent);
  border-radius: 2px;
  margin: 0 auto 48px;
}

.closing h2 {
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 4vw, 3.2rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.1;
  color: var(--fg);
  margin-bottom: 32px;
}

.closing p {
  font-size: 1.05rem;
  color: var(--fg-2);
  line-height: 1.75;
  max-width: 640px;
  margin: 0 auto 48px;
}

.closing-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
}

.closing-tags span {
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.05em;
  color: var(--fg-2);
  padding: 6px 16px;
  border: 1px solid var(--border);
  border-radius: 100px;
  text-transform: uppercase;
  transition: border-color 0.2s, color 0.2s;
}

.closing-tags span:hover {
  border-color: rgba(245, 158, 11, 0.4);
  color: var(--accent);
}

/* ── Footer ── */
.footer {
  padding: 48px;
  border-top: 1px solid var(--border);
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  color: var(--fg);
}

.footer-tagline {
  font-size: 0.85rem;
  color: var(--fg-2);
}

.footer-legal {
  font-size: 0.75rem;
  color: var(--fg-2);
  opacity: 0.6;
}

/* ── Responsive ── */
@media (max-width: 900px) {
  .nav { padding: 20px 24px; }
  .hero { padding: 60px 24px; min-height: auto; }
  .hero-inner { grid-template-columns: 1fr; gap: 60px; }
  .hero-visual { display: none; }
  .hero-content h1 { font-size: 2.4rem; }
  .problem, .features, .outcomes, .closing { padding: 80px 24px; }
  .problem-grid { grid-template-columns: 1fr; }
  .problem-card { border-right: none; border-bottom: 1px solid var(--border); }
  .feature-grid { grid-template-columns: 1fr 1fr; }
  .outcomes-grid { flex-direction: column; }
  .outcomes-numbers { flex-direction: column; gap: 16px; }
  .on-divider { display: none; }
}

@media (max-width: 600px) {
  .feature-grid { grid-template-columns: 1fr; }
  .hero-stats { flex-direction: column; align-items: flex-start; gap: 16px; }
  .hero-stat-divider { display: none; }
}