/* ============================================
   ChessLoops — Global Styles
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Playfair+Display:ital,wght@0,400;0,700;0,900;1,400&family=DM+Sans:ital,wght@0,400;0,500;0,700;1,400&display=swap');

:root {
  --black: #0a0a0a;
  --black-rich: #0d0f0e;
  --dark: #141816;
  --dark-elevated: #1a1e1c;
  --dark-border: #2a2e2c;
  --green-deep: #1a3a2a;
  --green-felt: #2d5a3f;
  --green-accent: #4a9e6e;
  --green-bright: #5cb87a;
  --gold: #c8a44e;
  --gold-light: #dbb964;
  --gold-dim: #a08035;
  --cream: #f0e6d0;
  --cream-soft: #e8dcc4;
  --white: #f5f2ed;
  --white-muted: #b8b4ae;
  --white-dim: #787572;
  --font-display: 'Playfair Display', Georgia, serif;
  --font-body: 'DM Sans', system-ui, sans-serif;
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-out-back: cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  background: var(--black-rich);
  color: var(--white);
  line-height: 1.6;
  overflow-x: hidden;
}

a {
  color: var(--gold);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--gold-light);
}

/* ============================================
   Noise Texture Overlay
   ============================================ */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  opacity: 0.03;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: 9999;
}

/* ============================================
   Navigation
   ============================================ */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 1.25rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: linear-gradient(to bottom, rgba(10,10,10,0.95), rgba(10,10,10,0));
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--white);
}

.nav-logo-icon {
  font-size: 1.75rem;
  line-height: 1;
}

.nav-logo-text {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.nav-logo-text span {
  color: var(--gold);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  color: var(--white-muted);
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  transition: color 0.25s ease;
}

.nav-links a:hover {
  color: var(--white);
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8rem 2rem 6rem;
  overflow: hidden;
}

.hero-board-bg {
  position: absolute;
  inset: 0;
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  grid-template-rows: repeat(8, 1fr);
  opacity: 0.04;
  transform: perspective(800px) rotateX(45deg) scale(1.8);
  transform-origin: center 30%;
}

.hero-board-bg .sq {
  aspect-ratio: 1;
}

.hero-board-bg .sq-dark {
  background: var(--green-felt);
}

.hero-gradient {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 50% at 50% 40%, rgba(42,90,63,0.15) 0%, transparent 70%),
    radial-gradient(ellipse 40% 30% at 30% 60%, rgba(200,164,78,0.06) 0%, transparent 60%),
    linear-gradient(to bottom, transparent 60%, var(--black-rich));
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 800px;
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1rem;
  margin-bottom: 2rem;
  border: 1px solid var(--dark-border);
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--white-muted);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  opacity: 0;
  animation: fadeUp 0.8s var(--ease-out-expo) 0.2s forwards;
}

.hero-badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--green-accent);
  animation: pulse 2s ease infinite;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(3rem, 7vw, 5.5rem);
  font-weight: 900;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
  opacity: 0;
  animation: fadeUp 0.8s var(--ease-out-expo) 0.35s forwards;
}

.hero h1 .accent {
  color: var(--gold);
  font-style: italic;
}

.hero h1 .piece {
  display: inline-block;
  color: var(--green-accent);
  animation: float 4s ease-in-out infinite;
}

.hero-subtitle {
  font-size: clamp(1.05rem, 2vw, 1.25rem);
  color: var(--white-muted);
  max-width: 560px;
  margin: 0 auto 2.5rem;
  line-height: 1.7;
  opacity: 0;
  animation: fadeUp 0.8s var(--ease-out-expo) 0.5s forwards;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.25rem;
  flex-wrap: wrap;
  opacity: 0;
  animation: fadeUp 0.8s var(--ease-out-expo) 0.65s forwards;
}

/* ============================================
   Buttons
   ============================================ */
.btn-appstore {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.9rem 1.75rem;
  background: var(--white);
  color: var(--black);
  border-radius: 14px;
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 700;
  text-decoration: none;
  transition: all 0.3s var(--ease-out-expo);
  box-shadow: 0 0 0 0 rgba(245,242,237,0.1);
}

.btn-appstore:hover {
  color: var(--black);
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(245,242,237,0.12);
}

.btn-appstore svg {
  width: 22px;
  height: 22px;
}

.btn-appstore .btn-text-sub {
  font-size: 0.65rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  opacity: 0.6;
  display: block;
  text-align: left;
}

.btn-appstore .btn-text-main {
  display: block;
  text-align: left;
  line-height: 1.1;
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.9rem 1.75rem;
  border: 1px solid var(--dark-border);
  border-radius: 14px;
  color: var(--white-muted);
  font-size: 0.95rem;
  font-weight: 500;
  text-decoration: none;
  transition: all 0.3s var(--ease-out-expo);
}

.btn-outline:hover {
  color: var(--white);
  border-color: var(--white-dim);
  background: rgba(255,255,255,0.03);
}

/* ============================================
   Section Commons
   ============================================ */
.section {
  padding: 6rem 2rem;
  position: relative;
}

.section-inner {
  max-width: 1100px;
  margin: 0 auto;
}

.section-label {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 1rem;
}

.section-heading {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--white-muted);
  max-width: 600px;
  line-height: 1.7;
}

/* ============================================
   Method Section
   ============================================ */
.method {
  background: var(--dark);
  border-top: 1px solid var(--dark-border);
  border-bottom: 1px solid var(--dark-border);
}

.method-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
  margin-top: 3rem;
}

.method-visual {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
}

.method-loop {
  position: relative;
  width: 280px;
  height: 280px;
}

.method-loop-ring {
  position: absolute;
  inset: 0;
  border: 2px solid var(--dark-border);
  border-radius: 50%;
  border-top-color: var(--gold);
  animation: spin 8s linear infinite;
}

.method-loop-ring:nth-child(2) {
  inset: 25px;
  border-top-color: var(--green-accent);
  animation-duration: 6s;
  animation-direction: reverse;
}

.method-loop-ring:nth-child(3) {
  inset: 50px;
  border-top-color: var(--gold-dim);
  animation-duration: 10s;
}

.method-loop-center {
  position: absolute;
  inset: 75px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: var(--dark-elevated);
  border-radius: 50%;
  border: 1px solid var(--dark-border);
}

.method-loop-number {
  font-family: var(--font-display);
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--gold);
  line-height: 1;
}

.method-loop-label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--white-dim);
  margin-top: 0.25rem;
}

.method-steps {
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

.method-step {
  display: flex;
  gap: 1.25rem;
  align-items: flex-start;
}

.method-step-num {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--dark-border);
  border-radius: 10px;
  font-family: var(--font-display);
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--gold);
}

.method-step h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.method-step p {
  font-size: 0.9rem;
  color: var(--white-muted);
  line-height: 1.6;
}

/* ============================================
   Levels Section
   ============================================ */
.levels-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 1rem;
  margin-top: 3rem;
}

.level-card {
  position: relative;
  padding: 1.75rem 1.25rem;
  background: var(--dark);
  border: 1px solid var(--dark-border);
  border-radius: 16px;
  text-align: center;
  transition: all 0.4s var(--ease-out-expo);
  overflow: hidden;
}

.level-card::before {
  content: '';
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity 0.4s ease;
  border-radius: 16px;
}

.level-card:hover {
  transform: translateY(-4px);
  border-color: transparent;
}

.level-card:hover::before {
  opacity: 1;
}

.level-card:nth-child(1)::before { background: linear-gradient(135deg, rgba(74,158,110,0.1), transparent); }
.level-card:nth-child(1):hover { border-color: rgba(74,158,110,0.3); }
.level-card:nth-child(2)::before { background: linear-gradient(135deg, rgba(78,140,200,0.1), transparent); }
.level-card:nth-child(2):hover { border-color: rgba(78,140,200,0.3); }
.level-card:nth-child(3)::before { background: linear-gradient(135deg, rgba(200,164,78,0.1), transparent); }
.level-card:nth-child(3):hover { border-color: rgba(200,164,78,0.3); }
.level-card:nth-child(4)::before { background: linear-gradient(135deg, rgba(200,120,78,0.1), transparent); }
.level-card:nth-child(4):hover { border-color: rgba(200,120,78,0.3); }
.level-card:nth-child(5)::before { background: linear-gradient(135deg, rgba(180,78,200,0.1), transparent); }
.level-card:nth-child(5):hover { border-color: rgba(180,78,200,0.3); }

.level-piece {
  font-size: 2.5rem;
  line-height: 1;
  margin-bottom: 0.75rem;
  position: relative;
  z-index: 1;
}

.level-name {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
  position: relative;
  z-index: 1;
}

.level-rating {
  font-size: 0.8rem;
  color: var(--white-dim);
  font-weight: 500;
  position: relative;
  z-index: 1;
}

.level-phases {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.35rem;
  margin-top: 0.85rem;
  position: relative;
  z-index: 1;
}

.level-phase-tag {
  font-size: 0.65rem;
  padding: 0.2rem 0.5rem;
  border-radius: 6px;
  background: rgba(255,255,255,0.05);
  color: var(--white-dim);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

/* ============================================
   Features Section
   ============================================ */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 3rem;
}

.feature-card {
  padding: 2rem 1.75rem;
  background: var(--dark);
  border: 1px solid var(--dark-border);
  border-radius: 16px;
  transition: border-color 0.3s ease;
}

.feature-card:hover {
  border-color: var(--dark-border);
}

.feature-icon {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--dark-elevated);
  border: 1px solid var(--dark-border);
  border-radius: 12px;
  font-size: 1.2rem;
  margin-bottom: 1.25rem;
}

.feature-card h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

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

/* ============================================
   CTA Section
   ============================================ */
.cta {
  text-align: center;
  padding: 8rem 2rem;
  position: relative;
}

.cta::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 50% 60% at 50% 50%, rgba(42,90,63,0.1) 0%, transparent 70%);
  pointer-events: none;
}

.cta-piece {
  font-size: 4rem;
  display: block;
  margin-bottom: 1.5rem;
  opacity: 0.3;
}

.cta h2 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.cta p {
  color: var(--white-muted);
  font-size: 1.05rem;
  margin-bottom: 2.5rem;
  max-width: 450px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.7;
}

/* ============================================
   Footer
   ============================================ */
.footer {
  border-top: 1px solid var(--dark-border);
  padding: 3rem 2rem;
}

.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--white-dim);
  font-size: 0.85rem;
}

.footer-brand span {
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--white-muted);
}

.footer-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.footer-links a {
  color: var(--white-dim);
  font-size: 0.85rem;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: var(--white);
}

/* ============================================
   Legal Pages
   ============================================ */
.legal-page {
  padding: 8rem 2rem 4rem;
}

.legal-inner {
  max-width: 740px;
  margin: 0 auto;
}

.legal-inner h1 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 700;
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

.legal-date {
  color: var(--white-dim);
  font-size: 0.85rem;
  margin-bottom: 3rem;
}

.legal-inner h2 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  margin-top: 2.5rem;
  margin-bottom: 0.75rem;
  color: var(--cream);
}

.legal-inner p {
  color: var(--white-muted);
  font-size: 0.95rem;
  line-height: 1.75;
  margin-bottom: 1rem;
}

.legal-inner ul {
  color: var(--white-muted);
  font-size: 0.95rem;
  line-height: 1.75;
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

.legal-inner li {
  margin-bottom: 0.4rem;
}

.legal-inner a {
  color: var(--gold);
}

/* ============================================
   Animations
   ============================================ */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-6px); }
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ============================================
   Scroll Reveal
   ============================================ */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s var(--ease-out-expo), transform 0.7s var(--ease-out-expo);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 900px) {
  .levels-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .features-grid {
    grid-template-columns: 1fr 1fr;
  }
  .method-grid {
    grid-template-columns: 1fr;
    gap: 3rem;
  }
  .method-visual {
    order: -1;
  }
}

@media (max-width: 640px) {
  .nav {
    padding: 1rem 1.25rem;
  }
  .nav-links {
    gap: 1rem;
  }
  .nav-links a {
    font-size: 0.8rem;
  }
  .hero {
    padding: 7rem 1.25rem 4rem;
  }
  .section {
    padding: 4rem 1.25rem;
  }
  .levels-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .levels-grid .level-card:last-child {
    grid-column: 1 / -1;
    max-width: 50%;
    justify-self: center;
  }
  .features-grid {
    grid-template-columns: 1fr;
  }
  .footer-inner {
    flex-direction: column;
    text-align: center;
  }
  .hero-actions {
    flex-direction: column;
  }
}