:root {
  --ink: #17212b;
  --muted: #5f6c7b;
  --paper: #fffaf1;
  --surface: #ffffff;
  --line: #d9e1df;
  --mint: #78c8b5;
  --coral: #f16c5b;
  --gold: #f6c74c;
  --blue: #4f7fbe;
  --green: #5aa66a;
  --shadow: 0 22px 60px rgba(21, 32, 43, 0.16);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    linear-gradient(135deg, rgba(120, 200, 181, 0.22), transparent 34%),
    linear-gradient(315deg, rgba(246, 199, 76, 0.2), transparent 32%),
    var(--paper);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "Microsoft YaHei", sans-serif;
  line-height: 1.6;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  padding: 0 clamp(20px, 5vw, 72px);
  background: rgba(255, 250, 241, 0.86);
  border-bottom: 1px solid rgba(23, 33, 43, 0.08);
  backdrop-filter: blur(18px);
}

.brand,
.nav-links,
.hero-actions {
  display: flex;
  align-items: center;
}

.brand {
  gap: 12px;
  font-weight: 800;
  letter-spacing: 0;
}

.brand-mark {
  display: grid;
  width: 38px;
  height: 38px;
  place-items: center;
  color: #ffffff;
  background: var(--ink);
  border-radius: 8px;
  box-shadow: 6px 6px 0 var(--gold);
}

.nav-links {
  gap: clamp(14px, 3vw, 32px);
  color: var(--muted);
  font-size: 0.95rem;
  font-weight: 700;
}

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

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(340px, 0.78fr);
  gap: clamp(36px, 7vw, 88px);
  align-items: center;
  min-height: calc(100vh - 72px);
  padding: clamp(44px, 7vw, 88px) clamp(20px, 5vw, 72px) clamp(28px, 5vw, 56px);
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--coral);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 760px;
  margin-bottom: 20px;
  font-size: clamp(4rem, 12vw, 9.5rem);
  line-height: 0.85;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 0;
  font-size: clamp(2rem, 5vw, 4.2rem);
  line-height: 1;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 12px;
  font-size: clamp(1.2rem, 2vw, 1.6rem);
  line-height: 1.2;
}

.hero-lead {
  max-width: 650px;
  margin-bottom: 28px;
  color: #344252;
  font-size: clamp(1.05rem, 2vw, 1.35rem);
}

.hero-actions {
  flex-wrap: wrap;
  gap: 12px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 20px;
  border: 2px solid var(--ink);
  border-radius: 8px;
  font-weight: 850;
  box-shadow: 4px 4px 0 var(--ink);
  transition: transform 180ms ease, box-shadow 180ms ease, background 180ms ease;
}

.button:hover {
  transform: translate(2px, 2px);
  box-shadow: 2px 2px 0 var(--ink);
}

.button.primary {
  background: var(--gold);
}

.button.ghost {
  background: rgba(255, 255, 255, 0.62);
}

.hero-showcase {
  display: grid;
  place-items: center;
}

.device-frame {
  width: min(100%, 430px);
  padding: 18px;
  background: #1b2733;
  border: 3px solid var(--ink);
  border-radius: 28px;
  box-shadow: var(--shadow), 10px 10px 0 var(--mint);
}

.game-topbar,
.tray {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.game-topbar {
  color: #f7f2e8;
  padding: 8px 8px 16px;
  font-size: 0.9rem;
  font-weight: 800;
}

.puzzle-board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  aspect-ratio: 1;
  padding: 12px;
  background: #f8f0e1;
  border-radius: 18px;
  overflow: hidden;
}

.piece {
  position: relative;
  min-width: 0;
  border: 2px solid rgba(23, 33, 43, 0.82);
  border-radius: 15px;
  box-shadow: inset 0 -14px 0 rgba(0, 0, 0, 0.08);
}

.piece::before,
.piece::after {
  content: "";
  position: absolute;
  width: 28%;
  aspect-ratio: 1;
  background: inherit;
  border: 2px solid rgba(23, 33, 43, 0.82);
  border-radius: 50%;
}

.piece::before {
  top: 36%;
  right: -17%;
}

.piece::after {
  left: 36%;
  bottom: -17%;
}

.p1 { background: var(--coral); }
.p2 { background: var(--gold); transform: translateY(8px); }
.p3 { background: var(--blue); }
.p4 { background: var(--mint); transform: translateX(-6px); }
.p5 { background: #f3f0ea; }
.p6 { background: var(--green); transform: translateY(-6px); }
.p7 { background: #9c7bdc; }
.p8 { background: #ff9d73; transform: translateY(7px); }
.p9 { background: #67b7dc; }

.tray {
  gap: 12px;
  padding: 18px 10px 2px;
}

.tray span {
  flex: 1;
  height: 48px;
  border: 2px dashed rgba(255, 255, 255, 0.38);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.08);
}

.section {
  padding: clamp(56px, 8vw, 110px) clamp(20px, 5vw, 72px);
}

.intro-band {
  background: #ffffff;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.section-heading {
  max-width: 900px;
  margin-bottom: clamp(28px, 5vw, 56px);
}

.game-feature {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 420px);
  gap: clamp(24px, 5vw, 58px);
  align-items: start;
}

.game-copy {
  max-width: 730px;
}

.game-copy p,
.principles p,
.contact-section h2 {
  color: var(--muted);
}

.feature-list {
  display: grid;
  gap: 12px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.feature-list li {
  position: relative;
  padding-left: 30px;
  font-weight: 750;
}

.feature-list li::before {
  content: "";
  position: absolute;
  top: 0.62em;
  left: 0;
  width: 14px;
  height: 14px;
  background: var(--mint);
  border: 2px solid var(--ink);
  border-radius: 4px;
}

.stats-panel {
  display: grid;
  gap: 12px;
}

.stats-panel div,
.principles article {
  background: var(--surface);
  border: 2px solid var(--ink);
  border-radius: 8px;
  box-shadow: 5px 5px 0 rgba(23, 33, 43, 0.12);
}

.stats-panel div {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 18px;
}

.stats-panel strong {
  font-size: 0.78rem;
  letter-spacing: 0;
  text-transform: uppercase;
}

.stats-panel span {
  color: var(--muted);
  font-weight: 750;
  text-align: right;
}

.studio-section {
  background:
    linear-gradient(90deg, rgba(241, 108, 91, 0.08), transparent 38%),
    #f7fbf9;
}

.principles {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.principles article {
  padding: 24px;
}

.principle-icon {
  display: inline-grid;
  width: 44px;
  height: 44px;
  margin-bottom: 28px;
  place-items: center;
  color: var(--ink);
  background: var(--gold);
  border: 2px solid var(--ink);
  border-radius: 8px;
  font-weight: 900;
}

.contact-section {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 24px;
  align-items: center;
  padding: clamp(44px, 7vw, 78px) clamp(20px, 5vw, 72px);
  background: var(--ink);
  color: #ffffff;
}

.contact-section h2 {
  max-width: 760px;
  color: #f8f0e1;
}

.contact-section .button {
  color: var(--ink);
}

@media (max-width: 860px) {
  .site-header {
    min-height: 64px;
  }

  .nav-links {
    display: none;
  }

  .hero,
  .game-feature,
  .contact-section {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
    padding-top: 44px;
  }

  .hero-showcase {
    justify-items: start;
  }

  .principles {
    grid-template-columns: 1fr;
  }

  .contact-section {
    justify-items: start;
  }
}

@media (max-width: 520px) {
  .brand span:last-child {
    max-width: 150px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  h1 {
    font-size: clamp(3.4rem, 18vw, 5.5rem);
  }

  .button {
    width: 100%;
  }

  .device-frame {
    border-radius: 22px;
    box-shadow: var(--shadow), 7px 7px 0 var(--mint);
  }

  .stats-panel div {
    display: grid;
  }

  .stats-panel span {
    text-align: left;
  }
}