:root {
  --ink: #07110c;
  --ink-2: #102117;
  --paper: #f4f1e8;
  --card: rgba(255, 255, 255, 0.04);
  --line: rgba(197, 240, 122, 0.22);
  --lime: #c6f25a;
  --lime-2: #e7ffb0;
  --muted: #b7c4b4;
  --text: #f3f6ef;
  --max: 1120px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(900px 420px at 85% -10%, rgba(198, 242, 90, 0.16), transparent 60%),
    radial-gradient(700px 380px at -10% 20%, rgba(120, 210, 190, 0.08), transparent 55%),
    var(--ink);
  font-family: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  line-height: 1.7;
}

body::before {
  content: "";
  pointer-events: none;
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(198, 242, 90, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(198, 242, 90, 0.045) 1px, transparent 1px);
  background-size: 72px 72px;
  mask-image: radial-gradient(circle at 50% 20%, black, transparent 78%);
}

a { color: inherit; }

img { max-width: 100%; display: block; }

.wrap {
  width: min(var(--max), calc(100% - 48px));
  margin: 0 auto;
  position: relative;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(7, 17, 12, 0.78);
  border-bottom: 1px solid rgba(198, 242, 90, 0.14);
  backdrop-filter: blur(16px);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 74px;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.brand .mascot {
  position: relative;
  width: 40px;
  height: 40px;
  flex: none;
  border-radius: 50%;
  background: var(--lime);
  box-shadow: 0 0 0 6px rgba(198, 242, 90, 0.12);
  transform-origin: 50% 56%;
  animation: mascot-sway 2.8s linear infinite;
}

.brand .mascot img {
  display: block;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  object-fit: cover;
}

.brand .mascot .mascot-blink {
  position: absolute;
  inset: 0;
  opacity: 0;
  animation: mascot-blink 2.8s linear infinite;
}

.header-tools { display: flex; align-items: center; gap: 22px; }

.header-cta {
  color: var(--ink);
  background: var(--lime);
  text-decoration: none;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.04em;
  padding: 8px 14px;
  border-radius: 999px;
  white-space: nowrap;
}

.nav { display: flex; gap: 22px; font-size: 14px; letter-spacing: 0.04em; }

.lang {
  color: var(--lime);
  text-decoration: none;
  font-size: 14px;
  letter-spacing: 0.06em;
  white-space: nowrap;
}

.nav a { text-decoration: none; color: var(--muted); }

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

.hero {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 56px;
  align-items: center;
  padding: 72px 0 28px;
}

.kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 18px;
  color: var(--lime);
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 13px;
  letter-spacing: 0.16em;
}

.kicker::before {
  content: "";
  width: 18px;
  height: 1px;
  background: var(--lime);
}

h1 {
  margin: 0;
  font-size: 76px;
  line-height: 0.95;
  letter-spacing: -0.05em;
}

.hero h1.en-name {
  font-size: 58px;
  letter-spacing: -0.045em;
}

.hero h1 span {
  display: block;
  margin-top: 8px;
  color: transparent;
  -webkit-text-stroke: 1.5px var(--lime-2);
  font-size: 0.72em;
  line-height: 1.05;
}

.lede {
  max-width: 460px;
  margin: 22px 0 28px;
  color: var(--muted);
  font-size: 17px;
}

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

.button {
  display: inline-block;
  padding: 12px 18px;
  border-radius: 999px;
  background: var(--lime);
  color: var(--ink);
  text-decoration: none;
  font-weight: 700;
}

.button.secondary {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--line);
}

.board {
  position: relative;
  background:
    linear-gradient(180deg, rgba(198, 242, 90, 0.08), transparent 28%),
    #0c1812;
  border: 1px solid var(--line);
  border-radius: 28px;
  padding: 22px 22px 8px;
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.35);
  overflow: hidden;
}

.board::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--lime), transparent);
  animation: scan 4.8s linear infinite;
}

.board header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 8px;
}

.board header strong { font-size: 18px; }

.board header span {
  color: var(--lime);
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 12px;
  letter-spacing: 0.08em;
}

.step {
  display: grid;
  grid-template-columns: 72px 1fr;
  gap: 12px;
  padding: 16px 0;
  border-top: 1px solid rgba(198, 242, 90, 0.12);
}

.step b {
  color: var(--lime);
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 13px;
}

.step p { margin: 0; }

.bento > article:last-child { grid-column: 1 / -1; }

.formula {
  display: block;
  margin: 6px 0 0;
  color: var(--lime-2);
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  letter-spacing: 0.04em;
}

section { padding: 36px 0 8px; }

.section-label {
  margin: 0 0 8px;
  color: var(--lime);
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 12px;
  letter-spacing: 0.18em;
}

h2 {
  margin: 0 0 10px;
  font-size: 40px;
  letter-spacing: -0.04em;
}

.section-lead {
  margin: 0 0 22px;
  max-width: 640px;
  color: var(--muted);
}

.bento {
  display: grid;
  grid-template-columns: 1.35fr 0.85fr;
  gap: 14px;
}

.card {
  background: var(--card);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 24px;
  padding: 22px;
}

.card h3 { margin: 0 0 8px; font-size: 22px; }

.card p { margin: 0; color: var(--muted); }

.feature-main {
  min-height: 280px;
  background:
    linear-gradient(160deg, rgba(198, 242, 90, 0.14), transparent 42%),
    #101910;
}

.trace {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.trace div {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 8px;
  border-bottom: 1px dashed rgba(198, 242, 90, 0.25);
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 13px;
}

.stack { display: grid; gap: 14px; }

.flash {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-top: 16px;
}

.flash span {
  display: grid;
  place-items: center;
  min-height: 72px;
  border-radius: 16px;
  background: var(--ink);
  border: 1px solid var(--line);
  color: var(--lime);
  font-weight: 700;
}

.flash span:last-child {
  background: var(--lime);
  color: var(--ink);
}

.note-lines {
  margin-top: 14px;
  height: 74px;
  border-radius: 16px;
  background:
    repeating-linear-gradient(
      transparent,
      transparent 17px,
      rgba(198, 242, 90, 0.25) 18px
    );
}

.path {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin-top: 8px;
}

.path article {
  position: relative;
  padding: 22px 18px 8px;
  border-top: 1px solid var(--lime);
}

.path .num {
  font-family: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  color: var(--lime);
  font-size: 13px;
  letter-spacing: 0.14em;
}

.agent {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 36px;
  align-items: center;
  margin-top: 28px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 32px;
  background:
    radial-gradient(420px 220px at 12% 20%, rgba(198, 242, 90, 0.16), transparent 70%),
    #0c1812;
}

.agent-face {
  width: 96px;
  height: 96px;
  margin: 8px 0 12px;
  border-radius: 50%;
  object-fit: cover;
  background: var(--lime);
  box-shadow: 0 0 0 10px rgba(198, 242, 90, 0.12);
}

.dialogue { display: grid; gap: 12px; }

.bubble {
  margin: 0;
  padding: 16px 18px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.04);
}

.bubble b {
  display: block;
  margin-bottom: 6px;
  font-size: 12px;
  letter-spacing: 0.12em;
}

.bubble.you { border: 1px solid rgba(255, 255, 255, 0.08); }

.bubble.yi {
  background: rgba(198, 242, 90, 0.1);
  border: 1px solid var(--line);
}

.bubble.yi b { color: var(--lime); }

.about {
  display: grid;
  grid-template-columns: 1.25fr 0.75fr;
  gap: 14px;
  margin: 12px 0 56px;
}

.legal {
  margin: 28px auto 64px;
  padding: 36px 32px 48px;
  border-radius: 28px;
  background: var(--paper);
  color: #1a1a1a;
}

.legal h1 { font-size: 40px; color: #1a1a1a; }

.legal h2 { font-size: 22px; margin-top: 28px; }

.legal a { color: #2f6b22; }

.legal ul { padding-left: 1.2em; }

.site-footer {
  border-top: 1px solid rgba(198, 242, 90, 0.14);
  padding: 28px 0 40px;
  color: var(--muted);
  font-size: 14px;
}

.site-footer .wrap {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 18px;
}

.site-footer strong { color: var(--text); }

.site-footer a { color: var(--lime); }

@keyframes scan {
  from { top: 18%; }
  to { top: 88%; }
}

@keyframes mascot-sway {
  0% { transform: translateY(0) rotate(0deg); }
  12.5% { transform: translateY(0.51px) rotate(2.43deg); }
  25% { transform: translateY(0.72px) rotate(3.44deg); }
  37.5% { transform: translateY(0.51px) rotate(2.43deg); }
  50% { transform: translateY(0) rotate(0deg); }
  62.5% { transform: translateY(-0.51px) rotate(-2.43deg); }
  75% { transform: translateY(-0.72px) rotate(-3.44deg); }
  87.5% { transform: translateY(-0.51px) rotate(-2.43deg); }
  100% { transform: translateY(0) rotate(0deg); }
}

@keyframes mascot-blink {
  0%, 39.9% { opacity: 0; }
  40%, 47.9% { opacity: 1; }
  48%, 100% { opacity: 0; }
}

@media (prefers-reduced-motion: reduce) {
  .board::after { animation: none; top: 30%; }
  .brand .mascot,
  .brand .mascot .mascot-blink { animation: none; }
}

@media (max-width: 860px) {
  .hero, .bento, .path, .about, .agent, .site-footer .wrap, .flash {
    grid-template-columns: 1fr;
  }

  h1 { font-size: 52px; }

  .hero h1.en-name { font-size: 40px; }

  .nav { display: none; }

  .legal { padding: 24px 18px 32px; }
}