:root {
  --bg: #0b0d12;
  --surface: #12151d;
  --surface-2: #181c26;
  --line: #262b38;
  --text: #e9ebf2;
  --muted: #9aa1b2;
  --accent: #7c6cff;
  --accent-2: #3ec7ff;
  --warn: #f5b84a;
  --exec: #a99bff;
  --lang: #5fd7a8;
  --math: #ffb067;
  --sci: #5fb6ff;
  --code: #ff7fb0;
  --radius: 16px;
}
@media (prefers-color-scheme: light) {
  :root {
    --bg: #f6f7fb; --surface: #ffffff; --surface-2: #f1f3f8; --line: #e1e4ec;
    --text: #141722; --muted: #5d6577; --exec: #5b49e6; --lang: #138a5e; --math: #b5600e;
    --sci: #1d6fc2; --code: #c22d6a; --warn: #a86a00;
  }
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", "Pretendard", "Apple SD Gothic Neo", "Noto Sans KR", "Malgun Gothic", sans-serif;
  -webkit-font-smoothing: antialiased; overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
.sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
.glow {
  position: fixed; inset: -20vh -10vw auto; height: 70vh; pointer-events: none; z-index: 0;
  background: radial-gradient(40% 50% at 30% 30%, color-mix(in srgb, var(--accent) 28%, transparent), transparent 70%),
              radial-gradient(35% 45% at 75% 20%, color-mix(in srgb, var(--accent-2) 20%, transparent), transparent 70%);
  filter: blur(20px);
}
.nav, main, .footer { position: relative; z-index: 1; }

.nav {
  display: flex; align-items: center; gap: 24px; max-width: 1120px; margin: 0 auto; padding: 18px 20px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; }
.logo {
  display: inline-grid; place-items: center; width: 32px; height: 32px; border-radius: 10px; color: #fff; font-weight: 700;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
}
.logo-sm { width: 22px; height: 22px; border-radius: 7px; font-size: 12px; margin-right: 8px; vertical-align: middle; }
.nav nav { display: flex; gap: 20px; margin-left: 12px; color: var(--muted); font-size: 15px; }
.nav nav a:hover { color: var(--text); }
.pill {
  margin-left: auto; display: inline-flex; align-items: center; gap: 8px; padding: 6px 12px; border-radius: 999px;
  font-size: 13px; border: 1px solid var(--line); background: var(--surface); white-space: nowrap;
}
.pill-warn { color: var(--warn); }
.dot { width: 8px; height: 8px; border-radius: 50%; background: currentColor; display: inline-block; }
.pill .dot { animation: pulse 1.8s ease-in-out infinite; }
@keyframes pulse { 50% { opacity: .35; } }

main { max-width: 1120px; margin: 0 auto; padding: 0 20px; }
.eyebrow { margin: 0 0 10px; font-size: 12px; letter-spacing: .14em; color: var(--accent-2); font-weight: 600; }
.muted { color: var(--muted); }

.hero { text-align: center; padding: 64px 0 40px; }
.hero h1 { font-size: clamp(34px, 6vw, 60px); line-height: 1.15; margin: 0 0 18px; letter-spacing: -.02em; }
.grad { background: linear-gradient(90deg, var(--accent), var(--accent-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.lead { max-width: 640px; margin: 0 auto 40px; color: var(--muted); font-size: 17px; }

.chat {
  max-width: 760px; margin: 0 auto; text-align: left; background: var(--surface); border: 1px solid var(--line);
  border-radius: 20px; box-shadow: 0 30px 80px -30px rgba(0,0,0,.55); overflow: hidden;
}
.chat-head { display: flex; justify-content: space-between; align-items: center; padding: 14px 20px; border-bottom: 1px solid var(--line); font-size: 14px; }
.chat-title { font-weight: 600; }
.chat-model { color: var(--muted); }
.chat-body { padding: 22px 20px 6px; display: grid; gap: 18px; }
.msg p { margin: 0 0 8px; }
.msg.user { justify-self: end; max-width: 85%; background: var(--surface-2); border: 1px solid var(--line); padding: 10px 16px; border-radius: 16px 16px 4px 16px; }
.msg.user p { margin: 0; }
.msg.ai { display: grid; grid-template-columns: 32px 1fr; gap: 12px; }
.avatar { width: 32px; height: 32px; border-radius: 10px; display: grid; place-items: center; color: #fff; font-weight: 700; font-size: 14px; background: linear-gradient(135deg, var(--accent), var(--accent-2)); }
.route { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; margin-bottom: 10px; font-size: 12px; }
.arrow { color: var(--muted); }
.chip { padding: 3px 9px; border-radius: 999px; border: 1px solid currentColor; background: color-mix(in srgb, currentColor 10%, transparent); }
.chip-exec { color: var(--exec); } .chip-math { color: var(--math); } .chip-code { color: var(--code); } .chip-lang { color: var(--lang); }
.sample-note { font-size: 12px; color: var(--muted); }
.composer { display: flex; gap: 10px; align-items: flex-end; margin: 12px 16px 6px; padding: 10px 10px 10px 16px; border: 1px solid var(--line); border-radius: 14px; background: var(--surface-2); }
.composer textarea { flex: 1; resize: none; border: 0; background: transparent; color: var(--text); font: inherit; outline: none; padding: 6px 0; }
.composer textarea::placeholder { color: var(--muted); }
.composer button { width: 36px; height: 36px; border-radius: 10px; border: 0; font-size: 18px; color: var(--muted); background: var(--line); cursor: not-allowed; }
.composer-hint { margin: 0 16px 14px; font-size: 12px; color: var(--muted); text-align: center; }

.section { padding: 72px 0 8px; }
.section-head { text-align: center; margin-bottom: 36px; }
.section-head h2, .status-card h2 { font-size: clamp(26px, 4vw, 36px); margin: 0 0 10px; letter-spacing: -.01em; }

.models { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; }
.model { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; transition: transform .2s, border-color .2s; }
.model:hover { transform: translateY(-3px); border-color: color-mix(in srgb, var(--accent) 50%, var(--line)); }
.model.featured { grid-column: 1 / -1; background: linear-gradient(135deg, color-mix(in srgb, var(--accent) 14%, var(--surface)), var(--surface) 60%); }
.model-top { display: flex; justify-content: space-between; align-items: center; margin-bottom: 14px; }
.role { font-size: 12px; font-weight: 600; padding: 4px 10px; border-radius: 999px; background: color-mix(in srgb, currentColor 14%, transparent); }
.role-exec { color: var(--exec); } .role-lang { color: var(--lang); } .role-math { color: var(--math); } .role-sci { color: var(--sci); } .role-code { color: var(--code); }
.size { font-size: 13px; color: var(--muted); font-variant-numeric: tabular-nums; }
.model h3 { margin: 0 0 8px; font-size: 18px; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; word-break: break-all; }
.model p { margin: 0 0 16px; color: var(--muted); font-size: 15px; }
.model dl { margin: 0; display: flex; gap: 24px; flex-wrap: wrap; font-size: 13px; }
.model dt { color: var(--muted); }
.model dd { margin: 0; font-weight: 600; }
.fine { text-align: center; color: var(--muted); font-size: 13px; margin-top: 20px; }

.steps { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; }
.steps li { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.steps .n { display: inline-grid; place-items: center; width: 30px; height: 30px; border-radius: 50%; font-weight: 700; font-size: 14px; color: #fff; background: linear-gradient(135deg, var(--accent), var(--accent-2)); }
.steps h3 { margin: 14px 0 6px; font-size: 18px; }
.steps p { margin: 0; color: var(--muted); font-size: 15px; }

.status-card { display: grid; grid-template-columns: 1.6fr 1fr; gap: 32px; align-items: center; background: var(--surface); border: 1px solid var(--line); border-radius: 20px; padding: 32px; }
.status-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 12px; }
.status-list li { display: flex; align-items: center; gap: 10px; padding: 12px 14px; border-radius: 12px; background: var(--surface-2); font-size: 15px; }
.dot-warn { color: var(--warn); } .dot-off { color: var(--muted); }

.footer { max-width: 1120px; margin: 80px auto 0; padding: 28px 20px 40px; border-top: 1px solid var(--line); display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; font-size: 14px; }

@media (max-width: 720px) {
  .nav { gap: 12px; padding: 14px 16px; }
  .nav nav { display: none; }
  main { padding: 0 16px; }
  .hero { padding-top: 40px; }
  .status-card { grid-template-columns: 1fr; padding: 24px; }
  .msg.user { max-width: 100%; }
}

.composer textarea { max-height: 200px; }
.composer:focus-within { border-color: color-mix(in srgb, var(--accent) 60%, var(--line)); }
.msg.notice {
  justify-self: center; max-width: 100%; font-size: 14px; color: var(--warn); text-align: center;
  padding: 10px 16px; border-radius: 12px; border: 1px solid color-mix(in srgb, var(--warn) 45%, transparent);
  background: color-mix(in srgb, var(--warn) 10%, transparent);
}
.shake { animation: shake .35s ease; }
@keyframes shake { 25% { transform: translateX(-4px); } 75% { transform: translateX(4px); } }
.pill-ok { color: var(--lang); }
.composer button:not(:disabled) { color: #fff; background: var(--accent); cursor: pointer; }
.composer button:not(:disabled):hover { filter: brightness(1.1); }
.msg.ai-plain { max-width: 85%; background: var(--surface-2); border: 1px solid var(--line); padding: 10px 16px; border-radius: 16px 16px 16px 4px; white-space: pre-wrap; }
.msg.ai-plain p, .msg.user p { white-space: pre-wrap; }