:root {
  --brand: #174d3b;
  --brand-2: #1f7a57;
  --cream: #faf7ef;
  --text: #13261f;
  --muted: #55665e;
  --bg: #f6f3ea;
  --card: #fffdf8;
  --line: #e4ded0;
  --shadow: 0 1px 2px rgba(19, 38, 31, .04), 0 12px 32px rgba(19, 38, 31, .07);
  --kbd-bg: #f1ede2;
  --c-overlay: #1f7a57;
  --c-flow: #2563eb;
  --c-write: #c2410c;
  --c-read: #7c3aed;
  --c-ref: #64748b;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --brand: #7fd1a8; --brand-2: #7fd1a8; --text: #e9efe9; --muted: #a8b5ae; --bg: #0f1412; --card: #161d1a; --line: #27322d;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 12px 32px rgba(0, 0, 0, .35); --kbd-bg: #222b27;
    --c-overlay: #6fcf9f; --c-flow: #7aa7ff; --c-write: #fb923c; --c-read: #b794f6; --c-ref: #94a3b8;
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 90px; }
body { margin: 0; background: var(--bg); color: var(--text); font: 16.5px/1.65 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, "Noto Sans TC", sans-serif; -webkit-font-smoothing: antialiased; }
a { color: var(--brand-2); }
code { font: .88em ui-monospace, SFMono-Regular, Menlo, monospace; background: var(--kbd-bg); padding: 1px 6px; border-radius: 5px; }
kbd { display: inline-block; padding: 0 8px; margin: 0 1px; font: 600 .82em/1.7 ui-monospace, SFMono-Regular, Menlo, monospace; color: var(--text); background: var(--kbd-bg);
  border: 1px solid var(--line); border-radius: 6px; box-shadow: 0 1.5px 0 var(--line); white-space: nowrap; }

/* ---------- top bar ---------- */
.top { position: sticky; top: 0; z-index: 30; display: flex; align-items: center; gap: 14px; padding: 12px 28px; background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(1.4) blur(14px); border-bottom: 1px solid color-mix(in srgb, var(--line) 70%, transparent); }
.top .mark { display: flex; align-items: center; gap: 10px; font-weight: 750; font-size: 18px; color: var(--text); text-decoration: none; letter-spacing: -.2px; }
.top .mark img { width: 30px; height: 30px; border-radius: 8px; }
.top .sp { flex: 1; }
.top .lnk { color: var(--muted); text-decoration: none; font-size: 14.5px; font-weight: 500; }
.top .lnk:hover { color: var(--text); }
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 10px 18px; border-radius: 999px; font-weight: 650; font-size: 15px; text-decoration: none; border: 0; cursor: pointer; }
.btn.solid { background: #174d3b; color: #faf7ef; }
.btn.solid:hover { background: #12402f; }
.btn.ghost { background: transparent; color: var(--text); box-shadow: inset 0 0 0 1px var(--line); }
.btn.ghost:hover { background: var(--card); }
.btn.sm { padding: 7px 14px; font-size: 14px; }

/* ---------- hero ---------- */
.hero { text-align: center; padding: 72px 24px 40px; max-width: 1100px; margin: 0 auto; }
.hero .logo { width: 92px; height: 92px; border-radius: 24px; box-shadow: 0 18px 40px rgba(23, 77, 59, .25); animation: rise .7s ease-out both; }
.eyebrow { display: inline-block; margin-top: 22px; padding: 5px 14px; border-radius: 999px; font-size: 13px; font-weight: 650; letter-spacing: .5px; color: var(--brand-2); background: color-mix(in srgb, var(--brand-2) 12%, transparent); }
.hero h1 { font-size: clamp(44px, 7vw, 84px); line-height: 1.02; letter-spacing: -3px; margin: 18px 0 14px; font-weight: 800;
  background: linear-gradient(100deg, #174d3b, #2f9b6e 35%, #c2410c 55%, #2563eb 75%, #174d3b); background-size: 300% 100%; -webkit-background-clip: text; background-clip: text; color: transparent;
  animation: flow 9s ease-in-out infinite, rise .7s .1s ease-out both; }
@media (prefers-color-scheme: dark) { .hero h1 { background-image: linear-gradient(100deg, #7fd1a8, #b8f0d0 35%, #fdba74 55%, #93b4ff 75%, #7fd1a8); } }
.hero p.lead { font-size: 21px; color: var(--muted); max-width: 720px; margin: 0 auto 28px; animation: rise .7s .2s ease-out both; }
.hero .ctas { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; animation: rise .7s .3s ease-out both; }
@keyframes flow { 0%, 100% { background-position: 0% 50%; } 50% { background-position: 100% 50%; } }
@keyframes rise { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: none; } }

.film { max-width: 1180px; margin: 10px auto 0; padding: 0 24px; }
.film .vid { position: relative; border-radius: 20px; overflow: hidden; box-shadow: 0 40px 80px rgba(19, 38, 31, .22), 0 0 0 1px var(--line); background: #000; aspect-ratio: 16 / 9; }
.film video { width: 100%; height: 100%; display: block; }
.film .note { text-align: center; color: var(--muted); font-size: 14px; margin-top: 14px; }
.stats { display: flex; justify-content: center; gap: 44px; flex-wrap: wrap; margin: 46px auto 0; color: var(--muted); font-size: 14.5px; }
.stats b { display: block; font-size: 30px; color: var(--text); letter-spacing: -1px; }

/* ---------- layout ---------- */
.layout { display: grid; grid-template-columns: 250px minmax(0, 1fr); gap: 48px; max-width: 1320px; margin: 70px auto 0; padding: 0 28px 80px; }
.nav { position: sticky; top: 84px; align-self: start; max-height: calc(100vh - 100px); overflow: auto; padding: 4px 6px 20px 0; font-size: 14px; }
.nav .grp { margin-bottom: 18px; }
.nav .gt { display: block; font-size: 11.5px; font-weight: 750; letter-spacing: 1.2px; text-transform: uppercase; margin: 0 0 6px 12px; color: var(--g); }
.nav a { display: block; padding: 5px 12px; border-radius: 8px; color: var(--muted); text-decoration: none; border-left: 2.5px solid transparent; }
.nav a:hover { color: var(--text); background: color-mix(in srgb, var(--g) 8%, transparent); }
.nav a.on { color: var(--text); font-weight: 600; border-left-color: var(--g); background: color-mix(in srgb, var(--g) 10%, transparent); border-radius: 0 8px 8px 0; }
.g-overlay { --g: var(--c-overlay); } .g-flow { --g: var(--c-flow); } .g-write { --g: var(--c-write); } .g-read { --g: var(--c-read); } .g-ref { --g: var(--c-ref); }

.part { margin: 0 0 26px; padding-top: 18px; }
.part:not(:first-child) { margin-top: 70px; }
.part .k { font: 650 13px ui-monospace, SFMono-Regular, Menlo, monospace; letter-spacing: 2px; text-transform: uppercase; color: var(--g); }
.part h2 { font-size: 46px; letter-spacing: -1.8px; line-height: 1.05; margin: 8px 0 8px; color: var(--g); }
.part p { margin: 0; color: var(--muted); font-size: 18.5px; max-width: 760px; }

/* ---------- feature cards ---------- */
.sec { position: relative; background: var(--card); border: 1px solid var(--line); border-radius: 22px; padding: 30px 32px 28px; margin: 0 0 28px; box-shadow: var(--shadow); overflow: hidden; }
.sec::before { content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 5px; background: var(--g); }
.sec .hd { display: flex; align-items: baseline; gap: 14px; flex-wrap: wrap; }
.sec h3 { font-size: 28px; letter-spacing: -.8px; margin: 0; line-height: 1.2; }
.sec .num { font: 600 13px ui-monospace, Menlo, monospace; color: var(--g); }
.sec .chips { margin-left: auto; display: flex; gap: 6px; flex-wrap: wrap; }
.sec .chip { font-size: 12px; font-weight: 650; padding: 3px 10px; border-radius: 999px; color: var(--g); background: color-mix(in srgb, var(--g) 12%, transparent); }
.sec .desc { font-size: 17px; margin: 10px 0 20px; color: var(--muted); line-height: 1.8; }
.sec .desc b { color: var(--text); }

.demo-wrap { position: relative; border-radius: 16px; padding: 10px; background: linear-gradient(135deg, color-mix(in srgb, var(--g) 22%, transparent), color-mix(in srgb, var(--g) 4%, transparent)); }
.demo-wrap .demo { box-shadow: 0 18px 40px rgba(19, 38, 31, .18); }
.ctl { display: flex; align-items: center; gap: 12px; margin-top: 10px; padding: 0 4px; }
.ctl button { width: 34px; height: 34px; border-radius: 50%; border: 0; display: grid; place-items: center; cursor: pointer; background: var(--card); color: var(--text); box-shadow: 0 0 0 1px var(--line); }
.ctl button:hover { background: var(--bg); }
.ctl button svg { width: 15px; height: 15px; }
.ctl .prog { flex: 1; height: 4px; border-radius: 2px; background: color-mix(in srgb, var(--g) 15%, transparent); cursor: pointer; position: relative; }
.ctl .prog i { position: absolute; left: 0; top: 0; bottom: 0; border-radius: 2px; background: var(--g); }
.ctl .lbl { font-size: 12.5px; color: var(--muted); }

.more { margin: 22px 0 0; }
.more summary { cursor: pointer; font-weight: 650; font-size: 15px; color: var(--g); list-style: none; display: inline-flex; align-items: center; gap: 6px; }
.more summary::-webkit-details-marker { display: none; }
.more summary::before { content: "›"; display: inline-block; transition: transform .2s; font-size: 20px; line-height: 1; }
.more[open] summary::before { transform: rotate(90deg); }
.more ul { margin: 12px 0 0; padding-left: 20px; color: var(--muted); font-size: 15.5px; }
.more li { margin: 0 0 8px; }
.more li::marker { color: var(--g); }
li:has(kbd) { line-height: 1.9; }

/* ---------- reference ---------- */
table { width: 100%; border-collapse: collapse; font-size: 15.5px; }
th, td { text-align: left; padding: 12px 14px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { font-size: 12.5px; text-transform: uppercase; letter-spacing: .8px; color: var(--muted); font-weight: 650; }
tr:last-child td { border-bottom: 0; }
.shot { display: block; width: 100%; border-radius: 14px; box-shadow: 0 18px 40px rgba(19, 38, 31, .16), 0 0 0 1px var(--line); }
.grid2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 14px; margin-top: 18px; }
.tile { border: 1px solid var(--line); border-radius: 14px; padding: 16px 18px; background: var(--bg); }
.tile b { display: block; margin-bottom: 4px; }
.tile span { color: var(--muted); font-size: 14.5px; }
.callout { margin-top: 18px; padding: 14px 18px; border-radius: 12px; background: color-mix(in srgb, #d97706 10%, transparent); border: 1px solid color-mix(in srgb, #d97706 30%, transparent); font-size: 15px; }

.cta-end { text-align: center; padding: 64px 24px; margin: 30px 0 0; border-radius: 28px; background: #174d3b; color: #faf7ef; }
.cta-end h2 { font-size: 44px; letter-spacing: -1.6px; margin: 14px 0 8px; }
.cta-end p { color: #cfe5d8; margin: 0 0 26px; font-size: 18px; }
.cta-end .btn.solid { background: #faf7ef; color: #174d3b; }
.cta-end .btn.ghost { color: #faf7ef; box-shadow: inset 0 0 0 1px rgba(250, 247, 239, .35); }
.cta-end .btn.ghost:hover { background: rgba(250, 247, 239, .08); }
footer { text-align: center; color: var(--muted); font-size: 13.5px; padding: 0 24px 50px; }

.jump { position: fixed; right: 22px; bottom: 22px; display: flex; flex-direction: column; gap: 8px; z-index: 20; }
.jump button { width: 40px; height: 40px; border-radius: 50%; border: 0; cursor: pointer; background: var(--card); color: var(--text); box-shadow: var(--shadow), 0 0 0 1px var(--line); font-size: 16px; }

@media (max-width: 1000px) {
  .layout { grid-template-columns: 1fr; gap: 0; margin-top: 40px; }
  .nav { display: none; }
  .top .lnk { display: none; }
  .sec { padding: 22px 18px; }
  .part h2 { font-size: 36px; }
}
@media (prefers-reduced-motion: reduce) { * { animation: none !important; } html { scroll-behavior: auto; } }
.shotbox { position: relative; max-height: 560px; overflow: auto; border-radius: 14px; background: #fff; box-shadow: 0 18px 40px rgba(19, 38, 31, .16), 0 0 0 1px var(--line); }
.shotbox img { display: block; width: 100%; }
.shotbox .hint { position: sticky; bottom: 12px; left: 0; display: table; margin: -44px auto 12px; padding: 6px 14px; border-radius: 999px; background: rgba(19, 38, 31, .82); color: #fff; font-size: 13px; font-weight: 600; }