:root {
  --bg: #fbfbfd;
  --bg-alt: #f2f3f7;
  --card: #ffffff;
  --text: #1d1d1f;
  --sub: #6e6e73;
  --faint: #86868b;
  --line: rgba(0, 0, 0, 0.08);
  --accent: #0071e3;
  --accent-ink: #ffffff;
  --green: #1f9d4c;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 12px 40px rgba(0, 0, 0, 0.08);
  --radius: 22px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #000000;
    --bg-alt: #0d0d0f;
    --card: #1c1c1e;
    --text: #f5f5f7;
    --sub: #a1a1a6;
    --faint: #86868b;
    --line: rgba(255, 255, 255, 0.1);
    --accent: #2997ff;
    --green: #30d158;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 16px 48px rgba(0, 0, 0, 0.5);
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.wrap { max-width: 1080px; margin: 0 auto; padding: 0 22px; }

/* Nav */
.nav {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--line);
}
.nav .wrap { display: flex; align-items: center; gap: 24px; height: 52px; }
.brand { display: flex; align-items: center; gap: 9px; color: var(--text); font-weight: 600; font-size: 17px; }
.brand:hover { text-decoration: none; }
.brand img { width: 26px; height: 26px; border-radius: 6px; }
.nav .links { display: flex; gap: 22px; margin-left: auto; font-size: 14px; }
.nav .links a { color: var(--sub); }
.nav .links a:hover { color: var(--text); text-decoration: none; }
@media (max-width: 640px) { .nav .links { display: none; } .nav .btn { margin-left: auto; } }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  padding: 11px 22px; border-radius: 980px; border: 0;
  background: var(--accent); color: var(--accent-ink);
  font: inherit; font-size: 16px; font-weight: 500; cursor: pointer; white-space: nowrap;
}
.btn:hover { text-decoration: none; filter: brightness(1.08); }
.btn.small { padding: 6px 14px; font-size: 14px; }
.btn.ghost { background: transparent; color: var(--accent); box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--accent) 45%, transparent); }
.btn[aria-disabled="true"] { background: color-mix(in srgb, var(--text) 8%, transparent); color: var(--sub); cursor: default; filter: none; box-shadow: none; }

/* Hero */
.hero { text-align: center; padding: 88px 0 40px; }
.eyebrow { color: var(--accent); font-weight: 600; font-size: 15px; letter-spacing: 0.02em; margin: 0 0 14px; }
.hero h1 { font-size: clamp(40px, 7vw, 72px); line-height: 1.07; letter-spacing: -0.015em; margin: 0 0 20px; font-weight: 700; }
.hero p.lead { font-size: clamp(18px, 2.4vw, 22px); color: var(--sub); max-width: 680px; margin: 0 auto 32px; }
.hero .ctas { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.hero .meta { margin-top: 16px; font-size: 13px; color: var(--faint); }
.shot { margin: 56px auto 0; width: 100%; max-width: min(1040px, 100%); filter: drop-shadow(0 30px 60px rgba(0, 0, 0, 0.18)); }
@media (prefers-color-scheme: dark) { .shot { filter: drop-shadow(0 30px 70px rgba(0, 0, 0, 0.7)); } }

/* Sections */
section { padding: 96px 0; }
section.alt { background: var(--bg-alt); }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 56px; }
.section-head h2 { font-size: clamp(30px, 4.6vw, 48px); line-height: 1.1; letter-spacing: -0.01em; margin: 0 0 14px; }
.section-head p { color: var(--sub); font-size: 19px; margin: 0; }

.grid { display: grid; gap: 20px; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.card { background: var(--card); border-radius: var(--radius); padding: 30px; box-shadow: var(--shadow); }
.card h3 { font-size: 21px; margin: 16px 0 8px; letter-spacing: -0.005em; }
.card p { color: var(--sub); margin: 0; font-size: 16px; }
.icon { width: 44px; height: 44px; border-radius: 12px; display: grid; place-items: center; color: #fff; }
.icon svg { width: 24px; height: 24px; }
.i-blue { background: linear-gradient(160deg, #4f8ef7, #2563eb); }
.i-purple { background: linear-gradient(160deg, #a78bfa, #7c3aed); }
.i-teal { background: linear-gradient(160deg, #2dd4bf, #0f9488); }
.i-orange { background: linear-gradient(160deg, #fb923c, #ea580c); }
.i-green { background: linear-gradient(160deg, #4ade80, #16a34a); }
.i-pink { background: linear-gradient(160deg, #f472b6, #db2777); }

/* Protocol chips */
.chips { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; }
.chip { display: inline-flex; align-items: center; gap: 8px; padding: 8px 15px; border-radius: 980px; background: var(--card); box-shadow: var(--shadow); font-size: 15px; font-weight: 500; }
.chip i { width: 9px; height: 9px; border-radius: 50%; display: inline-block; }

/* Split feature */
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
@media (max-width: 860px) { .split { grid-template-columns: 1fr; } }
.split h2 { font-size: clamp(30px, 4.2vw, 44px); line-height: 1.12; margin: 0 0 16px; letter-spacing: -0.01em; }
.split p { color: var(--sub); font-size: 18px; }
.split ul { padding-left: 20px; color: var(--sub); }
.split li { margin: 6px 0; }
.region-demo { display: grid; gap: 14px; }
.region-row { display: flex; align-items: center; gap: 14px; background: var(--card); border-radius: 18px; padding: 16px 18px; box-shadow: var(--shadow); }
.region-row .flag { font-size: 30px; line-height: 1; }
.region-row b { display: block; font-size: 16px; }
.region-row span { color: var(--sub); font-size: 14px; }
.region-row .tag { margin-left: auto; font: 12px ui-monospace, Menlo, monospace; color: var(--sub); background: var(--bg-alt); padding: 4px 9px; border-radius: 8px; }

/* Stats */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; text-align: center; }
@media (max-width: 760px) { .stats { grid-template-columns: repeat(2, 1fr); } }
.stat b { display: block; font-size: clamp(34px, 5vw, 52px); letter-spacing: -0.02em; line-height: 1.1; }
.stat span { color: var(--sub); font-size: 15px; }

/* Pricing */
.plans { display: grid; gap: 18px; grid-template-columns: repeat(4, 1fr); }
@media (max-width: 960px) { .plans { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 520px) { .plans { grid-template-columns: 1fr; } }
.plan { background: var(--card); border-radius: var(--radius); padding: 28px 24px; box-shadow: var(--shadow); display: flex; flex-direction: column; position: relative; }
.plan.featured { box-shadow: 0 0 0 2px var(--accent), var(--shadow); }
.plan .badge { position: absolute; top: -12px; left: 50%; transform: translateX(-50%); background: var(--accent); color: #fff; font-size: 12px; font-weight: 600; padding: 3px 12px; border-radius: 980px; }
.plan h3 { margin: 0; font-size: 19px; }
.plan .seats { color: var(--sub); font-size: 15px; margin: 2px 0 18px; }
.plan .price { font-size: 38px; font-weight: 700; letter-spacing: -0.02em; line-height: 1.1; min-height: 46px; }
.plan .price small { font-size: 15px; font-weight: 500; color: var(--sub); letter-spacing: 0; }
.plan .price.tbd { font-size: 20px; color: var(--sub); font-weight: 600; padding-top: 12px; }
.plan ul { list-style: none; padding: 0; margin: 18px 0 24px; color: var(--sub); font-size: 15px; flex: 1; }
.plan li { padding: 5px 0 5px 22px; position: relative; }
.plan li::before { content: "✓"; position: absolute; left: 0; color: var(--green); font-weight: 700; }
.plan .btn { width: 100%; }
.fineprint { text-align: center; color: var(--faint); font-size: 14px; margin-top: 28px; }

/* FAQ */
.faq { max-width: 780px; margin: 0 auto; }
.faq details { border-bottom: 1px solid var(--line); padding: 18px 0; }
.faq summary { cursor: pointer; font-weight: 600; font-size: 18px; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--faint); font-weight: 400; font-size: 24px; line-height: 1; transition: transform 0.2s; }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details p { color: var(--sub); margin: 10px 0 0; }

/* Footer */
footer { border-top: 1px solid var(--line); padding: 34px 0 48px; color: var(--faint); font-size: 13px; }
footer .wrap { display: flex; flex-wrap: wrap; gap: 14px 26px; align-items: center; }
footer nav { display: flex; flex-wrap: wrap; gap: 8px 22px; margin-left: auto; }
footer a { color: var(--sub); }

/* Document pages (legal, guide) */
.doc { max-width: 760px; margin: 0 auto; padding: 64px 22px 96px; }
.doc h1 { font-size: clamp(32px, 5vw, 44px); line-height: 1.15; margin: 0 0 8px; letter-spacing: -0.01em; }
.doc .updated { color: var(--faint); font-size: 14px; margin: 0 0 40px; }
.doc h2 { font-size: 23px; margin: 40px 0 10px; }
.doc h3 { font-size: 18px; margin: 26px 0 6px; }
.doc p, .doc li { color: var(--sub); }
.doc li { margin: 6px 0; }
.doc table { width: 100%; border-collapse: collapse; font-size: 15px; margin: 12px 0; }
.doc th, .doc td { text-align: left; padding: 10px 8px; border-bottom: 1px solid var(--line); vertical-align: top; }
.doc th { color: var(--text); font-weight: 600; }
.doc td { color: var(--sub); }
.doc code { font: 14px ui-monospace, Menlo, monospace; background: var(--bg-alt); padding: 2px 6px; border-radius: 6px; }
.note { background: var(--bg-alt); border-radius: 14px; padding: 14px 18px; color: var(--sub); font-size: 15px; }