:root {
  --accent: #3b6cf6;
  --accent-ink: #2550d4;
  --accent-soft: #eef2fe;
  --ink: #1d1d1f;
  --ink-2: #48484d;
  --ink-3: #6e6e73;
  --line: #e5e5ea;
  --bg: #ffffff;
  --bg-2: #f6f7f9;
  --warm: #f59e0b;
  --radius: 14px;
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  color-scheme: light;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body { margin: 0; font-family: var(--font); color: var(--ink); background: var(--bg); line-height: 1.7; font-size: 16px; }
img, video { max-width: 100%; height: auto; display: block; }
a { color: var(--accent-ink); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3 { line-height: 1.3; letter-spacing: -0.01em; margin: 0 0 .5em; }
h1 { font-size: clamp(30px, 5.2vw, 50px); font-weight: 800; }
h2 { font-size: clamp(24px, 3.4vw, 34px); font-weight: 750; }
h3 { font-size: 19px; font-weight: 700; }
p { margin: 0 0 1em; }
.wrap { max-width: 1080px; margin: 0 auto; padding: 0 20px; }
.narrow { max-width: 760px; }
.muted { color: var(--ink-3); }
.small { font-size: 14px; }

/* 顶栏 */
.nav { position: sticky; top: 0; z-index: 10; background: rgba(255,255,255,.88); backdrop-filter: saturate(180%) blur(16px); -webkit-backdrop-filter: saturate(180%) blur(16px); border-bottom: 1px solid var(--line); }
.nav .wrap { display: flex; align-items: center; gap: 22px; height: 58px; }
.brand { display: flex; align-items: center; gap: 9px; font-weight: 750; font-size: 18px; color: var(--ink); }
.brand img { width: 28px; height: 28px; border-radius: 7px; }
.brand:hover { text-decoration: none; }
.nav .links { display: flex; gap: 20px; margin-left: auto; font-size: 15px; }
.nav .links a { color: var(--ink-2); }
.nav .cta { padding: 6px 14px; border-radius: 999px; background: var(--accent); color: #fff; font-size: 14px; font-weight: 600; }
.nav .cta:hover { background: var(--accent-ink); text-decoration: none; }
@media (max-width: 720px) { .nav .links { display: none; } .nav .cta { margin-left: auto; } }

/* 按钮 */
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 13px 22px; border-radius: 12px; font-weight: 650; font-size: 16px; border: 1px solid transparent; cursor: pointer; }
.btn.primary { background: var(--accent); color: #fff; box-shadow: 0 6px 18px rgba(59,108,246,.28); }
.btn.primary:hover { background: var(--accent-ink); text-decoration: none; }
.btn.ghost { background: #fff; color: var(--ink); border-color: var(--line); }
.btn.ghost:hover { border-color: #c9c9cf; text-decoration: none; }

/* 首屏 */
.hero { padding: 64px 0 40px; background: radial-gradient(900px 420px at 85% -10%, #e6edff 0%, transparent 65%), radial-gradient(700px 380px at -10% 10%, #fff3dd 0%, transparent 60%); }
.hero .grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 48px; align-items: center; }
.hero .lead { font-size: 19px; color: var(--ink-2); max-width: 34em; }
.hero .actions { display: flex; flex-wrap: wrap; gap: 12px; margin: 26px 0 12px; }
.hero .meta { font-size: 14px; color: var(--ink-3); }
.hero .shot { border-radius: 16px; box-shadow: 0 30px 60px -20px rgba(30,40,80,.35), 0 0 0 1px rgba(0,0,0,.04); }
.kbd { display: inline-block; padding: 0 7px; border: 1px solid #d2d2d7; border-bottom-width: 2px; border-radius: 6px; font-family: var(--font); font-size: .9em; background: #fff; line-height: 1.6; }
@media (max-width: 860px) { .hero { padding-top: 40px; } .hero .grid { grid-template-columns: 1fr; gap: 32px; } }

/* 区块 */
section { padding: 72px 0; }
section.alt { background: var(--bg-2); }
.sec-head { max-width: 640px; margin-bottom: 36px; }
.sec-head p { color: var(--ink-2); font-size: 17px; }
.eyebrow { font-size: 14px; font-weight: 650; color: var(--accent-ink); letter-spacing: .02em; margin-bottom: 6px; }

/* 三步 */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; counter-reset: step; }
.step { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; }
.step::before { counter-increment: step; content: counter(step); display: inline-grid; place-items: center; width: 30px; height: 30px; border-radius: 50%; background: var(--accent-soft); color: var(--accent-ink); font-weight: 750; margin-bottom: 12px; }
.step img { margin-top: 14px; border-radius: 10px; border: 1px solid var(--line); }
@media (max-width: 860px) { .steps { grid-template-columns: 1fr; } }

/* 功能 */
.feature { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; margin-bottom: 72px; }
.feature:last-child { margin-bottom: 0; }
.feature.flip .text { order: 2; }
.feature .text p { color: var(--ink-2); }
.feature ul { padding-left: 1.1em; margin: 0; color: var(--ink-2); }
.feature li { margin-bottom: 6px; }
.feature img { border-radius: 14px; box-shadow: 0 20px 44px -18px rgba(30,40,80,.3), 0 0 0 1px rgba(0,0,0,.05); }
@media (max-width: 860px) { .feature { grid-template-columns: 1fr; gap: 24px; } .feature.flip .text { order: 0; } }

.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; }
.card h3 { font-size: 17px; margin-bottom: 6px; }
.card p { color: var(--ink-2); font-size: 15px; margin: 0; }
@media (max-width: 860px) { .cards { grid-template-columns: 1fr; } }

/* 表格 */
table { width: 100%; border-collapse: collapse; font-size: 15px; }
th, td { text-align: left; padding: 11px 12px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { color: var(--ink-3); font-weight: 600; font-size: 14px; }
.table-wrap { overflow-x: auto; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); }

/* 下载 */
.download-box { background: #fff; border: 1px solid var(--line); border-radius: 18px; padding: 28px; display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 32px; }
.download-box > div, .feature > *, .hero .grid > * { min-width: 0; }
.cmd { display: flex; align-items: center; gap: 10px; background: #111318; color: #e7e9ee; border-radius: 10px; padding: 12px 14px; font-family: var(--mono); font-size: 13.5px; overflow: hidden; }
.cmd code { white-space: nowrap; flex: 1; min-width: 0; overflow-x: auto; }
.copy { flex: none; background: #2a2e38; color: #fff; border: 0; border-radius: 7px; padding: 6px 11px; font-size: 13px; cursor: pointer; font-family: var(--font); }
.copy:hover { background: #3a3f4c; }
ol.howto { padding-left: 1.2em; color: var(--ink-2); }
ol.howto li { margin-bottom: 8px; }
.note { background: #fff8eb; border: 1px solid #fde3b0; border-radius: 12px; padding: 14px 16px; color: #6b4a00; font-size: 15px; }
@media (max-width: 860px) { .download-box { grid-template-columns: minmax(0, 1fr); padding: 20px; } }

/* 常见问题 */
details { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 0 18px; margin-bottom: 10px; }
summary { cursor: pointer; padding: 15px 0; font-weight: 650; list-style: none; position: relative; padding-right: 26px; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; position: absolute; right: 0; top: 12px; font-size: 22px; color: var(--ink-3); font-weight: 400; }
details[open] summary::after { content: "–"; }
details > div { padding: 0 0 16px; color: var(--ink-2); }

/* 指南列表 */
.guide-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.guide-list a { display: block; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; color: var(--ink); }
.guide-list a:hover { border-color: var(--accent); text-decoration: none; }
.guide-list b { display: block; margin-bottom: 6px; font-size: 17px; }
.guide-list span { color: var(--ink-3); font-size: 14.5px; }
@media (max-width: 860px) { .guide-list { grid-template-columns: 1fr; } }

/* 文章 */
.article { padding: 48px 0 72px; }
.article h1 { font-size: clamp(28px, 4.4vw, 40px); }
.article h2 { font-size: 24px; margin-top: 2em; }
.article h3 { margin-top: 1.6em; }
.article p, .article li { color: #2c2c30; font-size: 17px; }
.article figure { margin: 1.6em 0; }
.article figure img { border-radius: 12px; border: 1px solid var(--line); }
.article figcaption { font-size: 14px; color: var(--ink-3); margin-top: 8px; }
.crumbs { font-size: 14px; color: var(--ink-3); margin-bottom: 18px; }
.crumbs a { color: var(--ink-3); }
.summary { background: var(--accent-soft); border-radius: 12px; padding: 16px 18px; color: #22305a; margin-bottom: 1.6em; }
.cta-box { margin-top: 2.4em; padding: 24px; border: 1px solid var(--line); border-radius: 16px; background: var(--bg-2); }

/* 页脚 */
footer { border-top: 1px solid var(--line); padding: 36px 0 48px; font-size: 14px; color: var(--ink-3); }
footer .cols { display: flex; flex-wrap: wrap; gap: 28px; justify-content: space-between; }
footer a { color: var(--ink-2); }
footer .links { display: flex; flex-wrap: wrap; gap: 16px; }