/* ==========================================================================
   ggbv-whatsapp.com.cn — 全站样式（零外部依赖，无 CDN / 无网络字体）
   ========================================================================== */

:root {
  --bg: #f5f8f6;
  --bg-soft: #eef4f1;
  --surface: #ffffff;
  --surface-2: #fbfdfc;
  --ink: #0f2019;
  --ink-2: #223a31;
  --muted: #5d7268;
  --line: #e2ebe6;
  --line-strong: #cfdcd5;
  --brand: #17a34a;
  --brand-2: #25d366;
  --brand-ink: #0a7a39;
  --brand-soft: #e8f8ee;
  --teal: #0d9488;
  --amber: #b45309;
  --shadow-sm: 0 1px 2px rgba(15, 32, 25, .06), 0 1px 3px rgba(15, 32, 25, .04);
  --shadow: 0 8px 24px -12px rgba(15, 32, 25, .18), 0 2px 6px rgba(15, 32, 25, .04);
  --shadow-lg: 0 24px 60px -28px rgba(15, 32, 25, .28);
  --radius: 16px;
  --radius-sm: 10px;
  --radius-lg: 26px;
  --maxw: 1160px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
          "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC",
          "Noto Sans CJK SC", Roboto, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;
}

html[data-theme="dark"] {
  --bg: #0b1210;
  --bg-soft: #0f1a16;
  --surface: #121d19;
  --surface-2: #16221d;
  --ink: #e9f4ef;
  --ink-2: #cfe0d8;
  --muted: #93a8a0;
  --line: #22322c;
  --line-strong: #2e423a;
  --brand: #34d77a;
  --brand-2: #25d366;
  --brand-ink: #7ee7a8;
  --brand-soft: #12291d;
  --teal: #2dd4bf;
  --amber: #fbbf24;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, .4);
  --shadow: 0 10px 30px -16px rgba(0, 0, 0, .7);
  --shadow-lg: 0 30px 70px -30px rgba(0, 0, 0, .8);
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 16.5px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img, svg { max-width: 100%; height: auto; display: block; }

a { color: var(--brand-ink); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4 {
  color: var(--ink);
  line-height: 1.3;
  margin: 0 0 .6em;
  letter-spacing: -.015em;
  font-weight: 700;
}
h1 { font-size: clamp(1.85rem, 1.2rem + 2.4vw, 2.9rem); }
h2 { font-size: clamp(1.35rem, 1.05rem + 1.1vw, 1.85rem); }
h3 { font-size: clamp(1.08rem, 1rem + .35vw, 1.24rem); }

p { margin: 0 0 1.05em; }
ul, ol { margin: 0 0 1.1em; padding-left: 1.35em; }
li { margin-bottom: .45em; }
strong { color: var(--ink); font-weight: 700; }

hr { border: 0; border-top: 1px solid var(--line); margin: 2.5rem 0; }

code {
  font-family: var(--mono);
  font-size: .88em;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 1px 6px;
  word-break: break-word;
  color: var(--ink-2);
}

::selection { background: var(--brand-2); color: #062b14; }

:focus-visible {
  outline: 3px solid var(--brand-2);
  outline-offset: 2px;
  border-radius: 4px;
}

.container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: 20px;
}
.container-narrow { max-width: 820px; }

.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--brand); color: #fff;
  padding: 10px 16px; z-index: 999; border-radius: 0 0 8px 0;
}
.skip-link:focus { left: 0; }

/* ---------- 顶栏 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s, box-shadow .25s;
}
.site-header.is-stuck {
  border-bottom-color: var(--line);
  box-shadow: 0 6px 24px -20px rgba(15, 32, 25, .5);
}
.header-inner {
  display: flex; align-items: center; gap: 18px;
  min-height: 66px;
}
.brand {
  display: inline-flex; align-items: center; gap: 10px;
  font-weight: 800; font-size: 1.06rem; letter-spacing: -.02em;
  color: var(--ink); text-decoration: none; white-space: nowrap;
}
.brand:hover { text-decoration: none; color: var(--ink); }
.brand-mark {
  width: 34px; height: 34px; flex: 0 0 34px;
  border-radius: 11px;
  background: linear-gradient(150deg, var(--brand-2), #0f8b3f);
  display: grid; place-items: center;
  box-shadow: 0 6px 16px -8px rgba(23, 163, 74, .8);
}
.brand-mark svg { width: 19px; height: 19px; }
.brand small {
  display: block; font-size: .68rem; font-weight: 600;
  color: var(--muted); letter-spacing: .06em; line-height: 1;
}

.nav { margin-left: auto; }
.nav ul {
  display: flex; align-items: center; gap: 4px;
  list-style: none; margin: 0; padding: 0;
}
.nav a {
  display: block; padding: 8px 12px; border-radius: 9px;
  color: var(--ink-2); font-size: .93rem; font-weight: 500;
  text-decoration: none; transition: background .18s, color .18s;
}
.nav a:hover { background: var(--bg-soft); color: var(--ink); text-decoration: none; }
.nav a[aria-current="page"] { color: var(--brand-ink); background: var(--brand-soft); font-weight: 700; }

.header-actions { display: flex; align-items: center; gap: 8px; }

.icon-btn {
  width: 38px; height: 38px; display: grid; place-items: center;
  border: 1px solid var(--line); background: var(--surface);
  border-radius: 10px; cursor: pointer; color: var(--ink-2);
  transition: border-color .18s, background .18s, transform .18s;
}
.icon-btn:hover { border-color: var(--line-strong); background: var(--bg-soft); }
.icon-btn:active { transform: scale(.96); }

.nav-toggle { display: none; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 22px; border-radius: 12px;
  font-size: .95rem; font-weight: 700; letter-spacing: .01em;
  border: 1px solid transparent; cursor: pointer;
  text-decoration: none; transition: transform .16s, box-shadow .2s, background .2s, border-color .2s;
}
.btn:hover { text-decoration: none; }
.btn-primary {
  background: linear-gradient(160deg, var(--brand-2), var(--brand));
  color: #05301a;
  box-shadow: 0 10px 24px -14px rgba(23, 163, 74, .95);
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 16px 32px -16px rgba(23, 163, 74, .95); }
html[data-theme="dark"] .btn-primary { color: #04220f; }
.btn-ghost {
  background: var(--surface); color: var(--ink);
  border-color: var(--line-strong);
  box-shadow: var(--shadow-sm);
}
.btn-ghost:hover { background: var(--bg-soft); transform: translateY(-1px); }
.btn-sm { padding: 9px 16px; font-size: .87rem; border-radius: 10px; }

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden;
  padding: clamp(40px, 5vw, 76px) 0 clamp(36px, 4vw, 64px);
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(900px 420px at 82% -8%, rgba(37, 211, 102, .16), transparent 62%),
    radial-gradient(700px 380px at 8% 108%, rgba(13, 148, 136, .1), transparent 60%),
    var(--bg);
}
.hero-grid {
  display: grid; grid-template-columns: 1.08fr .92fr;
  gap: clamp(28px, 4vw, 56px); align-items: center;
}
.hero-copy { max-width: 620px; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: .78rem; font-weight: 700; letter-spacing: .1em;
  text-transform: uppercase; color: var(--brand-ink);
  background: var(--brand-soft); border: 1px solid rgba(23, 163, 74, .22);
  padding: 6px 13px; border-radius: 999px; margin-bottom: 18px;
}
.eyebrow .dot {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--brand); box-shadow: 0 0 0 4px rgba(23, 163, 74, .15);
}
.hero h1 { margin-bottom: 16px; }
.hero h1 .hl { color: var(--brand-ink); }
.lead { font-size: clamp(1rem, .96rem + .25vw, 1.12rem); color: var(--muted); margin-bottom: 26px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 26px; }
.hero-meta {
  display: flex; flex-wrap: wrap; gap: 8px 22px;
  font-size: .86rem; color: var(--muted); list-style: none; padding: 0; margin: 0;
}
.hero-meta li { display: flex; align-items: center; gap: 7px; margin: 0; }
.hero-meta svg { width: 15px; height: 15px; color: var(--brand); flex: 0 0 15px; }

/* 手机示意 */
.hero-art { display: grid; place-items: center; }
.phone {
  position: relative; width: min(322px, 88%);
  border-radius: 34px; padding: 12px;
  background: linear-gradient(165deg, #1b2b24, #0e1a15);
  box-shadow: var(--shadow-lg), 0 0 0 1px rgba(255, 255, 255, .06) inset;
}
.phone-screen {
  border-radius: 24px; overflow: hidden;
  background: #e9efe9;
  min-height: 430px; display: flex; flex-direction: column;
}
.chat-top {
  display: flex; align-items: center; gap: 9px;
  padding: 12px 13px; background: #0b7a44; color: #fff;
}
.chat-avatar {
  width: 30px; height: 30px; border-radius: 50%; flex: 0 0 30px;
  background: rgba(255, 255, 255, .22);
  display: grid; place-items: center; font-size: .78rem; font-weight: 700;
}
.chat-name { font-size: .82rem; font-weight: 700; line-height: 1.2; }
.chat-status { font-size: .66rem; opacity: .8; line-height: 1.3; }
.chat-body {
  flex: 1; padding: 12px 11px; display: flex; flex-direction: column; gap: 8px;
  background-image:
    linear-gradient(rgba(255, 255, 255, .55), rgba(255, 255, 255, .55)),
    repeating-linear-gradient(45deg, #dfe8e0 0 2px, transparent 2px 9px);
}
.bubble {
  max-width: 82%; padding: 8px 11px; border-radius: 11px;
  font-size: .76rem; line-height: 1.55; box-shadow: 0 1px 1px rgba(0, 0, 0, .07);
}
.bubble.in { background: #fff; color: #1f2d26; border-top-left-radius: 3px; align-self: flex-start; }
.bubble.out { background: #d9fdd3; color: #12301f; border-top-right-radius: 3px; align-self: flex-end; }
.bubble time { display: block; font-size: .6rem; opacity: .5; text-align: right; margin-top: 2px; }
.chat-input {
  display: flex; align-items: center; gap: 8px;
  padding: 8px 11px; background: #f3f7f4;
}
.chat-input .field {
  flex: 1; height: 30px; border-radius: 99px; background: #fff;
  border: 1px solid #dde6de;
}
.chat-input .send {
  width: 30px; height: 30px; border-radius: 50%; flex: 0 0 30px;
  background: #0b7a44; display: grid; place-items: center;
}
.chat-input .send svg { width: 15px; height: 15px; }
.badge-float {
  position: absolute; right: -14px; bottom: 62px;
  background: var(--surface); border: 1px solid var(--line);
  border-radius: 14px; padding: 10px 14px;
  box-shadow: var(--shadow);
  display: flex; align-items: center; gap: 9px;
  font-size: .78rem; font-weight: 700; color: var(--ink);
}
.badge-float svg { width: 18px; height: 18px; color: var(--brand); }
.badge-float small { display: block; font-weight: 500; color: var(--muted); font-size: .68rem; }

/* ---------- 通用区块 ---------- */
.section { padding: clamp(44px, 5vw, 76px) 0; }
.section-tight { padding: clamp(32px, 3.5vw, 52px) 0; }
.section-alt { background: var(--bg-soft); border-block: 1px solid var(--line); }
.section-head { max-width: 720px; margin-bottom: clamp(24px, 3vw, 38px); }
.section-head.center { margin-inline: auto; text-align: center; }
.section-head p { color: var(--muted); margin-bottom: 0; }
.kicker {
  font-size: .76rem; font-weight: 800; letter-spacing: .12em;
  text-transform: uppercase; color: var(--brand-ink); margin-bottom: 10px;
  display: block;
}

.grid { display: grid; gap: 18px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 24px;
  box-shadow: var(--shadow-sm);
  transition: transform .2s, box-shadow .24s, border-color .2s;
}
.card:hover { transform: translateY(-3px); box-shadow: var(--shadow); border-color: var(--line-strong); }
.card h3 { margin-bottom: .45em; }
.card p { color: var(--muted); margin-bottom: 0; font-size: .94rem; }
.card p + p { margin-top: .7em; }
.card .more { font-size: .88rem; font-weight: 700; display: inline-flex; align-items: center; gap: 5px; margin-top: 14px; }
.card-link { display: block; color: inherit; text-decoration: none; }
.card-link:hover { text-decoration: none; }

.card-icon {
  width: 44px; height: 44px; border-radius: 13px;
  display: grid; place-items: center; margin-bottom: 16px;
  background: var(--brand-soft); color: var(--brand-ink);
  border: 1px solid rgba(23, 163, 74, .16);
}
.card-icon svg { width: 21px; height: 21px; }
.card-icon.teal { background: color-mix(in srgb, var(--teal) 12%, transparent); color: var(--teal); border-color: color-mix(in srgb, var(--teal) 22%, transparent); }
.card-icon.amber { background: color-mix(in srgb, var(--amber) 12%, transparent); color: var(--amber); border-color: color-mix(in srgb, var(--amber) 22%, transparent); }
.card-icon.ink { background: var(--bg-soft); color: var(--ink-2); border-color: var(--line); }

/* 数字统计 */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
.stat {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 22px 20px; text-align: center;
}
.stat b {
  display: block; font-size: clamp(1.5rem, 1.2rem + 1vw, 2rem);
  color: var(--brand-ink); line-height: 1.2; letter-spacing: -.02em;
}
.stat span { font-size: .84rem; color: var(--muted); }

/* 步骤 */
.steps { list-style: none; padding: 0; margin: 0; counter-reset: step; display: grid; gap: 16px; }
.steps > li {
  counter-increment: step; position: relative;
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 20px 22px 20px 68px;
  margin: 0; box-shadow: var(--shadow-sm);
}
.steps > li::before {
  content: counter(step);
  position: absolute; left: 20px; top: 20px;
  width: 32px; height: 32px; border-radius: 10px;
  background: var(--brand-soft); color: var(--brand-ink);
  display: grid; place-items: center; font-weight: 800; font-size: .92rem;
  border: 1px solid rgba(23, 163, 74, .2);
}
.steps > li h3 { font-size: 1.03rem; margin-bottom: .3em; }
.steps > li p { margin: 0; color: var(--muted); font-size: .93rem; }
.steps.horizontal { grid-template-columns: repeat(3, 1fr); }
.steps.horizontal > li { padding: 22px 20px 20px; }
.steps.horizontal > li::before { position: static; margin-bottom: 12px; }

/* 正文排版 */
.prose { max-width: 820px; }
.prose h2 { margin-top: 2.2em; scroll-margin-top: 90px; }
.prose h2:first-child { margin-top: 0; }
.prose h3 { margin-top: 1.7em; scroll-margin-top: 90px; }
.prose p, .prose li { color: var(--ink-2); }
.prose ul, .prose ol { padding-left: 1.3em; }
.prose li::marker { color: var(--brand); }
.prose > .lead { color: var(--muted); font-size: 1.06rem; }

.note {
  border-left: 3px solid var(--brand);
  background: var(--brand-soft);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 16px 20px; margin: 1.6em 0; font-size: .93rem;
}
.note.warn { border-left-color: var(--amber); background: color-mix(in srgb, var(--amber) 9%, transparent); }
.note strong { display: block; margin-bottom: .3em; }
.note p:last-child { margin-bottom: 0; }

.table-wrap { overflow-x: auto; margin: 1.6em 0; border: 1px solid var(--line); border-radius: var(--radius-sm); }
table { width: 100%; border-collapse: collapse; font-size: .92rem; background: var(--surface); }
th, td { text-align: left; padding: 12px 16px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { background: var(--bg-soft); font-weight: 700; font-size: .86rem; color: var(--ink-2); white-space: nowrap; }
tr:last-child td { border-bottom: 0; }
td { color: var(--ink-2); }

/* 面包屑 */
.breadcrumb { padding: 18px 0 0; font-size: .84rem; color: var(--muted); }
.breadcrumb ol { display: flex; flex-wrap: wrap; align-items: center; gap: 7px; list-style: none; margin: 0; padding: 0; }
.breadcrumb li { margin: 0; display: flex; align-items: center; gap: 7px; }
.breadcrumb li + li::before { content: "/"; color: var(--line-strong); }
.breadcrumb a { color: var(--muted); }
.breadcrumb a:hover { color: var(--brand-ink); }
.breadcrumb [aria-current="page"] { color: var(--ink-2); font-weight: 600; }

/* 页头（内页） */
.page-head {
  padding: clamp(24px, 3vw, 40px) 0 clamp(28px, 3.4vw, 44px);
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(720px 320px at 88% -20%, rgba(37, 211, 102, .13), transparent 65%),
    var(--bg);
}
.page-head h1 { margin-bottom: 14px; }
.page-head .lead { margin-bottom: 0; max-width: 760px; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; padding: 0; list-style: none; }
.chips li { margin: 0; }
.chip {
  display: inline-block; font-size: .8rem; font-weight: 600;
  padding: 5px 12px; border-radius: 999px;
  background: var(--surface); border: 1px solid var(--line);
  color: var(--muted);
}
.chip.is-brand { background: var(--brand-soft); border-color: rgba(23, 163, 74, .22); color: var(--brand-ink); }

/* FAQ */
.faq-list { display: grid; gap: 12px; max-width: 860px; }
details.faq {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius-sm); padding: 0;
  box-shadow: var(--shadow-sm); overflow: hidden;
  transition: border-color .2s;
}
details.faq[open] { border-color: rgba(23, 163, 74, .35); }
details.faq > summary {
  cursor: pointer; list-style: none;
  padding: 16px 52px 16px 20px; position: relative;
  font-weight: 700; font-size: .98rem; color: var(--ink);
  transition: background .18s;
}
details.faq > summary::-webkit-details-marker { display: none; }
details.faq > summary:hover { background: var(--surface-2); }
details.faq > summary::after {
  content: ""; position: absolute; right: 20px; top: 50%;
  width: 9px; height: 9px; margin-top: -6px;
  border-right: 2px solid var(--muted); border-bottom: 2px solid var(--muted);
  transform: rotate(45deg); transition: transform .22s;
}
details.faq[open] > summary::after { transform: rotate(-135deg); margin-top: -2px; }
details.faq .faq-body { padding: 0 20px 18px; color: var(--ink-2); font-size: .94rem; border-top: 1px solid var(--line); padding-top: 16px; }
details.faq .faq-body p:last-child { margin-bottom: 0; }

/* CTA */
.cta {
  position: relative; overflow: hidden;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, #0b7a44, #14a05a 55%, #17b06a);
  color: #fff; padding: clamp(32px, 4vw, 54px);
  box-shadow: 0 30px 60px -34px rgba(11, 122, 68, .9);
}
.cta::after {
  content: ""; position: absolute; right: -70px; top: -70px;
  width: 260px; height: 260px; border-radius: 50%;
  background: rgba(255, 255, 255, .12);
}
.cta h2 { color: #fff; margin-bottom: 12px; }
.cta p { color: rgba(255, 255, 255, .88); max-width: 620px; margin-bottom: 24px; }
.cta .btn-primary {
  background: #fff; color: #0a5c33;
  box-shadow: 0 12px 28px -14px rgba(0, 0, 0, .5);
}
.cta .btn-ghost { background: rgba(255, 255, 255, .12); color: #fff; border-color: rgba(255, 255, 255, .38); }
.cta .btn-ghost:hover { background: rgba(255, 255, 255, .2); }
.cta .btn-group { display: flex; flex-wrap: wrap; gap: 12px; position: relative; z-index: 1; }

/* 页脚 */
.site-footer {
  margin-top: clamp(40px, 5vw, 72px);
  border-top: 1px solid var(--line);
  background: var(--surface);
  padding: clamp(36px, 4vw, 56px) 0 26px;
}
.footer-grid {
  display: grid; grid-template-columns: 1.6fr repeat(3, 1fr);
  gap: 32px 24px;
}
.footer-brand p { color: var(--muted); font-size: .9rem; max-width: 320px; margin: 14px 0 0; }
.footer-col h4 {
  font-size: .82rem; letter-spacing: .08em; text-transform: uppercase;
  color: var(--muted); margin-bottom: 14px; font-weight: 700;
}
.footer-col ul { list-style: none; padding: 0; margin: 0; }
.footer-col li { margin-bottom: 9px; }
.footer-col a { color: var(--ink-2); font-size: .92rem; }
.footer-col a:hover { color: var(--brand-ink); }
.footer-bottom {
  margin-top: 36px; padding-top: 20px; border-top: 1px solid var(--line);
  display: flex; flex-wrap: wrap; gap: 8px 18px; align-items: center;
  justify-content: space-between; font-size: .82rem; color: var(--muted);
}
.footer-bottom p { margin: 0; }
.footer-bottom nav { display: flex; gap: 16px; flex-wrap: wrap; }

.disclaimer {
  margin-top: 18px; font-size: .78rem; color: var(--muted);
  line-height: 1.7; max-width: 880px;
}

/* 返回顶部 */
.to-top {
  position: fixed; right: 20px; bottom: 24px; z-index: 90;
  width: 44px; height: 44px; border-radius: 50%;
  display: grid; place-items: center;
  background: var(--surface); border: 1px solid var(--line-strong);
  color: var(--ink-2); box-shadow: var(--shadow);
  cursor: pointer; opacity: 0; visibility: hidden;
  transform: translateY(10px); transition: all .25s;
}
.to-top.show { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { background: var(--brand-soft); color: var(--brand-ink); }

/* 目录（内页侧边） */
.with-aside { display: grid; grid-template-columns: 1fr 268px; gap: clamp(24px, 3.5vw, 48px); align-items: start; }
.aside {
  position: sticky; top: 86px;
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 20px 22px;
  font-size: .9rem;
}
.aside h2 { font-size: .8rem; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); margin-bottom: 12px; }
.aside ol { list-style: none; counter-reset: toc; padding: 0; margin: 0; }
.aside li { counter-increment: toc; margin-bottom: 8px; }
.aside a { color: var(--ink-2); display: flex; gap: 8px; }
.aside a::before { content: counter(toc) "."; color: var(--brand); font-weight: 700; font-variant-numeric: tabular-nums; }
.aside a:hover { color: var(--brand-ink); }

/* 提示条 */
.ticker {
  background: var(--surface); border-bottom: 1px solid var(--line);
  font-size: .82rem; color: var(--muted);
}
.ticker .container { display: flex; flex-wrap: wrap; gap: 6px 18px; padding-block: 8px; align-items: center; }
.ticker strong { color: var(--brand-ink); }

/* 404 */
.center-block { text-align: center; padding: clamp(60px, 10vw, 120px) 0; }
.center-block h1 { font-size: clamp(3.4rem, 8vw, 6rem); color: var(--brand); letter-spacing: -.03em; margin-bottom: 8px; }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-art { order: 2; }
  .hero-copy { max-width: none; }
  .hero { padding-top: clamp(28px, 4vw, 44px); }
  .phone { width: min(290px, 82%); }
  .phone-screen { min-height: 380px; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .with-aside { grid-template-columns: 1fr; }
  .aside { position: static; }
  .steps.horizontal { grid-template-columns: 1fr; }
}

@media (max-width: 860px) {
  .nav {
    position: fixed; inset: 66px 0 auto 0;
    background: var(--surface);
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow);
    padding: 10px 20px 18px;
    display: none;
    max-height: calc(100vh - 66px);
    overflow-y: auto;
  }
  .nav.is-open { display: block; }
  .nav ul { flex-direction: column; align-items: stretch; gap: 2px; }
  .nav a { padding: 12px 14px; font-size: 1rem; }
  .nav-toggle { display: grid; }
  .header-actions .btn-desktop { display: none; }
}

@media (max-width: 720px) {
  body { font-size: 16px; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 26px 18px; }
  .footer-brand { grid-column: 1 / -1; }
  .badge-float { right: 0; bottom: 40px; padding: 8px 12px; }
  .phone { width: min(258px, 76%); }
  .phone-screen { min-height: 336px; }
  .hero-actions .btn { flex: 1 1 auto; }
  .cta { border-radius: var(--radius); }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}

@media print {
  .site-header, .site-footer, .to-top, .cta, .aside { display: none; }
  body { background: #fff; }
}