/* ============================================================
   白金之笔 · 主域名营销页共享样式
   纸白轻奢 / 编辑排版 / 系统衬线字族(不依赖任何外部资源)
   ============================================================ */

:root {
  /* 色板:暖纸白 + 墨色 + 铜金 */
  --paper: #FBF9F4;
  --paper-deep: #F4F0E6;
  --card: #FFFFFF;
  --ink: #211D17;
  --ink-soft: #57534E;
  --ink-faint: #79736A;
  --gold: #A16207;
  --gold-deep: #7A5410;
  --gold-line: #D8C79E;
  --line: #E7E0D2;
  --ok: #3D6B4F;

  /* 字族:网页内嵌 Crimson Pro(西文衬线)+ 思源宋体(中文衬线)+ 阿里巴巴普惠体(正文),
     均为可商用授权(其中思源宋体/Crimson Pro 为 OFL 开源);后备仅剩访客设备系统字体(不随站点分发) */
  --font-display: "Crimson Pro", "Noto Serif SC", "Source Han Serif SC",
    "Songti SC", Georgia, "Times New Roman", serif;
  --font-body: "Alibaba PuHuiTi", "PingFang SC", "Noto Sans SC",
    "Segoe UI", system-ui, sans-serif;

  /* 间距节拍(8px 系)与圆角 */
  --sp-1: 8px;  --sp-2: 16px; --sp-3: 24px; --sp-4: 32px;
  --sp-5: 48px; --sp-6: 64px; --sp-7: 96px; --sp-8: 128px;
  --radius: 10px;
  --dur: 220ms;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --wrap: 1080px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* ---------- 通用 ---------- */
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 var(--sp-4); }

h1, h2, h3, .serif { font-family: var(--font-display); font-weight: 700; }

a { color: inherit; }
:focus-visible { outline: 2px solid var(--gold); outline-offset: 3px; border-radius: 2px; }

.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--ink); color: var(--paper);
  padding: 10px 16px; border-radius: 0 0 8px 0; z-index: 100;
}
.skip-link:focus { left: 0; }

/* 视觉隐藏、屏幕阅读器与搜索引擎可见 */
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

.eyebrow {
  font-size: 13px; letter-spacing: 0.22em; text-indent: 0.22em;
  color: var(--gold-deep); font-weight: 600;
}
.eyebrow .dot { color: var(--gold-line); margin: 0 6px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: var(--font-body); font-size: 16px; font-weight: 600;
  text-decoration: none; cursor: pointer;
  border-radius: 999px; transition: transform var(--dur) var(--ease),
    background var(--dur) var(--ease), box-shadow var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}
.btn-primary {
  background: var(--ink); color: var(--paper);
  padding: 14px 34px; box-shadow: 0 1px 0 rgba(33, 29, 23, 0.2);
}
.btn-primary:hover { background: #3A342B; transform: translateY(-1px); }
.btn-primary:active { transform: translateY(0); }
.btn-ghost {
  color: var(--ink-soft); padding: 14px 18px;
  border: 1px solid var(--line); border-radius: 999px; background: transparent;
}
.btn-ghost:hover { color: var(--ink); border-color: var(--gold-line); }
.btn .arrow { font-family: var(--font-display); }

/* ---------- 页眉 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(251, 249, 244, 0.88);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.site-header .wrap {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; }
.brand-mark { display: block; width: 26px; height: 26px; }
.brand-mark path {
  fill: none; stroke: #C9A24B; stroke-width: 1.6;
  stroke-linecap: round; stroke-linejoin: round;
}
.brand-mark circle { fill: #C9A24B; stroke: none; }
.brand-name {
  font-family: var(--font-display); font-size: 19px; font-weight: 700;
  letter-spacing: 0.12em;
}
.site-nav { display: flex; align-items: center; gap: var(--sp-4); }
.site-nav a.nav-link {
  font-size: 14px; color: var(--ink-soft); text-decoration: none;
  padding: 6px 2px; border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.site-nav a.nav-link:hover { color: var(--ink); border-bottom-color: var(--gold-line); }
.site-nav .btn-primary { padding: 9px 22px; font-size: 14px; }

/* 阅读进度细线 */
.progress {
  position: fixed; top: 0; left: 0; height: 2px; width: 100%;
  transform-origin: 0 50%; transform: scaleX(0);
  background: linear-gradient(90deg, var(--gold-line), var(--gold));
  z-index: 60; pointer-events: none;
}

/* ---------- 章节区块 ---------- */
.section { padding: var(--sp-8) 0; }
.section + .section { border-top: 1px solid var(--line); }
.section-tight { padding: var(--sp-7) 0; }

.section-head { margin-bottom: var(--sp-6); }
.section-head .no {
  font-family: var(--font-display); font-size: 15px; color: var(--gold);
  letter-spacing: 0.3em; display: block; margin-bottom: 10px;
}
.section-head h2 { font-size: clamp(26px, 4vw, 36px); line-height: 1.3; letter-spacing: 0.04em; }
.section-head .lead {
  margin-top: 14px; max-width: 38em; color: var(--ink-soft); font-size: 17px;
}

/* ---------- 首屏 ---------- */
.hero { padding: calc(var(--sp-8) + 16px) 0 var(--sp-8); position: relative; overflow: hidden; }
.hero::after {
  content: ""; position: absolute; right: -140px; top: -120px;
  width: 520px; height: 520px; border-radius: 50%;
  background: radial-gradient(closest-side, rgba(216, 199, 158, 0.28), transparent 70%);
  pointer-events: none;
}
.hero h1 {
  font-size: clamp(38px, 7vw, 64px); line-height: 1.22;
  letter-spacing: 0.05em; margin: 22px 0 24px;
}
.hero h1 .gilded { color: var(--gold-deep); }
.hero .sub { max-width: 34em; color: var(--ink-soft); font-size: 18px; }
.hero-cta { margin-top: var(--sp-5); display: flex; flex-wrap: wrap; gap: 14px; align-items: center; }
.hero-chips { margin-top: var(--sp-5); display: flex; flex-wrap: wrap; gap: 10px; }
.chip {
  font-size: 13px; color: var(--ink-soft);
  border: 1px solid var(--line); border-radius: 999px;
  padding: 6px 14px; background: var(--card);
}
.hero-note { margin-top: var(--sp-4); font-size: 13px; color: var(--ink-faint); }

/* ---------- 特性卡 ---------- */
.cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--sp-3); }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: var(--sp-4); transition: border-color var(--dur) var(--ease),
    transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.card:hover {
  border-color: var(--gold-line); transform: translateY(-2px);
  box-shadow: 0 10px 30px -18px rgba(33, 29, 23, 0.35);
}
.card .icon {
  width: 40px; height: 40px; border-radius: 9px;
  background: var(--paper-deep); border: 1px solid var(--line);
  display: grid; place-items: center; margin-bottom: 18px;
}
.card .icon svg { width: 20px; height: 20px; stroke: var(--gold-deep); }
.card h3 { font-size: 18px; margin-bottom: 8px; letter-spacing: 0.04em; }
.card p { font-size: 14.5px; color: var(--ink-soft); line-height: 1.8; }

/* ---------- 流程 ---------- */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--sp-4); counter-reset: step; }
.step { position: relative; padding-top: 18px; border-top: 1px solid var(--gold-line); }
.step .num {
  font-family: var(--font-display); font-size: 15px; color: var(--gold);
  letter-spacing: 0.18em; display: block; margin-bottom: 10px;
}
.step h3 { font-size: 18px; margin-bottom: 8px; }
.step p { font-size: 14.5px; color: var(--ink-soft); }
.steps-note { margin-top: var(--sp-5); display: flex; flex-wrap: wrap; gap: 10px; }

/* ---------- 工作台示意 ---------- */
.mock {
  background: var(--card); border: 1px solid var(--line); border-radius: 14px;
  box-shadow: 0 24px 60px -30px rgba(33, 29, 23, 0.28);
  overflow: hidden;
}
.mock-bar {
  display: flex; align-items: center; gap: 8px;
  padding: 12px 18px; border-bottom: 1px solid var(--line);
  background: var(--paper);
}
.mock-bar .dot { width: 9px; height: 9px; border-radius: 50%; background: var(--line); }
.mock-bar .dot:first-child { background: var(--gold-line); }
.mock-bar .title {
  margin-left: 8px; font-size: 12.5px; color: var(--ink-faint); letter-spacing: 0.06em;
}
.mock-body { display: grid; grid-template-columns: 200px 1fr 240px; min-height: 380px; }
.mock-col { padding: 20px; }
.mock-col + .mock-col { border-left: 1px solid var(--line); }

.mock-toc h4, .mock-editor h4, .mock-review h4 {
  font-size: 12px; letter-spacing: 0.2em; color: var(--ink-faint);
  font-weight: 600; margin-bottom: 14px; font-family: var(--font-body);
}
.toc-item {
  display: flex; justify-content: space-between; align-items: baseline; gap: 8px;
  padding: 9px 10px; border-radius: 8px; font-size: 13.5px;
}
.toc-item .t { font-family: var(--font-display); letter-spacing: 0.05em; }
.toc-item .s { font-size: 11px; color: var(--ink-faint); white-space: nowrap; }
.toc-item.active { background: var(--paper-deep); }
.toc-item.active .t { color: var(--gold-deep); }
.toc-item .s.done { color: var(--ok); }

.mock-editor .chapter-title {
  font-family: var(--font-display); font-size: 19px; letter-spacing: 0.08em;
  margin-bottom: 16px;
}
.mock-editor p { font-size: 14px; line-height: 2.05; color: var(--ink-soft); max-width: 30em; }
.mock-editor p + p { margin-top: 10px; text-indent: 2em; }
.mock-editor .caret {
  display: inline-block; width: 1px; height: 15px; background: var(--gold);
  vertical-align: -2px; margin-left: 2px;
}

.review-card {
  border: 1px solid var(--line); border-radius: 10px; padding: 14px;
  background: var(--paper); margin-bottom: 12px;
}
.review-card .head {
  display: flex; justify-content: space-between; align-items: center; margin-bottom: 10px;
}
.review-card .head b { font-size: 13px; letter-spacing: 0.05em; }
.review-card .head .round { font-size: 11px; color: var(--gold-deep); }
.review-card ul { list-style: none; }
.review-card li {
  font-size: 12.5px; color: var(--ink-soft); line-height: 1.7;
  padding-left: 14px; position: relative; margin-bottom: 6px;
}
.review-card li::before {
  content: ""; position: absolute; left: 0; top: 9px;
  width: 5px; height: 5px; border-radius: 50%; background: var(--gold-line);
}
.review-chips { display: flex; gap: 8px; }
.review-chips span {
  font-size: 11.5px; padding: 5px 12px; border-radius: 999px;
  border: 1px solid var(--line); color: var(--ink-soft); background: var(--card);
}
.review-chips span.go { border-color: var(--gold-line); color: var(--gold-deep); }
.mock-foot {
  padding: 12px 20px; border-top: 1px solid var(--line);
  font-size: 12px; color: var(--ink-faint); background: var(--paper);
}

/* ---------- 尾声 CTA ---------- */
.finale { background: var(--paper-deep); border-top: 1px solid var(--gold-line); text-align: center; }
.finale h2 { font-size: clamp(28px, 4.6vw, 42px); letter-spacing: 0.06em; line-height: 1.35; }
.finale p { margin: 16px auto 0; max-width: 30em; color: var(--ink-soft); }
.finale .hero-cta { justify-content: center; margin-top: var(--sp-5); }
.finale .seal {
  margin: 0 auto var(--sp-4); width: 44px; height: 44px;
  display: grid; place-items: center;
  border: 1px solid var(--gold-line); border-radius: 50%; background: var(--card);
}
.finale .seal svg { width: 20px; height: 20px; stroke: var(--gold-deep); }

/* ---------- 关于 ---------- */
.about p { max-width: 40em; color: var(--ink-soft); }
.about p + p { margin-top: 12px; }
.about .fine { margin-top: 18px; font-size: 13px; color: var(--ink-faint); }

/* ---------- 页脚(备案区) ---------- */
.site-footer { border-top: 1px solid var(--line); background: var(--paper); }
.site-footer .wrap { padding-top: var(--sp-5); padding-bottom: var(--sp-5); }
.foot-brand {
  font-family: var(--font-display); font-size: 16px; letter-spacing: 0.1em;
  margin-bottom: 6px;
}
.foot-desc { font-size: 13.5px; color: var(--ink-soft); margin-bottom: var(--sp-4); }
.beian-row {
  display: flex; flex-wrap: wrap; align-items: center; gap: 12px 24px;
  padding-top: var(--sp-3); border-top: 1px solid var(--line);
  font-size: 13.5px; color: var(--ink-soft);
}
.beian-row a { text-decoration: none; color: var(--ink-soft); transition: color var(--dur) var(--ease); }
.beian-row a:hover { color: var(--gold-deep); text-decoration: underline; text-underline-offset: 3px; }
.beian-ga { display: inline-flex; align-items: center; gap: 7px; }
.beian-ga svg { width: 15px; height: 15px; stroke: var(--ink-faint); }
.foot-links { display: flex; gap: 20px; margin-left: auto; }
.foot-copy { margin-top: 14px; font-size: 12.5px; color: var(--ink-faint); }

/* ---------- 占位法务页 ---------- */
.legal-main { padding: var(--sp-7) 0 var(--sp-8); }
.legal-main h1 { font-size: clamp(26px, 4vw, 34px); margin: 16px 0 18px; letter-spacing: 0.05em; }
.legal-note {
  border-left: 2px solid var(--gold-line); padding: 4px 0 4px 18px;
  color: var(--ink-soft); max-width: 36em;
}
.legal-back { margin-top: var(--sp-5); }

/* ---------- 浮现动效(仅在 JS 可用时启用;无 JS 内容默认可见) ---------- */
.js [data-reveal] { opacity: 0; transform: translateY(12px); }
.js [data-reveal].is-revealed {
  opacity: 1; transform: none;
  transition: opacity 400ms var(--ease), transform 400ms var(--ease);
}

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .cards { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .mock-body { grid-template-columns: 170px 1fr; }
  .mock-review { display: none; }
}
@media (max-width: 640px) {
  .section { padding: var(--sp-7) 0; }
  .site-nav .nav-link { display: none; }
  .hero { padding-top: var(--sp-7); }
  .cards { grid-template-columns: 1fr; }
  .steps { grid-template-columns: 1fr; }
  .mock-body { grid-template-columns: 1fr; }
  .mock-col + .mock-col { border-left: 0; border-top: 1px solid var(--line); }
  .mock-toc { display: flex; flex-wrap: wrap; gap: 6px; align-items: center; }
  .mock-toc h4 { width: 100%; margin-bottom: 4px; }
  .toc-item { padding: 6px 10px; }
  .foot-links { margin-left: 0; }
}