/**
 * [INPUT]: 依赖 index.html 与 privacy.html 的语义结构、icon.png 和 product-screenshot.jpg 的本地资源
 * [OUTPUT]: 提供纸墨蓝设计令牌、落地页节奏、产品截图框架、隐私长文排版与移动端响应
 * [POS]: privacy-site 的唯一视觉系统，不加载外部字体、脚本、分析服务或远程资源
 * [PROTOCOL]: 变更时更新此头部，然后检查 AGENTS.md
 */

:root {
  --paper: #f5f1e8;
  --paper-deep: #e9e2d3;
  --ink: #14223a;
  --muted: #657083;
  --line: #cfd3d8;
  --blue: #1e58c7;
  --blue-dark: #143d8f;
  --white: #fffdf8;
  --green: #28765b;
  --shadow: 0 24px 70px rgb(20 34 58 / 14%);
  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", SimSun, serif;
  --sans: "Microsoft YaHei UI", "PingFang SC", "Noto Sans CJK SC", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  line-height: 1.75;
  text-rendering: optimizeLegibility;
}

img {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
}

a:focus-visible {
  outline: 3px solid rgb(30 88 199 / 35%);
  outline-offset: 4px;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.brand img {
  border-radius: 10px;
  box-shadow: 0 6px 16px rgb(20 34 58 / 16%);
}

nav {
  display: flex;
  gap: 26px;
  color: #38465c;
  font-size: 14px;
}

nav a {
  text-decoration: none;
}

nav a:hover,
nav a[aria-current="page"] {
  color: var(--blue);
}

.section-shell {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.7fr) minmax(260px, 0.7fr);
  gap: clamp(48px, 8vw, 110px);
  align-items: end;
  min-height: 650px;
  padding: 110px 0 90px;
}

.kicker {
  margin: 0 0 22px;
  color: var(--blue);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.19em;
}

.hero h1 {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(52px, 7.5vw, 102px);
  font-weight: 700;
  letter-spacing: -0.055em;
  line-height: 1.04;
}

.hero h1 em {
  color: var(--blue);
  font-style: normal;
}

.hero-lede {
  max-width: 720px;
  margin: 34px 0 0;
  color: #445168;
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 36px;
}

.button {
  display: inline-flex;
  align-items: center;
  min-height: 48px;
  padding: 0 20px;
  border: 1px solid var(--ink);
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
}

.button-primary {
  border-color: var(--blue);
  color: #fff;
  background: var(--blue);
}

.button-quiet:hover {
  color: #fff;
  background: var(--ink);
}

.trust-line {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  margin: 30px 0 0;
  padding: 0;
  color: var(--green);
  font-size: 13px;
  font-weight: 700;
  list-style: none;
}

.trust-line li::before {
  content: "●";
  margin-right: 8px;
  font-size: 8px;
  vertical-align: 2px;
}

.hero-note {
  padding: 24px 0 10px 28px;
  border-left: 2px solid var(--blue);
}

.hero-note .note-index {
  display: block;
  margin-bottom: 30px;
  color: var(--blue);
  font-family: var(--serif);
  font-size: 52px;
  line-height: 1;
}

.hero-note p {
  margin: 10px 0;
  font-family: var(--serif);
  font-size: 17px;
}

.product-proof,
.workflow,
.limits {
  padding: 110px 0;
  border-top: 1px solid var(--line);
}

.section-heading {
  display: grid;
  grid-template-columns: 0.85fr 1.45fr 1fr;
  gap: 36px;
  align-items: start;
  margin-bottom: 50px;
}

.section-heading h2,
.privacy-grid h2,
.policy-summary h2 {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(34px, 4.4vw, 56px);
  letter-spacing: -0.04em;
  line-height: 1.18;
}

.section-heading > p:last-child {
  margin: 4px 0 0;
  color: var(--muted);
}

.section-heading.narrow {
  grid-template-columns: 0.55fr 1.45fr;
}

.screenshot-frame {
  margin: 0;
  padding: 18px;
  border: 1px solid #bdc4cd;
  background: var(--white);
  box-shadow: var(--shadow);
}

.screenshot-frame img {
  width: 100%;
  border: 1px solid #dfe3e8;
}

.screenshot-frame figcaption {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 14px 4px 0;
  color: var(--muted);
  font-size: 12px;
}

.screenshot-frame figcaption span {
  color: var(--blue);
  font-weight: 800;
  letter-spacing: 0.08em;
}

.step-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--ink);
  list-style: none;
}

.step-list li {
  min-height: 280px;
  padding: 26px 30px 30px 0;
  border-right: 1px solid var(--line);
}

.step-list li + li {
  padding-left: 30px;
}

.step-list li:last-child {
  border-right: 0;
}

.step-number {
  color: var(--blue);
  font-family: var(--serif);
  font-size: 34px;
}

.step-list h3 {
  margin: 54px 0 12px;
  font-family: var(--serif);
  font-size: 26px;
}

.step-list p {
  margin: 0;
  color: var(--muted);
}

.privacy-board {
  color: #edf3ff;
  background: var(--ink);
}

.privacy-grid {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 90px;
  padding-top: 100px;
  padding-bottom: 100px;
}

.kicker-light {
  color: #8fb4ff;
}

.privacy-lede {
  color: #b9c4d7;
  font-size: 17px;
}

.boundary-list {
  margin: 0;
  border-top: 1px solid #536076;
}

.boundary-list div {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 24px;
  padding: 22px 0;
  border-bottom: 1px solid #536076;
}

.boundary-list dt {
  color: #8fb4ff;
  font-weight: 800;
}

.boundary-list dd {
  margin: 0;
  color: #d7dfec;
}

.limit-copy {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  color: #4d596c;
  font-family: var(--serif);
  font-size: 20px;
}

.site-footer {
  display: grid;
  grid-template-columns: 1fr 1fr 1.3fr;
  gap: 30px;
  align-items: center;
  padding: 34px max(20px, calc((100% - 1180px) / 2));
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 12px;
}

.site-footer p {
  margin: 0;
}

.footer-links {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 6px;
  text-align: right;
}

.policy-layout {
  display: grid;
  grid-template-columns: minmax(260px, 0.7fr) minmax(0, 1.6fr);
  gap: clamp(50px, 8vw, 120px);
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
  padding: 90px 0 120px;
}

.policy-aside {
  position: sticky;
  top: 30px;
  align-self: start;
  padding-right: 32px;
  border-right: 1px solid var(--line);
}

.policy-aside h1 {
  margin: 0 0 24px;
  font-family: var(--serif);
  font-size: clamp(44px, 6vw, 72px);
  letter-spacing: -0.05em;
  line-height: 1;
}

.policy-aside > p:not(.kicker) {
  color: var(--muted);
}

.policy-aside dl {
  margin: 40px 0 0;
}

.policy-aside dl div {
  display: grid;
  grid-template-columns: 86px 1fr;
  padding: 10px 0;
  border-bottom: 1px solid var(--line);
  font-size: 13px;
}

.policy-aside dt {
  color: var(--muted);
}

.policy-aside dd {
  margin: 0;
  font-weight: 700;
}

.policy-article {
  max-width: 760px;
}

.policy-article section {
  padding: 42px 0;
  border-bottom: 1px solid var(--line);
}

.policy-article section:first-child {
  padding-top: 0;
}

.policy-summary {
  padding: 32px !important;
  border: 1px solid #b9c1cc !important;
  background: var(--white);
  box-shadow: 10px 10px 0 var(--paper-deep);
}

.policy-summary h2 {
  font-size: clamp(30px, 4vw, 44px);
}

.policy-article h2 {
  margin: 0 0 18px;
  font-family: var(--serif);
  font-size: 28px;
  letter-spacing: -0.025em;
}

.policy-article h3 {
  margin: 28px 0 8px;
  color: var(--blue-dark);
  font-size: 16px;
}

.policy-article p,
.policy-article li {
  color: #465268;
}

.policy-article ul {
  padding-left: 22px;
}

.policy-article code {
  padding: 2px 5px;
  border: 1px solid #c7ced8;
  background: #fff;
  font-family: Consolas, monospace;
  font-size: 0.88em;
}

.policy-footer {
  display: flex;
  justify-content: space-between;
}

@media (max-width: 820px) {
  .site-header {
    align-items: flex-start;
  }

  nav {
    flex-wrap: wrap;
    justify-content: flex-end;
    gap: 8px 16px;
  }

  .hero,
  .privacy-grid,
  .policy-layout {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
    padding: 80px 0 70px;
  }

  .hero-note,
  .policy-aside {
    position: static;
    border-right: 0;
    border-left: 2px solid var(--blue);
  }

  .policy-aside {
    padding-left: 24px;
  }

  .section-heading,
  .section-heading.narrow {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .step-list {
    grid-template-columns: 1fr;
  }

  .step-list li,
  .step-list li + li {
    min-height: 0;
    padding: 24px 0;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .step-list h3 {
    margin-top: 18px;
  }

  .limit-copy,
  .site-footer {
    grid-template-columns: 1fr;
  }

  .footer-links {
    align-items: flex-start;
    text-align: left;
  }
}

@media (max-width: 540px) {
  .site-header {
    width: min(100% - 28px, 1180px);
  }

  .site-header nav a:not([aria-current="page"]):not(:last-child) {
    display: none;
  }

  .section-shell,
  .policy-layout {
    width: min(100% - 28px, 1180px);
  }

  .hero h1 {
    font-size: 48px;
  }

  .product-proof,
  .workflow,
  .limits {
    padding: 78px 0;
  }

  .screenshot-frame {
    padding: 8px;
  }

  .screenshot-frame figcaption {
    display: block;
  }

  .privacy-grid {
    gap: 50px;
    padding-top: 76px;
    padding-bottom: 76px;
  }

  .boundary-list div {
    grid-template-columns: 1fr;
    gap: 4px;
  }

  .policy-layout {
    padding: 64px 0 90px;
  }

  .policy-summary {
    padding: 22px !important;
    box-shadow: 7px 7px 0 var(--paper-deep);
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}