@charset "UTF-8";
/* =============================================================================
   内容页共享样式（关于我们 / 在线教程）— public 静态页专用
   ⚠️ public/css/content-pages.css 由本文件编译生成，请勿直接编辑 CSS 产物！
   编译：npm run content-css（predev / build 前自动执行）
         npm run content-css:watch（开发时监听）
   视觉标准与主应用 design.md 完全一致：
   - 令牌值逐一对齐 src/styles/tokens 与 global.scss :root（浅/深双主题）
   - 顶栏毛玻璃：backdrop-filter 可用时降为 0.72 + saturate(180%) blur(2px)，
     不可用的旧浏览器保持 0.88 实色玻璃（值与主应用 --blur-bg 一致）
   - transition 只声明具体属性，禁 all；缓动统一 cubic-bezier(0.4, 0, 0.2, 1)
   - 内联 SVG 必须显式 width/height（iOS 16）
   唯一刻意差异：正文 15px / 1.7（阅读型页面），主应用为 14px。
   内容页排版语言（2026-08 重构，纯文档风格）：
   - 页面底 = 纯白（浅）/ 纯黑（深）阅读底；全页无卡片盒、无彩色装饰，
     层级只靠字号阶梯与三级灰（accent 仅出现于链接/按钮/选中态）
   - hero 左对齐：h1 40px/1.15（移动 30px）+ 17px lead；次级入口用 .hero-link
     文本链（无按钮盒），主 CTA 保留 nav-btn--primary
   - 节标题 h2 纯排版（无任何装饰元素）；节间距 80px（移动 48px）；
   - 参数徽章 .badge = 行内 code 语言：等宽 + --card-2 底 + --border 描边；
     .tip 提示 = 中性灰左线 callout（2px --border-strong 左缘 + 12px 内缩，
     13px / 500 字重 / 微字距 / --text-3，无底色）
   - about 信任区 = 朴素段落组（.about-card：小标题 + 描述，仅靠留白分组）；
     联系方式 .contact-card 扁平化为段落强调链接
   - 教程侧栏 .tut-toc 无盒纯列表 + 小标题（移动端转柔灰胶囊条：
     --dropdown-hover-bg 填充、无描边无阴影，选中 = accent 0.12 浅底，标题隐藏）；
     步骤序号 .step-card__num 桌面为纯排版大灰数字，移动端隐去
     （不可点击元素不做交互暗示）；
     .faq 手风琴 = 柔灰填充盒（--card-3，无描边无阴影），展开时
     summary 衬 --card-3 底与答案分隔，JS 高度动画展开/收起，
     + 图标垂直居中、绕自身中心旋转且与高度动画同步（收起经 .is-closing 覆盖）
   - 小节滚动进视口一截展开 / 近乎全离收起（JS 挂 .sec-anim + is-in，
     IntersectionObserver 驱动；无 JS / reduced-motion 时内容天然可见）
   ============================================================================= */
:root {
  --accent: #007aff;
  --accent-hover: #0066d6;
  --accent-rgb: 0, 122, 255;
  --text: #1d1d1f;
  --text-2: #6e6e73;
  --text-3: #86868b;
  --border: rgba(0, 0, 0, 0.08);
  --border-strong: rgba(0, 0, 0, 0.12);
  --card: #ffffff;
  --card-2: #fbfbfd;
  --card-3: #f1f1f1;
  --page-bg: #ffffff;
  --glass-bg: rgba(255, 255, 255, 0.88);
  --shadow-xs: 0 1px 3px rgba(0, 0, 0, 0.04);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow: 0 12px 40px rgba(0, 0, 0, 0.1);
  --shadow-hover: 0 2px 12px rgba(0, 0, 0, 0.08);
  --shadow-btn-primary: 0 2px 8px rgba(0, 122, 255, 0.3);
  --shadow-btn-primary-hover: 0 4px 14px rgba(0, 122, 255, 0.4);
  --dropdown-hover-bg: #e5e5ea;
  --tut-toc-bg: #f2f4f7d1;
  --faq-hover: #e5e5e5;
  --dropdown-radius: 20px;
  --radius: 16px;
  --radius-sm: 10px;
  --radius-xs: 8px;
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

html[data-theme=dark] {
  --accent: #0a84ff;
  --accent-hover: #409cff;
  --accent-rgb: 10, 132, 255;
  --text: #f5f5f7;
  --text-2: #aeaeb2;
  --text-3: #8e8e93;
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.15);
  --card: #2c2c2e;
  --card-2: #3a3a3c;
  --card-3: #3a3a3c;
  --page-bg: #000000;
  --glass-bg: rgba(28, 28, 30, 0.88);
  --shadow-xs: 0 1px 3px rgba(0, 0, 0, 0.15);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.25);
  --shadow: 0 12px 40px rgba(0, 0, 0, 0.5);
  --shadow-hover: 0 2px 12px rgba(0, 0, 0, 0.35);
  --shadow-btn-primary: 0 2px 8px rgba(10, 132, 255, 0.3);
  --shadow-btn-primary-hover: 0 4px 14px rgba(10, 132, 255, 0.4);
  --dropdown-hover-bg: rgba(255, 255, 255, 0.12);
  --tut-toc-bg: rgba(255, 255, 255, 0.12);
  --faq-hover: rgba(255, 255, 255, 0.12);
}

* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--page-bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Inter", "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 15px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color 0.4s var(--ease), color 0.4s var(--ease);
}

a {
  color: var(--accent);
}

img {
  max-width: 100%;
}

::selection {
  background: rgba(var(--accent-rgb), 0.2);
  color: var(--text);
}

::-webkit-scrollbar {
  width: 4px;
  height: 4px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 2px;
}

.nav-btn:focus-visible,
.tut-toc a:focus-visible,
.faq summary:focus-visible,
.content-footer__links a:focus-visible,
.contact-card a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: var(--radius-xs);
}

@keyframes content-in {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}
.page,
.content-footer {
  animation: content-in 0.4s var(--ease) both;
}
@media (prefers-reduced-motion: reduce) {
  .page,
  .content-footer {
    animation: none;
  }
}

.content-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 13.5px 20px;
  background: var(--glass-bg);
  border-bottom: 1px solid var(--border);
}
@media (max-width: 833px) {
  .content-nav {
    padding: 11.5px 14px;
  }
}
@supports (backdrop-filter: blur(2px)) or (-webkit-backdrop-filter: blur(2px)) {
  .content-nav {
    background: rgba(255, 255, 255, 0.72);
    -webkit-backdrop-filter: saturate(180%) blur(2px);
    backdrop-filter: saturate(180%) blur(2px);
  }
  html[data-theme=dark] .content-nav {
    background: rgba(28, 28, 30, 0.72);
  }
}
.content-nav__brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
  font-weight: 600;
  font-size: 17px;
  letter-spacing: -0.02em;
  min-width: 0;
}
@media (max-width: 833px) {
  .content-nav__brand {
    font-size: 15px;
  }
}
.content-nav__logo {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  border-radius: 9px;
  background: linear-gradient(135deg, #007aff, #5856d6);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  box-shadow: 0 4px 12px rgba(var(--accent-rgb), 0.4);
}
.content-nav__logo img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  border-radius: 9px;
}
@media (max-width: 480px) {
  .content-nav__logo {
    width: 28px;
    height: 28px;
    border-radius: 8px;
  }
  .content-nav__logo img {
    border-radius: 8px;
  }
}
.content-nav__name {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
@media (max-width: 480px) {
  .content-nav__name {
    font-size: 14px;
  }
}
.content-nav__actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}
.content-nav .nav-btn {
  height: 34px;
  padding: 0 14px;
  border: none;
  font-size: 14px;
}
.content-nav .nav-btn:hover {
  transform: none;
}

.nav-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--text);
  font-size: 14px;
  font-weight: 500;
  font-family: inherit;
  line-height: 1.2;
  cursor: pointer;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color 0.25s var(--ease), border-color 0.25s var(--ease), color 0.25s var(--ease), transform 0.25s var(--ease), box-shadow 0.25s var(--ease);
}
.nav-btn:hover {
  background: var(--card-2);
  transform: translateY(-1px);
}
.nav-btn:active {
  transform: translateY(0);
}
.nav-btn svg {
  flex-shrink: 0;
}
.nav-btn--primary {
  background: var(--accent);
  border-color: transparent;
  color: #ffffff;
  box-shadow: var(--shadow-btn-primary);
}
.nav-btn--primary:hover {
  background: var(--accent-hover);
  box-shadow: var(--shadow-btn-primary-hover);
  color: #ffffff;
}
.nav-btn--quaternary {
  background: transparent;
  border-color: transparent;
}
.nav-btn--quaternary:hover {
  background: var(--card-2);
  transform: none;
}
@media (max-width: 480px) {
  .nav-btn__label {
    display: none;
  }
}
@media (max-width: 833px) {
  .nav-btn {
    padding: 7px 12px;
    font-size: 13px;
  }
}
@media (max-width: 480px) {
  .nav-btn {
    padding: 7px 10px;
  }
}

.theme-icon--dark {
  display: none;
}

html[data-theme=dark] .theme-icon--light {
  display: none;
}
html[data-theme=dark] .theme-icon--dark {
  display: block;
}

.dropdown {
  position: relative;
}
.dropdown.open .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) scale(1);
  transition: opacity 0.3s var(--ease), transform 0.3s var(--ease), visibility 0s;
  pointer-events: auto;
}

.dropdown-menu {
  position: absolute;
  top: calc(100% + 6px);
  left: 50%;
  width: max-content;
  padding: 4px 0;
  display: flex;
  flex-direction: column;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--dropdown-radius);
  box-shadow: var(--shadow);
  opacity: 0;
  visibility: hidden;
  transform: translateX(-50%) scale(0.9);
  transform-origin: top center;
  transition: opacity 0.3s var(--ease), transform 0.3s var(--ease), visibility 0s linear 0.3s;
  pointer-events: none;
  z-index: 200;
}
.dropdown-menu button,
.dropdown-menu a {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 34px;
  margin: 8px 12px;
  padding: 0 12px;
  border: none;
  background: transparent;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 14px;
  color: var(--text-2);
  text-align: center;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color 0.2s var(--ease), color 0.2s var(--ease);
}
.dropdown-menu button:hover,
.dropdown-menu a:hover {
  background: var(--dropdown-hover-bg);
}

#theme-dropdown .dropdown-menu {
  left: auto;
  right: 0;
  transform: scale(0.9);
  transform-origin: top right;
}
#theme-dropdown.open .dropdown-menu {
  transform: scale(1);
}

.page {
  max-width: 880px;
  margin: 0 auto;
  padding: 48px 24px;
}
@media (max-width: 833px) {
  .page {
    padding: 40px 50px 20px;
  }
}

.page-hero {
  margin-bottom: 80px;
}
.page-hero h1 {
  margin: 0;
  font-size: 40px;
  line-height: 1.15;
  font-weight: 700;
  letter-spacing: -0.02em;
}
.page-hero .lead {
  margin: 14px 0 24px;
  font-size: 17px;
  line-height: 1.6;
  color: var(--text-2);
}
@media (max-width: 833px) {
  .page-hero {
    margin-bottom: 48px;
  }
  .page-hero h1 {
    font-size: 30px;
  }
  .page-hero .lead {
    font-size: 15px;
  }
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 12px 24px;
  flex-wrap: wrap;
}
.hero-actions .nav-btn {
  padding: 10px 20px;
  font-size: 14px;
}

.hero-link {
  color: var(--accent);
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  transition: color 0.2s var(--ease);
}
.hero-link:hover {
  color: var(--accent-hover);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.section {
  margin: 80px 0;
  scroll-margin-top: 76px;
}
.section:first-of-type {
  margin-top: 0;
}
.section:last-of-type {
  margin-bottom: 0;
}
.section h2 {
  margin: 0 0 18px;
  font-size: 22px;
  line-height: 1.35;
  font-weight: 700;
  letter-spacing: -0.02em;
}
.section p {
  color: var(--text-2);
  margin: 8px 0;
  text-align: justify;
}
.section ul,
.section ol {
  color: var(--text-2);
  margin: 8px 0;
  padding-left: 22px;
}
.section li {
  margin: 5px 0;
  text-align: justify;
}
.section li::marker {
  color: var(--text-3);
}
.section strong {
  color: var(--text);
  font-weight: 600;
}
@media (max-width: 833px) {
  .section {
    margin: 48px 0;
    scroll-margin-top: 66px;
  }
  .section h2 {
    font-size: 19px;
  }
}

.section.sec-anim {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s var(--ease), transform 0.5s var(--ease);
}
.section.sec-anim.is-in {
  opacity: 1;
  transform: none;
}

.badge {
  display: inline-block;
  padding: 1px 7px;
  border-radius: 6px;
  background: var(--card-2);
  border: 1px solid var(--border);
  color: var(--text);
  font-family: ui-monospace, "SF Mono", monospace;
  font-size: 13px;
  font-weight: 500;
  line-height: 1.5;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.about-card {
  margin-top: 24px;
}
.about-card h3 {
  margin: 0 0 4px;
  font-size: 15px;
  font-weight: 600;
}
.about-card p {
  margin: 0;
  font-size: 14px;
  color: var(--text-2);
}

.contact-card {
  padding: 6px 0 0;
}
.contact-card a {
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
}
.contact-card a:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}
.contact-card .contact-note {
  margin-top: 4px;
  font-size: 12px;
  color: var(--text-3);
}

.tut-layout {
  display: grid;
  grid-template-columns: 190px 1fr;
  gap: 32px;
  align-items: start;
}
@media (max-width: 833px) {
  .tut-layout {
    grid-template-columns: 1fr;
    gap: 20px;
  }
}

.tut-toc {
  position: sticky;
  top: 76px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.tut-toc__title {
  padding: 7px 10px 5px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--text-3);
}
.tut-toc a {
  padding: 7px 10px;
  border-radius: var(--radius-xs);
  font-size: 13px;
  color: var(--text-2);
  text-decoration: none;
  transition: color 0.2s var(--ease), background-color 0.2s var(--ease);
}
.tut-toc a:hover {
  color: var(--accent);
}
.tut-toc a.active {
  color: var(--accent);
  background: rgba(var(--accent-rgb), 0.12);
  font-weight: 600;
}
@media (hover: none) {
  .tut-toc a:hover {
    color: var(--text-2);
  }
  .tut-toc a.active:hover {
    color: var(--accent);
  }
}
@media (max-width: 833px) {
  .tut-toc {
    position: static;
    flex-direction: row;
    gap: 8px;
    overflow-x: auto;
    padding: 2px;
    background: transparent;
    border: none;
    box-shadow: none;
    border-radius: 0;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }
  .tut-toc::-webkit-scrollbar {
    display: none;
  }
  .tut-toc .tut-toc__title {
    display: none;
  }
  .tut-toc a {
    flex-shrink: 0;
    white-space: nowrap;
    padding: 6px 14px;
    border-radius: 999px;
    background: var(--tut-toc-bg);
    font-weight: 500;
    transition: background-color 0.2s var(--ease), color 0.2s var(--ease);
  }
  .tut-toc a.active {
    background: rgba(var(--accent-rgb), 0.12);
    color: var(--accent);
    font-weight: 600;
  }
  .tut-toc--can-right {
    -webkit-mask-image: linear-gradient(90deg, #000 calc(100% - 28px), transparent);
    mask-image: linear-gradient(90deg, #000 calc(100% - 28px), transparent);
  }
  .tut-toc--can-left {
    -webkit-mask-image: linear-gradient(90deg, transparent, #000 28px);
    mask-image: linear-gradient(90deg, transparent, #000 28px);
  }
  .tut-toc--can-left.tut-toc--can-right {
    -webkit-mask-image: linear-gradient(90deg, transparent, #000 28px, #000 calc(100% - 28px), transparent);
    mask-image: linear-gradient(90deg, transparent, #000 28px, #000 calc(100% - 28px), transparent);
  }
}

.tut-toc-wrap {
  display: contents;
}
@media (max-width: 833px) {
  .tut-toc-wrap {
    display: block;
    position: relative;
    min-width: 0;
  }
}

@keyframes toc-hint-nudge {
  0%, 100% {
    transform: translate(0, -50%);
  }
  50% {
    transform: translate(var(--hint-nudge, 3px), -50%);
  }
}
.tut-toc-hint {
  display: none;
}
@media (max-width: 833px) {
  .tut-toc-hint {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    z-index: 2;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6px;
    color: rgba(0, 0, 0, 0.28);
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.25s var(--ease);
    animation: toc-hint-nudge 1.6s var(--ease) infinite;
  }
  html[data-theme=dark] .tut-toc-hint {
    color: rgba(255, 255, 255, 0.55);
  }
  .tut-toc-hint--right {
    right: 3px;
  }
  .tut-toc-hint--left {
    left: 3px;
    --hint-nudge: -3px;
  }
  .tut-toc-hint--show {
    opacity: 1;
    pointer-events: auto;
    cursor: pointer;
  }
}
@media (max-width: 833px) and (prefers-reduced-motion: reduce) {
  .tut-toc-hint {
    animation: none;
  }
}

.step-card {
  display: flex;
  gap: 16px;
}
.step-card__num {
  flex-shrink: 0;
  min-width: 26px;
  padding-top: 3px;
  font-size: 22px;
  line-height: 1.2;
  font-weight: 700;
  color: var(--text-3);
  font-variant-numeric: tabular-nums;
}
.step-card__body {
  flex: 1;
  min-width: 0;
}
.step-card h3 {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.01em;
}
.step-card p {
  color: var(--text-2);
  margin: 6px 0;
}
.step-card ul,
.step-card ol {
  color: var(--text-2);
  margin: 6px 0;
  padding-left: 20px;
}
.step-card li {
  margin: 4px 0;
}
.step-card li::marker {
  color: var(--text-3);
}
.step-card .tip {
  margin-top: 10px;
  padding-left: 12px;
  border-left: 2px solid var(--border-strong);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.01em;
  color: var(--text-3);
}
@media (max-width: 833px) {
  .step-card__num {
    display: none;
  }
}

.faq {
  background: var(--card-3);
  border-radius: var(--radius-sm);
  margin-bottom: 10px;
  overflow: hidden;
  transition: background-color 0.25s var(--ease);
}
.faq summary {
  display: flex;
  align-items: center;
  padding: 13px 16px;
  font-weight: 600;
  font-size: 14px;
  cursor: pointer;
  list-style: none;
  border-radius: var(--radius-sm);
  transition: background-color 0.2s var(--ease), border-radius 0.2s var(--ease);
}
.faq summary:hover {
  background: var(--faq-hover);
}
.faq summary::-webkit-details-marker {
  display: none;
}
.faq summary::before {
  content: "+";
  flex-shrink: 0;
  width: 18px;
  margin-right: 6px;
  text-align: center;
  line-height: 1;
  color: var(--text-3);
  font-weight: 600;
  transition: transform 0.25s var(--ease);
}
.faq[open] summary {
  background: var(--faq-hover);
  border-radius: var(--radius-sm);
}
.faq[open] summary::before {
  transform: rotate(45deg);
}
.faq.is-closing summary::before {
  transform: none;
}
.faq p {
  margin: 0;
  padding: 10px 16px 10px 40px;
  font-size: 13px;
  color: var(--text-2);
}

.ad-slot {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 120px;
  margin: 44px 0 0;
  border: 1px dashed var(--border-strong);
  border-radius: var(--radius);
  color: var(--text-3);
  font-size: 12px;
}

.page:has(> .ad-slot) {
  display: none;
}

.content-footer {
  border-top: 1px solid var(--border);
  margin-top: 16px;
  padding: 28px 24px 40px;
  text-align: center;
  font-size: 13px;
  color: var(--text-3);
}
.content-footer__links {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 6px 14px;
  margin-bottom: 12px;
}
.content-footer__links a {
  color: var(--text-2);
  text-decoration: none;
  transition: color 0.2s var(--ease);
}
.content-footer__links a:hover {
  color: var(--accent);
}
.content-footer__dot {
  color: var(--border-strong);
  user-select: none;
}