/* FreeRead 项目主页。视觉沿用应用的"纸张、墨色与陶土"（docs/adr/0007-paper-ink-clay-ui.md）：
   色阶照抄 apps/desktop/src/app/theme.ts，组件样式照抄 apps/desktop/src/styles/global.css。
   强调色只用于指认；主按钮用墨色；线条代替阴影；动效短、安静、不回弹。 */

@font-face {
  font-family: "IBM Plex Sans";
  font-weight: 400;
  font-display: swap;
  src: url(fonts/ibm-plex-sans-latin-400-normal.woff2) format("woff2");
}
@font-face {
  font-family: "IBM Plex Sans";
  font-weight: 500;
  font-display: swap;
  src: url(fonts/ibm-plex-sans-latin-500-normal.woff2) format("woff2");
}
@font-face {
  font-family: "IBM Plex Sans";
  font-weight: 600;
  font-display: swap;
  src: url(fonts/ibm-plex-sans-latin-600-normal.woff2) format("woff2");
}
@font-face {
  font-family: "IBM Plex Mono";
  font-weight: 400;
  font-display: swap;
  src: url(fonts/ibm-plex-mono-latin-400-normal.woff2) format("woff2");
}
@font-face {
  font-family: "IBM Plex Mono";
  font-weight: 500;
  font-display: swap;
  src: url(fonts/ibm-plex-mono-latin-500-normal.woff2) format("woff2");
}
@font-face {
  font-family: "Source Serif 4 Variable";
  font-weight: 200 900;
  font-display: swap;
  src: url(fonts/source-serif-4-latin-opsz-normal.woff2) format("woff2-variations");
}

/* ================================================================ 令牌 */

:root {
  --bg: #faf9f5;
  --bg2: #f0eee6;
  --surface: #ffffff;
  --ink: #141413;
  --ink2: #3d3d3a;
  --ink3: #65645e;
  --line: #e6e3da;
  --line2: #d4d0c4;
  --hover: rgba(20, 20, 19, 0.05);
  --ok: #3f6b45;
  --err: #a3402f;
  --btn: #141413;
  --btn-ink: #faf9f5;
  --page: #ffffff;
  --accent: #d97757;
  --accent-ink: color-mix(in oklab, var(--accent) 70%, #000);
  --accent-soft: color-mix(in srgb, var(--accent) 14%, transparent);

  --font-ui: "IBM Plex Sans", "Source Han Sans SC", "Noto Sans SC", "Noto Sans CJK SC", "PingFang SC",
    "Microsoft YaHei", system-ui, sans-serif;
  --font-serif: "Source Serif 4 Variable", "Source Serif 4", "Source Han Serif SC", "Noto Serif SC",
    "Noto Serif CJK SC", "Songti SC", "SimSun", Georgia, serif;
  --font-mono: "IBM Plex Mono", ui-monospace, "Cascadia Mono", Consolas, monospace;

  --dur-fast: 120ms;
  --dur: 200ms;
  --dur-slow: 280ms;
  /* 页面级的进场（整段内容滑入）比控件动效长，但用同一条缓动、不回弹 */
  --dur-page: 560ms;
  --ease: cubic-bezier(0.2, 0, 0, 1);
  --ease-exit: cubic-bezier(0.4, 0, 1, 1);

  --wrap: 1160px;
  --gutter: 24px;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #1f1e1d;
    --bg2: #262624;
    --surface: #30302e;
    --ink: #f3f1ea;
    --ink2: #d6d3c8;
    --ink3: #a6a398;
    --line: #3b3a37;
    --line2: #4c4a45;
    --hover: rgba(255, 255, 255, 0.06);
    --ok: #9cc79c;
    --err: #eba08c;
    --btn: #f3f1ea;
    --btn-ink: #1f1e1d;
    --page: #eceae3;
    --accent-ink: color-mix(in oklab, var(--accent) 62%, #fff);
    --accent-soft: color-mix(in srgb, var(--accent) 22%, transparent);
    color-scheme: dark;
  }
}

:root[data-theme="dark"] {
  --bg: #1f1e1d;
  --bg2: #262624;
  --surface: #30302e;
  --ink: #f3f1ea;
  --ink2: #d6d3c8;
  --ink3: #a6a398;
  --line: #3b3a37;
  --line2: #4c4a45;
  --hover: rgba(255, 255, 255, 0.06);
  --ok: #9cc79c;
  --err: #eba08c;
  --btn: #f3f1ea;
  --btn-ink: #1f1e1d;
  --page: #eceae3;
  --accent-ink: color-mix(in oklab, var(--accent) 62%, #fff);
  --accent-soft: color-mix(in srgb, var(--accent) 22%, transparent);
  color-scheme: dark;
}

/* ================================================================ 基础 */

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-ui);
  font-size: 15px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

a {
  color: inherit;
}

button {
  font: inherit;
  color: inherit;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

::selection {
  background: var(--accent-soft);
}

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

.wrap {
  width: 100%;
  max-width: calc(var(--wrap) + 2 * var(--gutter));
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.serif {
  font-family: var(--font-serif);
}

.mono {
  font-family: var(--font-mono);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.ico {
  flex: none;
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ================================================================ 应用里的基础组件（照抄） */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 40px;
  padding: 0 16px;
  border: 1px solid var(--line2);
  border-radius: 8px;
  background: var(--surface);
  color: var(--ink);
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition: border-color var(--dur-fast) var(--ease), background-color var(--dur-fast) var(--ease),
    color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}

.btn:hover {
  border-color: var(--ink3);
}

.btn:active {
  transform: scale(0.97);
}

.btn.lg {
  height: 46px;
  padding: 0 22px;
  font-size: 15px;
}

.btn.sm {
  height: 34px;
  padding: 0 12px;
  font-size: 13px;
}

.btn.primary {
  border-color: var(--btn);
  background: var(--btn);
  color: var(--btn-ink);
}

.btn.primary:hover {
  background: color-mix(in srgb, var(--btn) 86%, var(--bg));
}

.btn.ghost {
  border-color: transparent;
  background: none;
  color: var(--ink2);
}

.btn.ghost:hover {
  background: var(--hover);
  color: var(--ink);
}

.btn[aria-pressed="true"] {
  border-color: transparent;
  background: var(--accent-soft);
  color: var(--accent-ink);
}

.ibtn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: none;
  width: 38px;
  height: 38px;
  border: 0;
  border-radius: 8px;
  background: none;
  color: var(--ink2);
  text-decoration: none;
  cursor: pointer;
  transition: background-color var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease),
    transform var(--dur-fast) var(--ease);
}

.ibtn:hover {
  background: var(--hover);
  color: var(--ink);
}

.ibtn:active {
  transform: scale(0.97);
}

/* 分段控件：底块由 JS 量出位置后滑动（同 apps/desktop 的 Segmented） */
.seg {
  position: relative;
  display: inline-flex;
  gap: 2px;
  padding: 3px;
  border-radius: 9px;
  background: var(--hover);
}

.seg-thumb {
  position: absolute;
  top: 3px;
  left: 0;
  width: var(--seg-w, 0);
  height: calc(100% - 6px);
  border-radius: 7px;
  background: var(--surface);
  box-shadow: 0 1px 2px rgb(0 0 0 / 0.06), 0 0 0 1px var(--line);
  opacity: 0;
  transform: translateX(var(--seg-x, 0));
  transition: transform var(--dur) var(--ease), width var(--dur) var(--ease);
  pointer-events: none;
}

.seg[data-ready] .seg-thumb {
  opacity: 1;
}

.seg button {
  position: relative;
  height: 28px;
  padding: 0 11px;
  border: 0;
  border-radius: 7px;
  background: none;
  color: var(--ink2);
  font-size: 13px;
  white-space: nowrap;
  cursor: pointer;
  transition: color var(--dur-fast) var(--ease);
}

.seg button:hover {
  color: var(--ink);
}

.seg button[aria-pressed="true"],
.seg button[aria-selected="true"] {
  background: var(--surface);
  color: var(--ink);
  box-shadow: 0 1px 2px rgb(0 0 0 / 0.06), 0 0 0 1px var(--line);
}

.seg[data-ready] button[aria-pressed="true"],
.seg[data-ready] button[aria-selected="true"] {
  background: none;
  box-shadow: none;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 24px;
  padding: 0 9px;
  border: 1px solid var(--line);
  border-radius: 6px;
  color: var(--ink3);
  font-size: 12px;
  font-weight: 500;
  white-space: nowrap;
}

.tag[data-status="ready"] {
  color: var(--ok);
}

.tag[data-status="parsing"] {
  border-color: transparent;
  background: var(--accent-soft);
  color: var(--accent-ink);
}

.dot {
  width: 6px;
  height: 6px;
  flex: none;
  border-radius: 50%;
  background: currentColor;
}

.cite {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 19px;
  height: 19px;
  margin-left: 3px;
  padding: 0 5px;
  border: 0;
  border-radius: 5px;
  background: var(--accent-soft);
  color: var(--accent-ink);
  font: 600 11px/1 var(--font-mono);
  vertical-align: 2px;
  cursor: pointer;
  transition: background-color var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease),
    transform var(--dur-fast) var(--ease);
}

.cite:hover,
.cite.active {
  background: var(--accent);
  color: #fff;
}

.mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: none;
  width: 26px;
  height: 26px;
  border-radius: 7px;
  background: var(--accent);
  color: #fff;
  transition: background-color var(--dur) var(--ease);
}

.mark svg {
  width: 64%;
  height: 64%;
  fill: currentColor;
  stroke: currentColor;
  stroke-width: 1.2;
  stroke-linejoin: round;
}

.progress {
  position: relative;
  height: 4px;
  overflow: hidden;
  border-radius: 2px;
  background: var(--line);
}

.progress > i {
  position: absolute;
  inset: 0 auto 0 0;
  width: var(--p, 0%);
  border-radius: inherit;
  background: var(--accent);
  transition: width var(--dur-slow) var(--ease);
}

/* ================================================================ 顶栏 */

.top {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.top.stuck {
  border-bottom-color: var(--line);
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  -webkit-backdrop-filter: saturate(1.2) blur(12px);
  backdrop-filter: saturate(1.2) blur(12px);
}

.top-in {
  display: flex;
  align-items: center;
  gap: 20px;
  height: 64px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 19px;
  font-weight: 600;
  letter-spacing: -0.01em;
  text-decoration: none;
}

.top-nav {
  position: relative;
  display: flex;
  gap: 2px;
  margin-left: 12px;
}

.top-nav a {
  padding: 6px 12px;
  border-radius: 8px;
  color: var(--ink2);
  font-size: 14px;
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease), background-color var(--dur-fast) var(--ease);
}

.top-nav a:hover {
  background: var(--hover);
  color: var(--ink);
}

.top-nav a.on {
  color: var(--ink);
}

/* 当前段落的强调色短线，在导航项之间滑动 */
.nav-ind {
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 16px;
  height: 2px;
  border-radius: 1px;
  background: var(--accent);
  opacity: 0;
  transform: translateX(var(--x, 0));
  transition: transform var(--dur-slow) var(--ease), opacity var(--dur) var(--ease);
}

.top-nav[data-active] .nav-ind {
  opacity: 1;
}

.top-actions {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}

/* 站外链接放在右侧，不进 .top-nav（那里的链接都是页内锚点，驱动段落指示线） */
.top-link {
  padding: 6px 12px;
  border-radius: 8px;
  color: var(--ink2);
  font-size: 14px;
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease), background-color var(--dur-fast) var(--ease);
}

.top-link:hover {
  background: var(--hover);
  color: var(--ink);
}

.theme-btn .sun,
:root[data-theme="dark"] .theme-btn .moon {
  display: none;
}

:root[data-theme="dark"] .theme-btn .sun {
  display: block;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-btn .moon {
    display: none;
  }
  :root:not([data-theme="light"]) .theme-btn .sun {
    display: block;
  }
}

/* ================================================================ Hero */

.hero {
  position: relative;
  padding: 88px 0 0;
  text-align: center;
  overflow: hidden;
}

/* 极淡的纸张网格，越往下越淡 */
.hero::before {
  content: "";
  position: absolute;
  inset: -64px 0 auto;
  height: 760px;
  background-image: linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 48px 48px;
  background-position: center top;
  -webkit-mask-image: radial-gradient(ellipse 60% 70% at 50% 20%, #000 0%, transparent 72%);
  mask-image: radial-gradient(ellipse 60% 70% at 50% 20%, #000 0%, transparent 72%);
  opacity: 0.7;
  pointer-events: none;
}

.hero > * {
  position: relative;
}

.hero-mark {
  width: 64px;
  height: 64px;
  margin: 0 auto 28px;
  border-radius: 17px;
}

.hero h1 {
  margin: 0 auto;
  max-width: 14em;
  font-family: var(--font-serif);
  font-size: clamp(40px, 6.4vw, 76px);
  font-weight: 500;
  line-height: 1.12;
  letter-spacing: -0.02em;
}

.hero h1 .line {
  display: block;
}

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

.hero .lead {
  max-width: 34em;
  margin: 24px auto 0;
  color: var(--ink2);
  font-size: clamp(16px, 1.6vw, 18px);
  line-height: 1.7;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-top: 36px;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 6px 18px;
  margin-top: 20px;
  color: var(--ink3);
  font-size: 13px;
}

.hero-meta span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.hero-shot {
  margin-top: 64px;
  perspective: 1600px;
}

/* ================================================================ 截图窗口框 */

.frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line2);
  border-radius: 12px;
  background: var(--bg);
  box-shadow: 0 1px 2px rgb(20 20 19 / 0.04), 0 24px 64px -24px rgb(20 20 19 / 0.18);
}

.frame img {
  width: 100%;
  height: auto;
}

.shot-dark {
  display: none;
}

:root[data-theme="dark"] .shot-light {
  display: none;
}

:root[data-theme="dark"] .shot-dark {
  display: block;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .shot-light {
    display: none;
  }
  :root:not([data-theme="light"]) .shot-dark {
    display: block;
  }
}

.hero-shot .frame {
  transform-origin: 50% 0;
}

/* 截图进入视口时由微倾斜、略小过渡到平放（支持滚动驱动动画的浏览器） */
@supports (animation-timeline: view()) {
  .hero-shot .frame {
    animation: tilt-in linear both;
    animation-timeline: view();
    animation-range: entry 0% cover 42%;
  }
}

@keyframes tilt-in {
  from {
    transform: rotateX(14deg) scale(0.92) translateY(24px);
  }
  to {
    transform: none;
  }
}

/* ================================================================ 分段标题 */

.sec {
  padding: 136px 0 0;
}

.sec-head {
  max-width: 720px;
  margin: 0 auto 56px;
  text-align: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
  color: var(--accent-ink);
  font: 500 12px/1 var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.sec-head h2 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(30px, 4.2vw, 48px);
  font-weight: 500;
  line-height: 1.2;
  letter-spacing: -0.015em;
}

.sec-head p {
  margin: 16px auto 0;
  max-width: 36em;
  color: var(--ink2);
  font-size: 16px;
}

/* ================================================================ 滚动揭示 */

.rv {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity var(--dur-page) var(--ease), transform var(--dur-page) var(--ease);
  transition-delay: calc(var(--i, 0) * 80ms);
}

.rv.in {
  opacity: 1;
  transform: none;
}

/* 没有 JS 时直接显示 */
.no-js .rv {
  opacity: 1;
  transform: none;
}

/* Hero 首屏逐行进场 */
.hero .rv {
  transform: translateY(14px);
}

.hero h1 .line.rv {
  transform: translateY(0.4em);
}

/* ================================================================ 复刻的应用窗口 */

.win {
  --win-h: 600px;
  position: relative;
  display: flex;
  flex-direction: column;
  height: var(--win-h);
  overflow: hidden;
  border: 1px solid var(--line2);
  border-radius: 12px;
  background: var(--bg);
  color: var(--ink);
  font-size: 14px;
  line-height: 1.5;
  text-align: left;
  box-shadow: 0 1px 2px rgb(20 20 19 / 0.04), 0 24px 64px -28px rgb(20 20 19 / 0.2);
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}

.win * {
  transition-property: background-color, color, border-color, box-shadow, opacity, transform;
  transition-duration: var(--dur);
  transition-timing-function: var(--ease);
}

.win-bar {
  display: flex;
  flex: none;
  align-items: center;
  height: 34px;
  padding-left: 14px;
  border-bottom: 1px solid var(--line);
  background: var(--bg2);
  color: var(--ink3);
  font-size: 12px;
}

.win-bar .title {
  flex: 1;
}

.win-bar .wb {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 34px;
  color: var(--ink3);
}

.win-bar .wb .ico {
  width: 14px;
  height: 14px;
}

.win-body {
  display: flex;
  flex: 1;
  min-height: 0;
}

/* 60px 图标栏 / 248px 侧栏 */
.w-side {
  display: flex;
  flex: none;
  flex-direction: column;
  gap: 2px;
  width: 232px;
  padding: 14px 10px;
  border-right: 1px solid var(--line);
  background: var(--bg2);
}

.w-side.rail {
  align-items: center;
  width: 60px;
  gap: 6px;
  padding: 14px 10px;
}

.w-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 4px 8px 16px;
  font-size: 18px;
  font-weight: 600;
}

.w-side.rail .w-brand {
  padding: 0 0 10px;
}

.w-side.rail .mark {
  width: 30px;
  height: 30px;
  border-radius: 8px;
}

.w-nav {
  display: flex;
  align-items: center;
  gap: 10px;
  width: 100%;
  height: 36px;
  padding: 0 10px;
  border-radius: 8px;
  color: var(--ink2);
  font-size: 13.5px;
  white-space: nowrap;
}

.w-side.rail .w-nav {
  justify-content: center;
  width: 40px;
  height: 40px;
  padding: 0;
}

.w-nav.on {
  background: var(--surface);
  color: var(--ink);
  box-shadow: 0 0 0 1px var(--line);
}

.w-nav.on .ico {
  color: var(--accent-ink);
}

.w-nav .n {
  margin-left: auto;
  color: var(--ink3);
  font-size: 12px;
}

.w-label {
  padding: 14px 10px 6px;
  color: var(--ink3);
  font-size: 12px;
}

.w-nav.sub {
  padding-left: 30px;
}

.w-main {
  display: flex;
  flex: 1;
  flex-direction: column;
  min-width: 0;
}

.w-top {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 16px;
  border-bottom: 1px solid var(--line);
}

.w-top .t {
  flex: 1;
  min-width: 0;
}

.w-top h3 {
  margin: 0;
  overflow: hidden;
  font-size: 15.5px;
  font-weight: 500;
  line-height: 1.3;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.w-top .by {
  overflow: hidden;
  color: var(--ink3);
  font-size: 11.5px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.w-status {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--ink3);
  font-size: 12px;
  white-space: nowrap;
}

.w-status .dot {
  color: var(--ok);
}

.w-tools {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 8px 16px;
  border-bottom: 1px solid var(--line);
  white-space: nowrap;
}

.w-tools .grp {
  display: flex;
  align-items: center;
  gap: 6px;
}

.lbl {
  color: var(--ink3);
  font-size: 12px;
}

.w-tools .seg button {
  height: 24px;
  padding: 0 9px;
  font-size: 12px;
}

.w-tools .acts {
  display: flex;
  gap: 2px;
  margin-left: auto;
}

.w-tools .btn.sm {
  height: 30px;
  padding: 0 10px;
  gap: 6px;
  font-size: 12.5px;
}

.w-tools .btn .ico {
  width: 15px;
  height: 15px;
}

.slider {
  position: relative;
  width: 64px;
  height: 4px;
  border-radius: 2px;
  background: var(--line2);
}

.slider::before {
  content: "";
  position: absolute;
  inset: 0 50% 0 0;
  border-radius: inherit;
  background: var(--ink2);
}

.slider::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 12px;
  height: 12px;
  margin: -6px 0 0 -6px;
  border-radius: 50%;
  background: var(--surface);
  box-shadow: 0 0 0 1px var(--line2), 0 1px 2px rgb(0 0 0 / 0.12);
}

.w-panes,
.w-row {
  display: flex;
  flex: 1;
  min-width: 0;
  min-height: 0;
}

.w-tools {
  overflow: hidden;
}

.tour .w-pdf {
  flex: 0 0 34%;
}

.tour .w-panel {
  width: 272px;
}

.w-pane {
  position: relative;
  flex: 1;
  min-width: 0;
  overflow: hidden;
}

.w-pane + .w-pane {
  border-left: 1px solid var(--line);
}

/* 原版 PDF 页示意：白纸 + 灰色文字行 */
.w-pdf {
  padding: 18px;
  background: var(--bg2);
}

.page {
  position: relative;
  max-width: 340px;
  margin: 0 auto;
  padding: 22px 20px;
  border-radius: 4px;
  background: var(--page);
  box-shadow: 0 1px 3px rgb(20 20 19 / 0.08), 0 0 0 1px rgb(20 20 19 / 0.05);
  color: #141413;
}

.page .cols {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.pb {
  position: relative;
  margin-bottom: 10px;
  border-radius: 3px;
}

/* 文字行：用重复渐变画灰条 */
.pb .ln {
  height: var(--h, 34px);
  background: repeating-linear-gradient(
      to bottom,
      rgb(20 20 19 / 0.22) 0 3px,
      transparent 3px 7px
    )
    0 0 / 100% 7px;
}

.pb.t .ln {
  height: 16px;
  background: repeating-linear-gradient(to bottom, rgb(20 20 19 / 0.7) 0 6px, transparent 6px 10px);
  width: 86%;
}

.pb.a .ln {
  background-image: repeating-linear-gradient(to bottom, rgb(20 20 19 / 0.36) 0 3px, transparent 3px 7px);
}

.pb.au .ln {
  height: 4px;
  width: 60%;
}

.pb.fig {
  height: 58px;
  border-radius: 3px;
  background: linear-gradient(135deg, rgb(20 20 19 / 0.06), rgb(20 20 19 / 0.12));
}

.pb.fig::after {
  content: "";
  position: absolute;
  inset: 12px 18px;
  border-radius: 50%;
  border: 1.5px solid rgb(20 20 19 / 0.22);
  border-left-color: transparent;
}

.pb.eq {
  height: 14px;
  margin: 4px 18px 12px;
  background: repeating-linear-gradient(90deg, rgb(20 20 19 / 0.4) 0 8px, transparent 8px 11px);
  border-radius: 2px;
  -webkit-mask-image: linear-gradient(to bottom, transparent 4px, #000 4px, #000 10px, transparent 10px);
  mask-image: linear-gradient(to bottom, transparent 4px, #000 4px, #000 10px, transparent 10px);
}

/* 定位高亮（同应用 .pdf-highlight） */
.pb::before {
  content: "";
  position: absolute;
  inset: -4px -5px;
  border-radius: 4px;
  background: color-mix(in srgb, var(--accent) 16%, transparent);
  outline: 1.5px solid color-mix(in srgb, var(--accent) 55%, transparent);
  opacity: 0;
  transition: opacity var(--dur) var(--ease);
  pointer-events: none;
}

.pb.on::before {
  opacity: 1;
}

.pb.pulse::before {
  animation: locate-pulse 900ms var(--ease);
}

@keyframes locate-pulse {
  0% {
    opacity: 1;
    transform: scale(1.04);
  }
  100% {
    opacity: 1;
    transform: none;
  }
}

/* 重排正文 */
.w-reflow {
  padding: 22px 26px 40px;
  overflow: hidden;
  font-family: var(--font-serif);
  font-size: 15px;
  line-height: 1.68;
}

.rf {
  position: relative;
  margin: 0 -10px;
  padding: 4px 10px;
  border-radius: 8px;
  cursor: pointer;
}

.rf:hover {
  background: var(--hover);
}

.rf.located {
  background: var(--accent-soft);
}

.rf h4 {
  margin: 0 0 4px;
  font-size: 20px;
  font-weight: 600;
  line-height: 1.3;
}

.rf p {
  margin: 0 0 6px;
}

.rf .eq {
  padding: 4px 0;
  font-style: italic;
  text-align: center;
}

.rf .fig {
  display: grid;
  place-items: center;
  height: 64px;
  margin-bottom: 6px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--bg2);
  color: var(--ink3);
}

.rf .cap {
  color: var(--ink2);
  font-size: 13px;
}

.tr {
  color: var(--ink);
}

.pair[data-mode="side"] {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.pair[data-mode="alternate"] .tr {
  margin-top: -2px;
  color: var(--ink2);
  font-size: 0.94em;
}

.pair[data-mode="only"] .src {
  display: none;
}

.pair[data-mode="off"] .tr {
  display: none;
}

.caret {
  display: inline-block;
  width: 2px;
  height: 1em;
  margin-left: 1px;
  vertical-align: -2px;
  background: var(--accent);
  animation: blink 1s steps(1) infinite;
}

@keyframes blink {
  50% {
    opacity: 0;
  }
}

/* 右侧面板 */
.w-panel {
  display: flex;
  flex: none;
  flex-direction: column;
  width: 300px;
  min-height: 0;
  border-left: 1px solid var(--line);
  background: var(--bg);
}

.w-panel-head {
  display: flex;
  align-items: center;
  padding: 12px 16px 6px 20px;
}

.w-panel-head h5 {
  flex: 1;
  margin: 0;
  font-size: 17px;
  font-weight: 500;
}

.w-panel-head .ico {
  color: var(--ink3);
}

.qa-msgs {
  display: flex;
  flex: 1;
  flex-direction: column;
  gap: 14px;
  min-height: 0;
  padding: 8px 20px 12px;
  overflow: hidden;
}

.qa-q {
  align-self: flex-end;
  max-width: 88%;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--bg2);
  font-size: 13px;
}

.qa-a {
  font-family: var(--font-serif);
  font-size: 14px;
  line-height: 1.7;
}

.composer {
  margin: 0 12px 12px;
  padding: 10px 10px 8px 14px;
  border: 1px solid var(--line2);
  border-radius: 16px;
  background: var(--surface);
  box-shadow: 0 1px 2px rgb(20 20 19 / 0.04), 0 4px 16px rgb(20 20 19 / 0.04);
}

.composer .ph {
  min-height: 34px;
  color: var(--ink3);
  font-size: 13px;
}

.composer .ft {
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--ink3);
  font-size: 11.5px;
}

.send {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  border-radius: 9px;
  background: var(--btn);
  color: var(--btn-ink);
}

.send .ico {
  width: 15px;
  height: 15px;
}

/* 底部任务栏 */
.w-jobs {
  display: flex;
  flex: none;
  align-items: center;
  gap: 14px;
  height: 36px;
  padding: 0 16px;
  border-top: 1px solid var(--line);
  color: var(--ink2);
  font-size: 12px;
}

.w-jobs .progress {
  width: 120px;
}

.w-jobs .cnt {
  margin-left: auto;
  color: var(--ink3);
}

/* ================================================================ 导览 */

.tour {
  display: grid;
  grid-template-columns: 300px 1fr;
  gap: 28px;
  align-items: center;
}

.tour-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.callout {
  display: flex;
  gap: 14px;
  width: 100%;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: none;
  text-align: left;
  cursor: pointer;
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.callout:hover {
  border-color: var(--line2);
}

.callout[aria-pressed="true"] {
  border-color: color-mix(in srgb, var(--accent) 45%, var(--line));
  background: var(--surface);
}

.callout .ci {
  display: grid;
  flex: none;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 9px;
  background: var(--hover);
  color: var(--ink2);
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.callout[aria-pressed="true"] .ci {
  background: var(--accent-soft);
  color: var(--accent-ink);
}

.callout b {
  display: block;
  font-size: 15px;
  font-weight: 500;
}

.callout span {
  display: block;
  margin-top: 2px;
  color: var(--ink3);
  font-size: 13px;
  line-height: 1.55;
}

/* 导览自动轮播的进度细线 */
.callout {
  position: relative;
  overflow: hidden;
}

.callout::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  height: 2px;
  width: 100%;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: 0 50%;
}

.tour.auto .callout[aria-pressed="true"]::after {
  animation: fill var(--tour-ms, 4200ms) linear forwards;
}

@keyframes fill {
  to {
    transform: scaleX(1);
  }
}

/* 被指认的窗口区域 */
[data-zone] {
  position: relative;
}

[data-zone]::after {
  content: "";
  position: absolute;
  inset: 3px;
  z-index: 5;
  border-radius: 8px;
  background: color-mix(in srgb, var(--accent) 7%, transparent);
  outline: 1.5px solid color-mix(in srgb, var(--accent) 65%, transparent);
  opacity: 0;
  transition: opacity var(--dur-slow) var(--ease);
  pointer-events: none;
}

[data-zone].zone-on::after {
  opacity: 1;
}

.win.zoning .w-pane,
.win.zoning .w-side,
.win.zoning .w-tools,
.win.zoning .w-panel {
  transition: opacity var(--dur-slow) var(--ease);
}

.win.zoning [data-zone]:not(.zone-on):not(:has(.zone-on)) {
  opacity: 0.55;
}

/* ================================================================ 编号演示 */

.steps-tabs {
  display: flex;
  justify-content: center;
  margin-bottom: 28px;
}

.steps-tabs .seg button {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 36px;
  padding: 0 14px;
  font-size: 14px;
}

.steps-tabs .seg .num {
  color: var(--ink3);
  font: 500 11px/1 var(--font-mono);
}

.steps-tabs .seg button[aria-selected="true"] .num {
  color: var(--accent-ink);
}

.stage {
  position: relative;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--bg2);
}

.step {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 40px;
  align-items: center;
  padding: 44px;
}

.step[hidden] {
  display: none;
}

.step.enter .step-text,
.step.enter .step-demo {
  animation: rise-in var(--dur-page) var(--ease) both;
}

.step.enter .step-demo {
  animation-delay: 80ms;
}

@keyframes rise-in {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
}

.step-text .n {
  color: var(--accent-ink);
  font: 500 13px/1 var(--font-mono);
}

.step-text h3 {
  margin: 12px 0 10px;
  font-family: var(--font-serif);
  font-size: 30px;
  font-weight: 500;
  line-height: 1.25;
}

.step-text p {
  margin: 0;
  color: var(--ink2);
}

.facts {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: 24px;
}

.fact {
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--bg);
}

.fact b {
  display: block;
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 500;
  line-height: 1.2;
}

.fact span {
  color: var(--ink3);
  font-size: 12.5px;
}

.step-demo .win {
  --win-h: 440px;
}

.demo-note {
  margin: 14px 0 0;
  color: var(--ink3);
  font-size: 12px;
  text-align: center;
}

/* 01 重排：重排块按顺序浮现 */
.rf.pending {
  opacity: 0;
  transform: translateY(8px);
}

.rf {
  transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease),
    background-color var(--dur) var(--ease);
}

/* 04 解析引擎 */
.engines {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 18px;
}

.engine {
  display: grid;
  grid-template-columns: 36px 1fr auto;
  gap: 4px 14px;
  align-items: center;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
}

.engine .ei {
  display: grid;
  grid-row: span 2;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 9px;
  background: var(--hover);
  color: var(--ink2);
  font: 600 12px/1 var(--font-mono);
}

.engine b {
  font-size: 14px;
  font-weight: 500;
}

.engine small {
  grid-column: 2;
  color: var(--ink3);
  font-size: 12px;
}

.engine .tag {
  grid-row: span 2;
  grid-column: 3;
}

.engine .progress {
  grid-column: 2 / 4;
  margin-top: 8px;
}

/* ================================================================ 定制 */

.custom {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 28px;
  align-items: start;
}

.custom .win {
  --win-h: 520px;
}

.appear {
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
}

.appear h3 {
  margin: 0 0 4px;
  font-size: 17px;
  font-weight: 500;
}

.appear > p {
  margin: 0 0 18px;
  color: var(--ink3);
  font-size: 13px;
}

.fld {
  padding: 14px 0;
  border-top: 1px solid var(--line);
}

.fld > span {
  display: block;
  margin-bottom: 10px;
  color: var(--ink2);
  font-size: 13px;
}

.swatches {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.sw {
  position: relative;
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: var(--c);
  cursor: pointer;
  transition: transform var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
}

.sw:hover {
  transform: scale(1.06);
}

.sw[aria-pressed="true"] {
  box-shadow: 0 0 0 2px var(--surface), 0 0 0 4px var(--c);
}

.sw svg {
  width: 16px;
  height: 16px;
  fill: none;
  stroke: #fff;
  stroke-width: 2.2;
  opacity: 0;
  transition: opacity var(--dur-fast) var(--ease);
}

.sw[aria-pressed="true"] svg {
  opacity: 1;
}

.sw-name {
  margin-top: 8px;
  color: var(--ink3);
  font-size: 12px;
}

/* 文献列表 */
.w-lib {
  flex: 1;
  min-width: 0;
  padding: 22px 26px 0;
  overflow: hidden;
}

.w-lib h3 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 26px;
  font-weight: 500;
}

.w-lib .sub {
  color: var(--ink3);
  font-size: 12.5px;
}

.w-lib-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
}

.w-search {
  display: flex;
  align-items: center;
  gap: 8px;
  height: 36px;
  margin-bottom: 8px;
  padding: 0 12px;
  border: 1px solid var(--line2);
  border-radius: 8px;
  background: var(--surface);
  color: var(--ink3);
  font-size: 13px;
}

.w-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 11px 4px;
  border-bottom: 1px solid var(--line);
}

.w-item.on {
  margin: 0 -10px;
  padding: 11px 14px;
  border-radius: 8px;
  border-bottom-color: transparent;
  background: var(--accent-soft);
}

.w-item .it {
  flex: 1;
  min-width: 0;
}

.w-item b {
  display: block;
  overflow: hidden;
  font-family: var(--font-serif);
  font-size: 15px;
  font-weight: 500;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.w-item small {
  display: block;
  overflow: hidden;
  color: var(--ink3);
  font-size: 12px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ================================================================ 截图墙 */

.gallery {
  display: flex;
  gap: 20px;
  padding: 4px var(--gutter) 24px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  scrollbar-width: thin;
  scrollbar-color: var(--line2) transparent;
}

@media (min-width: 1208px) {
  .gallery {
    padding-left: calc((100vw - var(--wrap)) / 2);
    padding-right: calc((100vw - var(--wrap)) / 2);
  }
}

.gallery figure {
  flex: none;
  width: min(760px, 84vw);
  margin: 0;
  scroll-snap-align: center;
}

.gallery button {
  display: block;
  width: 100%;
  padding: 0;
  border: 0;
  background: none;
  cursor: zoom-in;
}

.gallery figcaption {
  display: flex;
  gap: 10px;
  margin-top: 12px;
  color: var(--ink2);
  font-size: 14px;
}

.gallery figcaption b {
  font-weight: 500;
  color: var(--ink);
}

.gallery-nav {
  display: flex;
  justify-content: flex-end;
  gap: 6px;
  margin-top: -36px;
  margin-bottom: 16px;
}

.ibtn.bordered {
  border: 1px solid var(--line2);
}

.lightbox {
  width: min(1440px, 94vw);
  max-width: none;
  max-height: 94vh;
  padding: 0;
  border: 1px solid var(--line2);
  border-radius: 12px;
  background: var(--bg);
  overflow: hidden;
}

.lightbox::backdrop {
  background: rgb(20 20 19 / 0.5);
}

.lightbox[open] {
  animation: rise-in var(--dur-slow) var(--ease);
}

.lightbox img {
  width: 100%;
  height: auto;
}

.lightbox .ibtn {
  position: absolute;
  top: 10px;
  right: 10px;
  background: var(--surface);
  box-shadow: 0 0 0 1px var(--line);
}

/* ================================================================ 本地优先 */

.cards3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.card {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
}

.card .ci {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  margin-bottom: 18px;
  border-radius: 10px;
  background: var(--hover);
  color: var(--ink2);
}

.card h3 {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 500;
}

.card p {
  margin: 0;
  color: var(--ink2);
  font-size: 14px;
}

.features {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--line);
}

.feature {
  padding: 22px;
  background: var(--bg);
  transition: background-color var(--dur) var(--ease);
}

.feature:hover {
  background: var(--surface);
}

.feature .ico {
  width: 20px;
  height: 20px;
  color: var(--accent-ink);
}

.feature h3 {
  margin: 14px 0 6px;
  font-size: 15px;
  font-weight: 500;
}

.feature p {
  margin: 0;
  color: var(--ink3);
  font-size: 13.5px;
  line-height: 1.6;
}

/* ================================================================ 下载 */

.dl {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  max-width: 880px;
  margin: 0 auto;
}

.dl .card {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.dl .card h3 {
  display: flex;
  align-items: center;
  gap: 10px;
}

.dl .card .file {
  color: var(--ink3);
  font: 12.5px/1.5 var(--font-mono);
  overflow-wrap: anywhere;
}

.dl .card p {
  flex: 1;
  margin: 8px 0 18px;
}

.rec {
  height: 22px;
  padding: 0 8px;
  border-radius: 6px;
  background: var(--accent-soft);
  color: var(--accent-ink);
  font-size: 12px;
  font-weight: 500;
  line-height: 22px;
}

.dl-note {
  max-width: 880px;
  margin: 16px auto 0;
  color: var(--ink3);
  font-size: 13px;
  text-align: center;
}

.quick {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  max-width: 880px;
  margin: 56px auto 0;
  padding: 0;
  list-style: none;
  counter-reset: q;
}

.quick li {
  counter-increment: q;
  color: var(--ink2);
  font-size: 14px;
}

.quick li::before {
  content: "0" counter(q);
  display: block;
  margin-bottom: 10px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  color: var(--accent-ink);
  font: 500 12px/1 var(--font-mono);
}

.quick b {
  color: var(--ink);
  font-weight: 500;
}

/* ================================================================ 页脚 */

.foot {
  margin-top: 136px;
  padding: 40px 0 56px;
  border-top: 1px solid var(--line);
  color: var(--ink3);
  font-size: 13px;
}

.foot-in {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px 28px;
}

.foot nav {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 20px;
  margin-left: auto;
}

.foot a {
  text-decoration: none;
}

.foot a:hover {
  color: var(--ink);
}

.closing {
  margin-top: 136px;
  text-align: center;
}

.closing h2 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(30px, 4.6vw, 54px);
  font-weight: 500;
  line-height: 1.2;
}

.closing .hero-cta {
  margin-top: 28px;
}

/* ================================================================ 窄屏 */

@media (max-width: 1080px) {
  .tour,
  .custom {
    grid-template-columns: 1fr;
  }
  .tour-list {
    flex-direction: row;
    overflow-x: auto;
    scrollbar-width: none;
  }
  .callout {
    flex: none;
    width: 240px;
  }
  .step {
    grid-template-columns: 1fr;
    padding: 28px;
  }
  .features {
    grid-template-columns: repeat(2, 1fr);
  }
  .w-panel {
    width: 260px;
  }
}

@media (max-width: 860px) {
  .top-nav {
    display: none;
  }
  .w-pdf {
    display: none;
  }
  .w-side:not(.rail) {
    display: none;
  }
}

@media (max-width: 720px) {
  :root {
    --gutter: 16px;
  }
  .sec {
    padding-top: 96px;
  }
  .hero {
    padding-top: 56px;
  }
  .hero-shot {
    margin-top: 44px;
  }
  .cards3,
  .dl,
  .quick {
    grid-template-columns: 1fr;
  }
  .features {
    grid-template-columns: 1fr;
  }
  .steps-tabs {
    overflow-x: auto;
    scrollbar-width: none;
  }
  .steps-tabs .seg .txt {
    display: none;
  }
  .step {
    padding: 20px 16px;
  }
  .facts {
    grid-template-columns: 1fr 1fr;
  }
  .win {
    --win-h: 520px;
  }
  .w-side.rail,
  .w-panel,
  .w-tools .acts,
  .w-tools .grp.size {
    display: none;
  }
  .tour .win .w-panel {
    display: none;
  }
  .step-demo .w-panel {
    display: flex;
    width: 100%;
    border-left: 0;
  }
  .pair[data-mode="side"] {
    grid-template-columns: 1fr;
    gap: 2px;
  }
  .w-top .w-status {
    display: none;
  }
  .gallery-nav {
    display: none;
  }
  .foot nav {
    margin-left: 0;
  }
  .btn.dl-top .txt {
    display: none;
  }
}

/* ================================================================ 减少动效 */

@media (prefers-reduced-motion: reduce) {
  :root {
    --dur-fast: 0ms;
    --dur: 0ms;
    --dur-slow: 0ms;
    --dur-page: 0ms;
  }
  html {
    scroll-behavior: auto;
  }
  .rv {
    opacity: 1;
    transform: none;
  }
  .hero-shot .frame {
    animation: none !important;
  }
  .caret,
  .tour.auto .callout[aria-pressed="true"]::after {
    animation: none;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0ms !important;
    transition-duration: 0ms !important;
  }
}

.tour .grp.size {
  display: none;
}