/* dyz-gongwen-skills 落地页样式
   设计思路：页面本身按公文的样子组织（版头、红线、一二三四的章节序号、落款式页脚），
   用一红一墨两种颜色加整块色面分区，不用渐变、阴影、图标卡片等装饰。
   字号只用五级：small / body / lead / head / display。 */

:root {
  color-scheme: light dark;

  --ground: #f6f6f4;
  --surface: #ecece8;
  --surface-2: #e1e1dc;
  --ink: #18181a;
  --ink-soft: #4b4b51;
  --accent: #b3262d;
  --on-accent: #ffffff;
  --mark: rgba(179, 38, 45, 0.14);
  --focus: #1a5fd0;

  --code-bg: #1c1c1f;
  --code-ink: #ececea;
  --code-soft: #a3a3a9;

  --field-red: #a8232a;
  --field-red-ink: #ffffff;
  --field-red-soft: rgba(255, 255, 255, 0.8);
  --field-red-line: rgba(255, 255, 255, 0.28);

  --paper: #ffffff;
  --paper-ink: #1a1a1a;
  --paper-red: #e60012;

  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, sans-serif;

  --fs-small: clamp(0.875rem, 0.85rem + 0.1vw, 0.9375rem);
  --fs-body: clamp(1.0625rem, 1.02rem + 0.18vw, 1.125rem);
  --fs-lead: clamp(1.25rem, 1.05rem + 0.9vw, 1.75rem);
  --fs-head: clamp(1.875rem, 1.2rem + 2.9vw, 3.5rem);
  --fs-display: clamp(3.25rem, 1.6rem + 7vw, 7.75rem);

  --margin: clamp(16px, 4vw, 40px);
  --maxw: 1320px;
  --gap-sec: clamp(72px, 9vw, 128px);
  --radius: 2px;
  --ease: cubic-bezier(0.22, 0.8, 0.24, 1);
  --header-h: 60px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --ground: #131315;
    --surface: #1c1c1f;
    --surface-2: #27272b;
    --ink: #ececea;
    --ink-soft: #a9a9ae;
    --accent: #ef6a6f;
    --on-accent: #131315;
    --mark: rgba(239, 106, 111, 0.24);
    --focus: #7fb0ff;

    --code-bg: #0c0c0e;
    --code-ink: #ececea;
    --code-soft: #8d8d93;

    --field-red: #6c1a20;
    --field-red-ink: #f6eeee;
    --field-red-soft: rgba(246, 238, 238, 0.78);
    --field-red-line: rgba(246, 238, 238, 0.26);
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-padding-top: calc(var(--header-h) + 16px);
}

@media (prefers-reduced-motion: no-preference) {
  html {
    scroll-behavior: smooth;
  }
}

body {
  margin: 0;
  background: var(--ground);
  color: var(--ink);
  font-family: var(--sans);
  font-size: var(--fs-body);
  font-weight: 400;
  line-height: 1.85;
  letter-spacing: 0.012em;
  line-break: strict;
  word-break: auto-phrase;
  text-autospace: normal;
  text-spacing-trim: space-first;
  hanging-punctuation: first allow-end;
  overflow-wrap: break-word;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
}

h1,
h2,
h3 {
  margin: 0;
  font-family: var(--serif);
  font-weight: 700;
  letter-spacing: 0.01em;
  text-wrap: balance;
  word-break: auto-phrase;
}

p,
ul,
ol,
dl,
dd,
figure,
blockquote {
  margin: 0;
}

p {
  text-wrap: pretty;
}

ul,
ol {
  padding: 0;
  list-style: none;
}

a {
  color: inherit;
  text-decoration-line: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.22em;
  text-decoration-color: color-mix(in srgb, currentColor 40%, transparent);
  transition: text-decoration-color 0.2s var(--ease), color 0.2s var(--ease);
}

a:hover {
  text-decoration-color: currentColor;
  color: var(--accent);
}

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

::selection {
  background: var(--accent);
  color: var(--on-accent);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}

.skip {
  position: absolute;
  left: var(--margin);
  top: -80px;
  z-index: 100;
  background: var(--accent);
  color: var(--on-accent);
  padding: 8px 16px;
  text-decoration: none;
  transition: top 0.2s var(--ease);
}

.skip:focus {
  top: 8px;
  color: var(--on-accent);
}

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

.small {
  font-size: var(--fs-small);
  line-height: 1.75;
}

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

/* ---------- 按钮 ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 52px;
  padding: 10px 28px;
  border: 0;
  border-radius: var(--radius);
  font: inherit;
  font-weight: 500;
  letter-spacing: 0.04em;
  line-height: 1.2;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.2s var(--ease), background-color 0.2s var(--ease), color 0.2s var(--ease);
}

.btn-primary {
  background: var(--accent);
  color: var(--on-accent);
}

.btn-primary:hover {
  color: var(--on-accent);
  background: color-mix(in srgb, var(--accent) 86%, var(--ink));
  transform: translateY(-2px);
}

.btn-quiet {
  background: var(--surface-2);
  color: var(--ink);
}

.btn-quiet:hover {
  color: var(--ink);
  background: color-mix(in srgb, var(--surface-2) 80%, var(--ink));
  transform: translateY(-2px);
}

.btn:active {
  transform: translateY(0) scale(0.98);
}

.btn .arrow {
  display: inline-block;
  transition: transform 0.25s var(--ease);
}

.btn:hover .arrow {
  transform: translateX(4px);
}

/* ---------- 顶栏 ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--ground);
  transition: background-color 0.3s var(--ease);
}

.site-header.is-scrolled {
  background: var(--surface);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: var(--header-h);
}

.brand {
  display: inline-flex;
  align-items: baseline;
  gap: 10px;
  text-decoration: none;
  font-family: var(--serif);
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: 0.02em;
  color: var(--ink);
  white-space: nowrap;
}

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

.brand-mark {
  display: inline-block;
  width: 0.62em;
  height: 0.62em;
  background: var(--accent);
  border-radius: 1px;
  align-self: center;
  transition: transform 0.35s var(--ease);
}

.brand:hover .brand-mark {
  transform: rotate(90deg);
}

.nav-links {
  display: none;
  gap: clamp(16px, 2.4vw, 36px);
  font-size: var(--fs-small);
}

.nav-links a {
  text-decoration: none;
  padding: 6px 0;
  position: relative;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform 0.3s var(--ease);
}

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

.nav-links a:hover::after {
  transform: scaleX(1);
}

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

.nav-actions .btn {
  min-height: 40px;
  padding: 6px 16px;
  font-size: var(--fs-small);
}

@media (min-width: 860px) {
  .nav-links {
    display: flex;
  }
}

/* ---------- 首屏 ---------- */

.hero {
  padding-block: clamp(40px, 6vw, 88px) var(--gap-sec);
}

.hero-grid {
  display: grid;
  gap: clamp(40px, 6vw, 72px);
  grid-template-columns: minmax(0, 1fr);
  align-items: start;
}

.hero h1 {
  font-size: var(--fs-display);
  line-height: 1.04;
  letter-spacing: -0.01em;
  font-weight: 800;
}

.hero h1 .latin {
  display: block;
  color: var(--accent);
  letter-spacing: -0.02em;
}

.hero-copy .lead {
  margin-top: clamp(24px, 3vw, 40px);
  font-family: var(--serif);
  font-weight: 600;
  font-size: var(--fs-lead);
  line-height: 1.6;
  max-width: 24em;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(28px, 3.5vw, 44px);
}

.hero-tools {
  margin-top: clamp(28px, 3.5vw, 48px);
  color: var(--ink-soft);
  max-width: 36em;
}

.sheet-wrap {
  position: relative;
}

/* 红头文件示意：真实 A4 比例，内文取自 examples/B-AI稿体检 的成稿 */

.sheet {
  container-type: inline-size;
  position: relative;
  width: 100%;
  max-width: 460px;
  margin-inline: auto;
  aspect-ratio: 210 / 297;
  background: var(--paper);
  color: var(--paper-ink);
  overflow: hidden;
  box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.06), 0 18px 40px rgba(0, 0, 0, 0.12);
  transform: rotate(0.6deg);
  transition: transform 0.6s var(--ease);
}

.sheet:hover {
  transform: rotate(0deg) translateY(-4px);
}

.sheet-in {
  padding: 9cqw 10cqw;
  font-family: var(--serif);
  font-weight: 400;
  font-size: 3.1cqw;
  line-height: 1.75;
  letter-spacing: 0;
}

.sheet * {
  letter-spacing: 0;
}

.sheet-head {
  text-align: center;
  color: var(--paper-red);
  font-family: var(--serif);
  font-weight: 700;
  font-size: 7.4cqw;
  line-height: 1.2;
}

.sheet-no {
  margin-top: 4.6cqw;
  text-align: center;
  font-size: 3.2cqw;
}

.sheet-red {
  height: 0.5cqw;
  min-height: 2px;
  margin: 2cqw 0 7cqw;
  background: var(--paper-red);
}

.sheet-title {
  text-align: center;
  font-family: var(--serif);
  font-weight: 700;
  font-size: 4.9cqw;
  line-height: 1.5;
  margin-bottom: 5cqw;
}

.sheet p {
  text-indent: 2em;
  text-align: justify;
  margin-top: 0.4em;
}

.sheet .to {
  text-indent: 0;
}

.sheet .h {
  font-family: var(--sans);
  font-weight: 700;
  text-indent: 2em;
  margin-top: 0.9em;
}

/* ---------- 数字带 ---------- */

.figures {
  background: var(--surface);
  padding-block: clamp(48px, 6vw, 88px);
}

.fig-grid {
  display: grid;
  gap: clamp(28px, 4vw, 48px) clamp(20px, 3vw, 40px);
  grid-template-columns: minmax(0, 1fr);
}

.fig-num {
  font-family: var(--serif);
  font-weight: 800;
  font-size: calc(var(--fs-head) * 1.35);
  line-height: 1;
  color: var(--accent);
  letter-spacing: -0.02em;
  font-variant-numeric: lining-nums tabular-nums;
}

.fig-num small {
  font-size: 0.42em;
  font-weight: 700;
  margin-left: 0.15em;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.fig-label {
  margin-top: 14px;
  font-size: var(--fs-small);
  line-height: 1.7;
  color: var(--ink);
}

.fig-note {
  margin-top: clamp(28px, 3.5vw, 48px);
  max-width: 64em;
  color: var(--ink-soft);
}

@media (min-width: 640px) {
  .fig-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1040px) {
  .fig-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 章节通用 ---------- */

.sec {
  padding-block: var(--gap-sec);
}

.sec-tint {
  background: var(--surface);
}

.sec h2 {
  font-size: var(--fs-head);
  line-height: 1.3;
}

.sec h2 .num {
  color: inherit;
  margin-right: -0.32em;
}

.sec-grid {
  display: grid;
  gap: clamp(32px, 5vw, 64px);
  grid-template-columns: minmax(0, 1fr);
}

.lede {
  margin-top: 20px;
  max-width: 38em;
  color: var(--ink-soft);
}

@media (min-width: 960px) {
  .sec-grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
  }

  .diff-head {
    grid-column: 1 / span 4;
  }

  .diff-body {
    grid-column: 5 / span 8;
    margin-top: -24px;
  }

  .hero-layout {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    column-gap: clamp(32px, 5vw, 80px);
  }
}

/* ---------- 和普通 AI 的不同：对照表 ---------- */

.diff-grid {
  margin-top: clamp(24px, 3vw, 40px);
}

.diff-head .lede {
  margin-top: 0;
}

.diff-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0 8px;
  font-size: var(--fs-body);
  line-height: 1.7;
}

.diff-table th,
.diff-table td {
  text-align: left;
  vertical-align: top;
  padding: 16px 18px;
  font-weight: 400;
}

.diff-table thead th {
  padding-block: 4px 8px;
  font-family: var(--serif);
  font-size: var(--fs-small);
  color: var(--ink-soft);
  font-weight: 700;
}

.diff-table thead th:last-child {
  color: var(--accent);
}

.diff-table tbody th {
  width: 18%;
  font-family: var(--serif);
  font-weight: 700;
  background: var(--surface);
  white-space: nowrap;
}

.diff-table tbody td {
  background: var(--surface);
  color: var(--ink-soft);
}

.diff-table tbody td:last-child {
  background: var(--surface-2);
  color: var(--ink);
  font-weight: 500;
}

@media (max-width: 719px) {
  .diff-table,
  .diff-table tbody,
  .diff-table tr,
  .diff-table th,
  .diff-table td {
    display: block;
    width: 100%;
  }

  .diff-table thead {
    display: none;
  }

  .diff-table tbody tr {
    margin-bottom: 12px;
  }

  .diff-table tbody th {
    width: 100%;
    padding-bottom: 6px;
  }

  .diff-table tbody td {
    padding-block: 10px;
  }

  .diff-table tbody td::before {
    display: block;
    font-size: var(--fs-small);
    font-weight: 700;
    margin-bottom: 2px;
    color: var(--ink-soft);
  }

  .diff-table tbody td:nth-of-type(1)::before {
    content: "一般的 AI 写作";
  }

  .diff-table tbody td:nth-of-type(2)::before {
    content: "dyz-gongwen-skills";
    color: var(--accent);
  }
}

/* ---------- 六条红线 ---------- */

.rules-grid {
  display: grid;
  gap: clamp(28px, 4vw, 48px) clamp(24px, 4vw, 64px);
  grid-template-columns: minmax(0, 1fr);
  margin-top: clamp(36px, 5vw, 64px);
}

.rule h3 {
  font-size: var(--fs-lead);
  line-height: 1.4;
}

.rule p {
  margin-top: 10px;
  color: var(--ink-soft);
}

.rules-foot {
  margin-top: clamp(32px, 4vw, 56px);
  color: var(--ink-soft);
}

@media (min-width: 760px) {
  .rules-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1100px) {
  .rules-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 前后对比 ---------- */

.delta {
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin-top: clamp(28px, 4vw, 48px);
}

.delta > div {
  background: var(--surface);
  padding: 18px 20px;
}

.delta dt {
  font-size: var(--fs-small);
  color: var(--ink-soft);
}

.delta dd {
  margin-top: 4px;
  font-family: var(--serif);
  font-weight: 800;
  font-size: var(--fs-lead);
  line-height: 1.35;
  font-variant-numeric: lining-nums tabular-nums;
}

.delta dd .to {
  color: var(--accent);
}

.delta dd .to.block {
  display: block;
}

@media (max-width: 899px) {
  .delta > div:last-child {
    grid-column: 1 / -1;
  }
}

@media (min-width: 900px) {
  .delta {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.cmp {
  display: grid;
  gap: 16px;
  grid-template-columns: minmax(0, 1fr);
  margin-top: 16px;
}

.cmp-card {
  padding: clamp(22px, 3vw, 36px);
  background: var(--surface);
}

.cmp-card.after {
  background: var(--surface-2);
}

.cmp-card h3 {
  font-size: var(--fs-lead);
  line-height: 1.4;
  margin-bottom: 14px;
}

.cmp-card.after h3 {
  color: var(--accent);
}

.cmp-card p + p {
  margin-top: 12px;
}

.cmp-card .doc-title {
  font-weight: 700;
}

.cmp-card mark {
  background: var(--mark);
  color: inherit;
  padding: 1px 3px;
  border-bottom: 2px solid var(--accent);
}

.legend {
  margin-top: 16px;
  color: var(--ink-soft);
}

.legend mark {
  background: var(--mark);
  color: inherit;
  padding: 1px 3px;
  border-bottom: 2px solid var(--accent);
}

.changes {
  margin-top: clamp(28px, 4vw, 48px);
  display: grid;
  gap: 14px;
  max-width: 52em;
}

.changes h3 {
  font-size: var(--fs-lead);
  margin-bottom: 4px;
}

.changes li {
  padding-left: 1.2em;
  position: relative;
}

.changes li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.8em;
  width: 0.5em;
  height: 0.5em;
  background: var(--accent);
}

.more-links {
  margin-top: clamp(28px, 4vw, 44px);
  display: flex;
  flex-wrap: wrap;
  gap: 12px 28px;
}

@media (min-width: 900px) {
  .cmp {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ---------- 22 个 skill ---------- */

.skill-group {
  display: grid;
  gap: 20px;
  grid-template-columns: minmax(0, 1fr);
  padding-block: clamp(32px, 4.5vw, 56px);
}

.skill-group + .skill-group {
  margin-top: 0;
}

.skill-group.tint {
  background: var(--surface);
}

.group-title {
  font-size: var(--fs-lead);
  line-height: 1.35;
}

.group-title .count {
  display: block;
  margin-top: 6px;
  font-family: var(--sans);
  font-weight: 400;
  font-size: var(--fs-small);
  color: var(--ink-soft);
}

.group-note {
  margin-top: 10px;
  font-size: var(--fs-small);
  color: var(--ink-soft);
  line-height: 1.7;
}

.skill-list {
  display: grid;
  gap: 28px clamp(24px, 3.5vw, 56px);
  grid-template-columns: minmax(0, 1fr);
}

.skill h4 {
  margin: 0;
  font-family: var(--serif);
  font-size: var(--fs-body);
  font-weight: 700;
  line-height: 1.5;
}

.skill h4 a {
  text-decoration: none;
}

.skill h4 a:hover {
  color: var(--accent);
}

.skill .sid {
  display: block;
  font-family: var(--sans);
  font-weight: 400;
  font-size: var(--fs-small);
  color: var(--ink-soft);
  letter-spacing: 0.02em;
  overflow-wrap: anywhere;
}

.skill p {
  margin-top: 6px;
  font-size: var(--fs-small);
  line-height: 1.8;
  color: var(--ink-soft);
}

@media (min-width: 720px) {
  .skill-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 960px) {
  .skill-group {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
  }

  .group-head {
    grid-column: 1 / span 3;
    position: sticky;
    top: calc(var(--header-h) + 24px);
    align-self: start;
  }

  .skill-list {
    grid-column: 4 / span 9;
  }
}

/* 满宽色面里的分组需要把内容拉回版心 */
.skills-bleed {
  margin-top: clamp(32px, 4vw, 56px);
}

/* ---------- 直接这样说 ---------- */

.say-list {
  display: grid;
  gap: 0;
  margin-top: clamp(32px, 4vw, 56px);
}

.say {
  display: grid;
  gap: 8px;
  padding-block: clamp(20px, 2.6vw, 32px);
  position: relative;
  isolation: isolate;
}

.say::before {
  content: "";
  position: absolute;
  inset: 0 calc(var(--margin) * -0.5);
  z-index: -1;
  background: var(--surface-2);
  transform: scaleY(0);
  transform-origin: 50% 100%;
  transition: transform 0.35s var(--ease);
}

.say .ask {
  font-family: var(--serif);
  font-weight: 600;
  font-size: var(--fs-lead);
  line-height: 1.6;
  text-wrap: pretty;
}

.say .by {
  font-size: var(--fs-small);
  color: var(--ink-soft);
}

.say .by b {
  color: var(--accent);
  font-weight: 700;
}

.routes {
  margin-top: clamp(36px, 5vw, 64px);
}

.routes h3 {
  font-size: var(--fs-lead);
  margin-bottom: 14px;
}

.routes ol {
  display: grid;
  gap: 12px;
}

.routes li {
  padding: 4px 0 0;
}

.routes li b {
  font-family: var(--serif);
  display: block;
  margin-bottom: 2px;
}

@media (min-width: 960px) {
  .say {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    column-gap: 48px;
    align-items: baseline;
  }

  .say .by {
    text-align: right;
  }

  .routes ol {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 安装 ---------- */

.install-grid {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
  grid-template-columns: minmax(0, 1fr);
  margin-top: clamp(32px, 4vw, 56px);
}

.tablist {
  display: none;
}

.js .tablist {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tab {
  min-height: 48px;
  padding: 8px 18px;
  border: 0;
  border-radius: var(--radius);
  background: var(--surface-2);
  color: var(--ink);
  font: inherit;
  font-size: var(--fs-small);
  font-weight: 500;
  cursor: pointer;
  text-align: left;
  transition: background-color 0.2s var(--ease), color 0.2s var(--ease), transform 0.2s var(--ease);
}

.tab:hover {
  transform: translateY(-1px);
  background: color-mix(in srgb, var(--surface-2) 82%, var(--ink));
}

.tab[aria-selected="true"] {
  background: var(--accent);
  color: var(--on-accent);
}

.panel + .panel {
  margin-top: clamp(32px, 4vw, 48px);
}

.js .panel + .panel {
  margin-top: 0;
}

.js .panel[hidden] {
  display: none;
}

.js .panel .panel-title {
  display: none;
}

.panel-title {
  font-size: var(--fs-lead);
  margin-bottom: 12px;
}

.panel p {
  margin-top: 12px;
  max-width: 44em;
}

.panel p.small {
  color: var(--ink-soft);
}

.panel.is-entering {
  animation: panel-in 0.4s var(--ease);
}

@keyframes panel-in {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

.codebox {
  position: relative;
  margin-top: 16px;
  background: var(--code-bg);
  color: var(--code-ink);
  border-radius: var(--radius);
}

.codebox pre {
  margin: 0;
  padding: 20px 96px 20px 20px;
  overflow-x: auto;
  font-family: ui-monospace, "Cascadia Mono", "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 0.9375rem;
  line-height: 1.75;
  letter-spacing: 0;
  tab-size: 2;
}

.codebox code {
  font-family: inherit;
}

.codebox .label {
  display: block;
  padding: 10px 20px 0;
  font-size: 0.8125rem;
  line-height: 1.5;
  color: var(--code-soft);
}

.codebox .label + pre {
  padding-top: 6px;
}

.copy {
  position: absolute;
  top: 10px;
  right: 10px;
  min-width: 68px;
  min-height: 36px;
  padding: 4px 12px;
  border: 0;
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.12);
  color: var(--code-ink);
  font: inherit;
  font-size: 0.875rem;
  cursor: pointer;
  transition: background-color 0.2s var(--ease), transform 0.2s var(--ease);
}

.copy:hover {
  background: rgba(255, 255, 255, 0.22);
}

.copy:active {
  transform: scale(0.95);
}

.copy.is-done {
  background: var(--accent);
  color: var(--on-accent);
}

@media (max-width: 719px) {
  .codebox pre {
    padding-right: 20px;
  }

  .copy {
    position: static;
    display: block;
    margin: 0 10px 10px auto;
  }
}

.install-side h3 {
  font-size: var(--fs-lead);
  margin-bottom: 8px;
}

.install-side p {
  color: var(--ink-soft);
}

.install-side p + h3,
.install-side .codebox + h3 {
  margin-top: 32px;
}

@media (min-width: 960px) {
  .install-grid {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    column-gap: 64px;
  }
}

/* ---------- 边界与许可 ---------- */

.limit-list {
  display: grid;
  gap: 18px;
}

.limit-list li {
  padding-left: 1.2em;
  position: relative;
}

.limit-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.8em;
  width: 0.5em;
  height: 0.5em;
  background: var(--accent);
}

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

.notice {
  background: var(--surface-2);
  padding: clamp(20px, 3vw, 32px);
  margin-top: clamp(24px, 3vw, 36px);
}

.notice strong {
  font-family: var(--serif);
  color: var(--accent);
}

.license-card {
  background: var(--field-red);
  color: var(--field-red-ink);
  padding: clamp(24px, 4vw, 48px);
}

.license-card h3 {
  font-size: calc(var(--fs-head) * 0.72);
  line-height: 1.25;
  font-weight: 800;
}

.license-card p {
  margin-top: 16px;
  color: var(--field-red-soft);
}

.license-card p strong {
  color: var(--field-red-ink);
}

.license-card a {
  color: var(--field-red-ink);
}

.license-card a:hover {
  color: var(--field-red-ink);
}

@media (min-width: 960px) {
  .limits {
    grid-column: 1 / span 6;
  }

  .license-card {
    grid-column: 7 / span 6;
  }
}

/* ---------- 常见问题 ---------- */

.faq-list {
  margin-top: clamp(32px, 4vw, 56px);
  display: grid;
  gap: clamp(36px, 5vw, 64px);
}

.faq-item {
  display: grid;
  gap: 12px;
}

.faq-item h3 {
  font-size: var(--fs-lead);
  line-height: 1.4;
}

.faq-item p {
  color: var(--ink-soft);
  max-width: 40em;
}

@media (min-width: 960px) {
  .faq-item {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
    column-gap: 64px;
    align-items: baseline;
  }
}

/* ---------- 页脚 ---------- */

.site-footer {
  background: var(--field-red);
  color: var(--field-red-ink);
  padding-top: clamp(48px, 6vw, 88px);
  overflow: hidden;
}

.site-footer a {
  color: var(--field-red-ink);
  text-decoration-color: var(--field-red-line);
}

.site-footer a:hover {
  color: var(--field-red-ink);
  text-decoration-color: currentColor;
}

.foot-cols {
  display: grid;
  gap: 32px 24px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.foot-cols h2 {
  font-family: var(--serif);
  font-size: var(--fs-body);
  font-weight: 700;
  margin-bottom: 10px;
}

.foot-cols li + li {
  margin-top: 4px;
}

.foot-cols .small,
.foot-cols li {
  font-size: var(--fs-small);
  color: var(--field-red-soft);
}

.foot-cols li a {
  color: var(--field-red-ink);
}

.foot-note {
  margin-top: clamp(40px, 5vw, 64px);
  max-width: 54em;
  font-size: var(--fs-small);
  line-height: 1.8;
  color: var(--field-red-soft);
}

.wordmark {
  margin-top: clamp(40px, 8vw, 120px);
  margin-bottom: clamp(16px, 2vw, 28px);
  display: block;
  width: 100%;
  height: auto;
  transform-origin: 0 100%;
}

.wordmark text {
  fill: var(--field-red-ink);
  font-family: var(--serif);
  font-weight: 800;
}

@media (min-width: 760px) {
  .foot-cols {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@supports (animation-timeline: view()) {
  @media (prefers-reduced-motion: no-preference) {
    .wordmark {
      animation: wordmark-grow linear both;
      animation-timeline: view();
      animation-range: entry 0% cover 55%;
    }

    .sheet-wrap {
      animation: sheet-drift linear both;
      animation-timeline: view();
      animation-range: exit 0% exit 100%;
    }
  }
}

@keyframes wordmark-grow {
  from {
    transform: scale(0.94);
  }
  to {
    transform: scale(1);
  }
}

@keyframes sheet-drift {
  from {
    transform: translateY(0);
  }
  to {
    transform: translateY(-36px);
  }
}

/* ---------- 进场与悬停 ---------- */

.js [data-reveal] {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.7s var(--ease) var(--d, 0ms), transform 0.7s var(--ease) var(--d, 0ms);
}

.js [data-reveal].in,
.js.reveal-all [data-reveal] {
  opacity: 1;
  transform: none;
}

.skill,
.rule,
.faq-item,
.delta > div {
  transition: transform 0.3s var(--ease);
}

@media (hover: hover) {
  .skill:hover,
  .rule:hover {
    transform: translateX(4px);
  }

  .say:hover::before {
    transform: scaleY(1);
  }
}

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

  .js [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .sheet {
    transform: none;
  }
}

@media print {
  .site-header,
  .copy,
  .tablist {
    display: none;
  }

  .js [data-reveal] {
    opacity: 1;
    transform: none;
  }
}