/* AI 翻译助手 · 宣传站点
   方向：夜间阅读。深靛灰底，浅靛蓝是"译文"的颜色，琥珀只做极少量点缀。 */

:root {
  color-scheme: dark;
  --bg: #0E1016;
  --bg-alt: #141722;
  --surface: #1A1E2B;
  --line: #272C3C;
  --line-strong: #394058;
  --text: #ECEDF3;
  --muted: #A4A9BA;
  --brand: #4856E0;
  --brand-hover: #5A68EE;
  --brand-fg: #A9B3FF;
  --on-brand: #FFFFFF;
  --ink: #BCC4FF;
  --accent: #FFC857;
  --ok: #4FD08F;
  --seg-on: #2C3350;
  --code-bg: #07080C;
  --radius: 14px;
  --radius-sm: 9px;
  --shadow: 0 1px 2px rgba(0, 0, 0, .4), 0 20px 48px -16px rgba(0, 0, 0, .7);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --serif: Charter, "Iowan Old Style", Georgia, "Times New Roman", serif;
  --mono: ui-monospace, "Cascadia Code", "SF Mono", Consolas, monospace;
  --ease: cubic-bezier(.2, .7, .2, 1);
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.7 var(--font);
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; }
a { color: inherit; }
h1, h2, h3, p, ul, ol, figure { margin: 0; }
ul, ol { padding: 0; list-style: none; }
code, kbd { font-family: var(--mono); }
p code {
  font-size: .88em;
  padding: .1em .4em;
  border-radius: 5px;
  background: var(--bg-alt);
  overflow-wrap: anywhere;
}
kbd {
  display: inline-block;
  min-width: 1.9em;
  padding: .12em .45em;
  font-size: .78em;
  line-height: 1.5;
  text-align: center;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--line-strong);
  border-bottom-width: 2px;
  border-radius: 6px;
}

:focus-visible { outline: 2px solid var(--brand-fg); outline-offset: 3px; border-radius: 6px; }

.sr-only {
  position: absolute; width: 1px; height: 1px; overflow: hidden;
  clip: rect(0 0 0 0); white-space: nowrap;
}
.skip-link {
  position: absolute; left: 12px; top: -48px; z-index: 100;
  padding: 8px 14px; border-radius: 8px;
  background: var(--brand); color: var(--on-brand); text-decoration: none;
  transition: top .2s var(--ease);
}
.skip-link:focus { top: 12px; }

.icon-sprite { position: absolute; width: 0; height: 0; overflow: hidden; }
.icon {
  width: 20px; height: 20px; flex: none;
  fill: none; stroke: currentColor; stroke-width: 1.75;
  stroke-linecap: round; stroke-linejoin: round;
}

.wrap { width: 100%; max-width: 1120px; margin: 0 auto; padding: 0 24px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 46px; padding: 0 20px;
  font: 600 15px/1 var(--font);
  text-decoration: none; white-space: nowrap;
  border-radius: 999px; border: 1px solid transparent;
  cursor: pointer;
  transition: background-color .18s var(--ease), border-color .18s var(--ease), color .18s var(--ease);
}
.btn--sm { min-height: 38px; padding: 0 16px; font-size: 14px; }
.btn--primary { background: var(--brand); color: var(--on-brand); }
.btn--primary:hover { background: var(--brand-hover); }
.btn--ghost { color: var(--text); border-color: var(--line-strong); background: transparent; }
.btn--ghost:hover { background: var(--surface); border-color: var(--muted); }

/* ---------- 顶栏 ---------- */
.topbar {
  position: sticky; top: 0; z-index: 50;
  background: rgba(14, 16, 22, .82);
  -webkit-backdrop-filter: saturate(1.4) blur(12px);
  backdrop-filter: saturate(1.4) blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color .2s var(--ease);
}
.topbar.is-stuck { border-bottom-color: var(--line); }
.topbar__inner { display: flex; align-items: center; gap: 24px; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; margin-right: auto; }
.brand__mark { width: 32px; height: 32px; border-radius: 8px; }
.brand__name { font-weight: 700; font-size: 16px; letter-spacing: .01em; }
.nav { display: flex; align-items: center; gap: 4px; }
.nav a {
  padding: 8px 12px; border-radius: 8px;
  font-size: 15px; color: var(--muted); text-decoration: none;
  transition: color .15s, background-color .15s;
}
.nav a:hover { color: var(--text); background: var(--bg-alt); }
.nav-toggle { display: none; }

/* ---------- 首屏 ---------- */
.hero { padding: 72px 0 40px; }
.hero__inner {
  display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.08fr);
  gap: 56px; align-items: center;
}
.eyebrow {
  font-size: 13px; font-weight: 600; letter-spacing: .08em;
  color: var(--brand-fg); margin-bottom: 14px;
}
.hero__title {
  font-size: clamp(36px, 5.2vw, 58px); line-height: 1.16;
  font-weight: 800; letter-spacing: -.01em;
}
.hero__lead { margin-top: 22px; font-size: 18px; color: var(--muted); max-width: 30em; }
.hero__cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.hero__meta { display: flex; flex-wrap: wrap; gap: 6px 20px; margin-top: 22px; font-size: 14px; color: var(--muted); }
.hero__meta li { display: flex; align-items: center; gap: 8px; }
.hero__meta li::before { content: ""; width: 6px; height: 6px; border-radius: 50%; background: var(--ok); }

/* 阅读器演示 */
.reader {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}
.reader__bar {
  display: flex; align-items: center; gap: 14px;
  padding: 11px 16px; background: var(--bg-alt); border-bottom: 1px solid var(--line);
}
.reader__dots { display: flex; gap: 6px; }
.reader__dots i { width: 10px; height: 10px; border-radius: 50%; background: var(--line-strong); }
.reader__url {
  flex: 1; min-width: 0; padding: 4px 12px; border-radius: 999px;
  background: var(--surface); font: 12.5px/1.5 var(--mono); color: var(--muted);
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.reader__tools {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 10px;
  padding: 14px 20px 0;
}
.reader__lang { font-size: 13px; color: var(--muted); }
.seg { display: inline-flex; padding: 3px; gap: 2px; border-radius: 999px; background: var(--bg-alt); }
.seg button {
  min-height: 34px; padding: 0 14px;
  font: 500 13.5px/1 var(--font); color: var(--muted);
  background: transparent; border: 0; border-radius: 999px; cursor: pointer;
  transition: background-color .18s var(--ease), color .18s var(--ease);
}
.seg button:hover { color: var(--text); }
.seg button[aria-pressed="true"] { background: var(--seg-on); color: var(--text); box-shadow: 0 1px 3px rgba(0, 0, 0, .4); }

.reader__body { padding: 18px 24px 26px; display: grid; gap: 16px; }
.pair { display: grid; gap: 6px; }
.pair .s { font-family: var(--serif); font-size: 16.5px; line-height: 1.6; color: var(--text); }
.pair .t {
  font-size: 15.5px; line-height: 1.7; color: var(--ink);
  padding-left: 12px; border-left: 3px solid #6B7AFF;
}
.pair--title .s { font-size: 23px; font-weight: 700; line-height: 1.3; }
.pair--title .t { font-size: 19px; font-weight: 700; line-height: 1.45; }
.reader[data-view="source"] .t,
.reader[data-view="target"] .s { display: none; }
.reader[data-view="target"] .t { padding-left: 0; border-left: 0; color: var(--text); }

/* ---------- 通用区块 ---------- */
.section { padding: 96px 0; }
.section--alt { background: var(--bg-alt); }
.sec-head { max-width: 640px; margin-bottom: 48px; }
.h2 { font-size: clamp(28px, 3.6vw, 38px); line-height: 1.25; font-weight: 800; letter-spacing: -.005em; }
.sec-head__lead, .lead { margin-top: 14px; font-size: 17px; color: var(--muted); }

/* 三种用法 */
.uses { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.use {
  display: flex; flex-direction: column;
  padding: 22px; background: var(--surface);
  border: 1px solid var(--line); border-radius: var(--radius);
}
.use__art {
  height: 148px; padding: 16px; margin-bottom: 22px;
  border-radius: var(--radius-sm); background: var(--bg);
  font-size: 13px; line-height: 1.55; overflow: hidden;
}
.mini-s { font-family: var(--serif); color: var(--text); }
.mini-t { color: var(--ink); padding-left: 9px; border-left: 2px solid #6B7AFF; margin: 2px 0 10px; }
.use__art--sel { position: relative; }
.mini-doc { font-family: var(--serif); font-size: 14px; }
.mini-doc mark { background: rgba(107, 122, 255, .3); color: inherit; padding: 1px 2px; border-radius: 3px; }
.mini-pop {
  position: absolute; left: 16px; right: 16px; bottom: 16px;
  padding: 10px 12px; border-radius: 10px;
  background: var(--surface); color: var(--ink); font-weight: 600;
  box-shadow: 0 8px 20px -6px rgba(0, 0, 0, .6); border: 1px solid var(--line);
}
.use__art--sum { border-left: 3px solid var(--accent); }
.mini-lead { font-weight: 600; margin-bottom: 8px; }
.mini-list { display: grid; gap: 4px; color: var(--muted); }
.mini-list li::before { content: "· "; color: var(--text); font-weight: 700; }
.use__t { font-size: 19px; font-weight: 700; }
.use__d { margin-top: 8px; font-size: 15px; color: var(--muted); flex: 1; }
.keys { display: flex; gap: 5px; margin-top: 18px; }

.details {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px 32px; margin-top: 56px; padding-top: 40px; border-top: 1px solid var(--line);
}
.details li { display: flex; gap: 14px; }
.details .icon { color: var(--brand-fg); margin-top: 3px; }
.details b { display: block; font-size: 15.5px; }
.details span { display: block; font-size: 14.5px; color: var(--muted); }

/* 模型与隐私 */
.split { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr); gap: 64px; align-items: center; }
.checks { display: grid; gap: 12px; margin-top: 28px; }
.checks li { display: flex; gap: 12px; font-size: 15.5px; }
.checks .icon { color: var(--ok); margin-top: 3px; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 28px; }
.chips li {
  padding: 5px 14px; font-size: 14px; border-radius: 999px;
  background: var(--surface); border: 1px solid var(--line);
}
.config {
  padding: 22px; background: var(--surface);
  border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow);
}
.config__head { display: flex; align-items: center; gap: 10px; font-weight: 700; margin-bottom: 16px; }
.config__head img { border-radius: 5px; }
.field { display: grid; gap: 4px; margin-top: 12px; }
.field span { font-size: 13px; color: var(--muted); }
.field b {
  font: 500 14px/1.4 var(--mono); padding: 10px 12px;
  border: 1px solid var(--line-strong); border-radius: var(--radius-sm); background: var(--bg);
  overflow-wrap: anywhere;
}
.config__foot { display: flex; align-items: center; gap: 8px; margin-top: 18px; font-size: 14px; color: var(--ok); font-weight: 600; }
.ok-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--ok); box-shadow: 0 0 0 4px rgba(79, 208, 143, .16); }

/* 安装 */
.steps { display: grid; grid-template-columns: minmax(0, 1.7fr) repeat(3, minmax(0, 1fr)); gap: 28px; counter-reset: step; }
.step { position: relative; padding-top: 56px; counter-increment: step; min-width: 0; }
.step::before {
  content: counter(step);
  position: absolute; top: 0; left: 0;
  display: grid; place-items: center; width: 36px; height: 36px;
  border-radius: 50%; background: var(--brand); color: var(--on-brand);
  font-weight: 700; font-size: 15px;
}
.step:not(:last-child)::after {
  content: ""; position: absolute; top: 18px; left: 48px; right: -8px;
  border-top: 1px dashed var(--line-strong);
}
.step__t { font-size: 17px; font-weight: 700; }
.step__d { margin-top: 8px; font-size: 15px; color: var(--muted); }
.cmd {
  display: flex; align-items: center; gap: 8px;
  margin-top: 14px; padding: 6px 6px 6px 14px;
  background: var(--code-bg); color: #ECEDF2; border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}
.cmd__text { flex: 1; min-width: 0; font-size: 13px; line-height: 1.5; overflow-wrap: anywhere; }
.cmd__copy {
  display: inline-flex; align-items: center; gap: 6px; flex: none;
  min-height: 36px; padding: 0 12px;
  font: 600 13px/1 var(--font); color: #ECEDF2;
  background: rgba(255, 255, 255, .1); border: 0; border-radius: 7px; cursor: pointer;
  transition: background-color .15s;
}
.cmd__copy .icon { width: 16px; height: 16px; }
.cmd__copy:hover { background: rgba(255, 255, 255, .18); }
.cmd__copy.is-done { background: var(--ok); color: #07140D; }
.cmd__copy:focus-visible { outline-color: var(--accent); }
.hint { margin-top: 8px; font-size: 13.5px; color: var(--muted); }
.hint.is-err { color: #FF8F7D; }

/* 常见问题 */
.faq { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.6fr); gap: 48px; align-items: start; }
.faq .sec-head { margin-bottom: 0; }
.faq__list { display: grid; gap: 10px; }
.faq details {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-sm);
}
.faq summary {
  display: flex; justify-content: space-between; align-items: center; gap: 16px;
  padding: 16px 20px; font-weight: 600; cursor: pointer; list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: ""; flex: none; width: 9px; height: 9px;
  border-right: 2px solid var(--muted); border-bottom: 2px solid var(--muted);
  transform: rotate(45deg) translateY(-3px); transition: transform .2s var(--ease);
}
.faq details[open] summary::after { transform: rotate(-135deg) translateY(-2px); }
.faq details p { padding: 0 20px 18px; font-size: 15px; color: var(--muted); }

/* 页脚 */
.footer { padding: 36px 0; border-top: 1px solid var(--line); }
.footer__inner { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 16px; }
.footer__brand { display: flex; align-items: center; gap: 10px; font-weight: 700; }
.footer__brand img { border-radius: 6px; }
.footer__ver { font: 500 12.5px/1 var(--mono); color: var(--muted); padding: 4px 8px; border-radius: 6px; background: var(--bg-alt); }
.footer__links { display: flex; flex-wrap: wrap; gap: 4px 20px; font-size: 14.5px; }
.footer__links a { color: var(--muted); text-decoration: none; }
.footer__links a:hover { color: var(--text); text-decoration: underline; }

/* ---------- 响应式 ---------- */
@media (max-width: 1000px) {
  .hero__inner, .split, .faq { grid-template-columns: minmax(0, 1fr); gap: 40px; }
  .hero { padding: 48px 0 24px; }
  .uses { grid-template-columns: minmax(0, 1fr); }
  .use { display: grid; grid-template-columns: 240px minmax(0, 1fr); column-gap: 24px; align-items: start; }
  .use__art { grid-row: span 3; margin-bottom: 0; }
  .details { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .steps { grid-template-columns: repeat(2, minmax(0, 1fr)); row-gap: 40px; }
  .step::after { display: none; }
}

@media (max-width: 800px) {
  .nav-toggle {
    display: grid; place-content: center; gap: 6px;
    width: 44px; height: 44px; margin-right: -8px;
    background: transparent; border: 0; border-radius: 10px; cursor: pointer;
  }
  .nav-toggle span { display: block; width: 20px; height: 2px; border-radius: 2px; background: var(--text); transition: transform .2s var(--ease); }
  .nav-toggle[aria-expanded="true"] span:first-child { transform: translateY(4px) rotate(45deg); }
  .nav-toggle[aria-expanded="true"] span:last-child { transform: translateY(-4px) rotate(-45deg); }
  .nav {
    display: none;
    position: absolute; top: 64px; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 2px;
    padding: 10px 16px 16px; background: var(--bg); border-bottom: 1px solid var(--line);
    box-shadow: 0 16px 24px -16px rgba(0, 0, 0, .6);
  }
  .nav.is-open { display: flex; }
  .nav a { padding: 12px; font-size: 16px; }
  .topbar__inner { gap: 12px; }
}

@media (max-width: 640px) {
  .wrap { padding: 0 18px; }
  .section { padding: 64px 0; }
  .sec-head { margin-bottom: 32px; }
  .hero__lead { font-size: 16.5px; }
  .hero__cta .btn { flex: 1 1 auto; }
  .reader__body { padding: 14px 18px 22px; }
  .pair--title .s { font-size: 20px; }
  .pair--title .t { font-size: 17px; }
  .use { display: flex; }
  .use__art { margin-bottom: 20px; }
  .details { grid-template-columns: minmax(0, 1fr); gap: 20px; }
  .steps { grid-template-columns: minmax(0, 1fr); }
  .cmd { flex-wrap: wrap; padding: 12px; }
  .cmd__copy { margin-left: auto; }
  .topbar__cta { padding: 0 14px; }
}

@media (max-width: 380px) {
  .brand__name { font-size: 15px; }
  .seg button { padding: 0 11px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; animation-duration: .01ms !important; }
}