/*
 * [INPUT]: index.html 与 compare.html 的共享语义类名和浏览器媒体查询。
 * [OUTPUT]: 统一设计变量、页面布局、组件状态及固定尺寸的 SVG 操作箭头。
 * [POS]: dist 的视觉层，供页面与演示模块共享，避免动画逻辑决定布局。
 * [PROTOCOL]: 变更时更新此头部，然后检查 CLAUDE.md
 */

:root {
  color-scheme: dark;
  --bg: #080b0a;
  --panel: #101410;
  --ink: #f0f2eb;
  --subtle: #8a938a;
  --accent: #c1ff72;
  --line: #283026;
  --font: "DM Sans", "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono: "SFMono-Regular", Consolas, monospace;
  --display: "Space Grotesk", var(--font);
}
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: 100px;
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.7 var(--font);
  -webkit-font-smoothing: antialiased;
}
a {
  color: inherit;
  text-decoration: none;
}
button {
  font: inherit;
}
a,
button {
  -webkit-tap-highlight-color: transparent;
}
::selection {
  color: var(--bg);
  background: var(--accent);
}
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 6px;
}
.skip-link {
  position: fixed;
  z-index: 100;
  top: -80px;
  left: 20px;
  padding: 12px;
  background: var(--accent);
  color: var(--bg);
}
.skip-link:focus {
  top: 12px;
}
.site-header {
  height: 94px;
  max-width: 1440px;
  margin: auto;
  padding: 0 5.55%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
}
.brand {
  display: flex;
  align-items: center;
  font: 700 39px/1 var(--display);
  letter-spacing: -3px;
}
.brand-mark {
  font: 48px/1 Georgia;
  margin-right: 10px;
  color: var(--accent);
  transform: rotate(8deg);
}
.brand-dot {
  color: var(--accent);
}
.site-header nav {
  display: flex;
  gap: 38px;
  font-size: 14px;
  color: #bdc4b9;
}
.site-header nav a:hover {
  color: var(--accent);
}
.site-header nav a[aria-current="page"] {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 8px;
}
.header-cta {
  font-size: 14px;
  border: 1px solid #45523d;
  padding: 10px 20px;
  border-radius: 6px;
  display: flex;
  gap: 12px;
  align-items: center;
}
.header-cta:hover {
  border-color: var(--accent);
  color: var(--accent);
}
.hero {
  max-width: 1440px;
  position: relative;
  padding: 98px 5.55% 0;
  margin: auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 26px;
}
.eyebrow {
  font: 500 12px/1.6 var(--mono);
  letter-spacing: 1.7px;
  color: #a1b198;
  margin: 0 0 30px;
}
.hero .eyebrow {
  display: flex;
  align-items: center;
  gap: 10px;
}
.eyebrow > span:empty {
  height: 6px;
  width: 6px;
  display: inline-block;
  border-radius: 50%;
  background: var(--accent);
}
h1 {
  font-size: clamp(60px, 6.3vw, 94px);
  line-height: 1.16;
  letter-spacing: -5px;
  font-weight: 600;
  margin: 0;
}
.accent {
  color: var(--accent);
}
.hero-en {
  font: 400 clamp(19px, 2vw, 28px) / 1.2 var(--display);
  color: #8d9788;
  letter-spacing: -0.5px;
  margin: 25px 0 29px;
}
.hero-description {
  font-size: 17px;
  color: #a8b1a3;
  line-height: 1.85;
}
.hero-actions {
  display: flex;
  align-items: center;
  gap: 26px;
  margin-top: 33px;
}
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  border: 0;
  padding: 15px 22px;
  border-radius: 5px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition:
    transform 0.2s,
    background 0.2s;
}
/* ---- 操作箭头不依赖字体；长文案换行时保持尺寸与居中 ---- */
.icon-arrow {
  display: inline-block;
  width: 16px;
  height: 16px;
  flex: none;
  align-self: center;
  vertical-align: middle;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.button > span,
.header-cta > span {
  min-width: 0;
}
.primary {
  background: var(--accent);
  color: #11170c;
}
.primary:hover {
  background: #d4ff9e;
  transform: translateY(-2px);
}
.text-link {
  font-size: 14px;
  color: #c1c8bc;
  display: flex;
  align-items: center;
  gap: 14px;
}
.text-link:hover {
  color: var(--accent);
}
.hero-tags {
  display: flex;
  gap: 22px;
  font-size: 12px;
  color: #85917d;
  margin-top: 34px;
}
.hero-tags span:before {
  content: "✓";
  color: #a1ba8b;
  margin-right: 8px;
}
.hero-visual {
  position: relative;
  min-height: 495px;
  border: 1px solid #2b3625;
  border-radius: 10px;
  background:
    radial-gradient(ellipse at 55% 49%, #34492345, transparent 65%),
    linear-gradient(#ffffff02, #ffffff00);
  overflow: hidden;
}
.visual-top,
.visual-bottom {
  position: absolute;
  left: 25px;
  right: 25px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font: 11px var(--mono);
  color: #849077;
  letter-spacing: 1px;
}
.visual-top {
  top: 24px;
}
.visual-bottom {
  bottom: 25px;
  font-size: 12px;
}
.visual-line {
  height: 1px;
  width: 35%;
  background: #33442a;
}

.engine-word {
  font: 600 110px/1 var(--display);
  letter-spacing: -10px;
}
.engine-word span {
  color: var(--accent);
}

.hero-footer {
  grid-column: 1/-1;
  border-bottom: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 44px;
  padding: 25px 0;
  color: #7b8574;
  font: 10px var(--mono);
  letter-spacing: 1px;
}
.hero-footer a {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font: 12px var(--font);
  letter-spacing: 0;
}
.section-shell {
  max-width: 1280px;
  margin: 0 auto;
  padding: 108px 0;
}
h2 {
  font-weight: 500;
  font-size: 48px;
  line-height: 1.3;
  letter-spacing: -2px;
  margin: 0;
}
.muted {
  color: #747f6d;
}
.section-description {
  color: #9ba692;
  max-width: 510px;
  line-height: 1.9;
}
@media (min-width: 1441px) {
  .hero {
    padding-top: 114px;
  }
}
@media (max-width: 1350px) {
  .section-shell {
    margin: 0 5.55%;
  }
  .hero {
    padding-top: 75px;
  }
  .hero-visual {
    min-height: 470px;
  }
  .hero-actions {
    gap: 18px;
  }
  .button {
    gap: 18px;
    padding: 14px 18px;
  }
}
@media (max-width: 900px) {
  .site-header {
    height: 78px;
  }
  .site-header nav {
    gap: 20px;
  }
  .hero {
    gap: 18px;
    padding-top: 60px;
  }
  h1 {
    font-size: 65px;
  }
  .hero-actions {
    flex-wrap: wrap;
    gap: 18px;
  }
  .hero-visual {
    min-height: 460px;
  }
  .eyebrow {
    font-size: 10px;
    letter-spacing: 1px;
  }
  .hero-footer {
    margin-top: 25px;
  }
  .section-shell {
    padding: 75px 0;
  }
}
@media (max-width: 650px) {
  .site-header {
    padding: 0 6%;
    height: 76px;
  }
  .site-header nav {
    display: none;
  }
  .brand {
    font-size: 32px;
  }
  .brand-mark {
    font-size: 40px;
  }
  .header-cta {
    padding: 8px 14px;
    gap: 10px;
  }
  .hero {
    grid-template-columns: 1fr;
    padding: 50px 6% 0;
    gap: 35px;
  }
  h1 {
    font-size: clamp(3.3rem, 16.5vw, 4.25rem);
    letter-spacing: -4px;
  }
  .hero .eyebrow {
    font-size: 10px;
    margin-bottom: 27px;
  }
  .hero-en {
    font-size: 23px;
  }
  .hero-description {
    font-size: 16px;
  }
  .hero-actions {
    gap: 23px;
    flex-wrap: nowrap;
  }
  .button {
    padding: 14px 17px;
    gap: 12px;
  }
  .text-link {
    font-size: 13px;
    gap: 8px;
  }
  .hero-tags {
    margin-top: 25px;
  }
  .hero-visual {
    min-height: 390px;
  }
  .hero-footer {
    margin-top: 0;
    padding: 18px 0;
    font-size: 8px;
    letter-spacing: 0.5px;
  }
  .hero-footer > span {
    max-width: 220px;
  }
  .section-shell {
    margin: 0 6%;
    padding: 70px 0;
  }
  h2 {
    font-size: 36px;
    letter-spacing: -1.5px;
  }
  .eyebrow {
    font-size: 10px;
  }
  .section-description {
    font-size: 16px;
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }
}