/* 夜色AI官网的基础排版与配色 */
:root {
  --night: #141421;
  --panel: #1c1b2c;
  --ink: #f4f1f8;
  --muted: #b4b0c2;
  --violet: #a995ec;
  --line: #ffffff26;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--night); color: var(--ink); font-family: "PingFang SC", "Microsoft YaHei", system-ui, sans-serif; }
a { color: inherit; text-decoration: none; }
a:focus-visible { outline: 2px solid var(--violet); outline-offset: 4px; }
img { max-width: 100%; }
.section-wrap, .site-header, .site-footer { width: min(1160px, calc(100% - 48px)); margin-right: auto; margin-left: auto; }

/* 顶栏只保留导航和一个明确的下载操作。 */
.site-header { display: flex; align-items: center; justify-content: space-between; gap: 24px; height: 82px; }
.brand { display: inline-flex; align-items: center; gap: 10px; white-space: nowrap; font-size: 20px; font-weight: 750; letter-spacing: -.05em; }
.brand-symbol { display: grid; width: 34px; height: 34px; border: 1px solid #c2b2ef66; border-radius: 9px; background: #302947; color: #ded3ff; font-size: 17px; letter-spacing: 0; place-items: center; }
.brand-accent { margin-left: 2px; color: #c4b2f3; }
.site-header nav { display: flex; align-items: center; gap: 32px; color: #cac6d3; font-size: 13px; }
.site-header nav a:hover, .site-footer > a:last-child:hover { color: #fff; }
.header-download { padding: 11px 19px; border: 1px solid #a794d7; border-radius: 8px; color: #eee5ff; font-size: 13px; font-weight: 700; white-space: nowrap; }
.header-download:hover { background: #2a253c; }

/* 首屏使用截图和文字形成主体，不在截图周围堆放装饰标签。 */
.hero { overflow: hidden; border-top: 1px solid #ffffff0d; background: linear-gradient(110deg, #171724 12%, #252037 76%, #302642); }
.hero-inner { display: grid; grid-template-columns: 1.05fr .95fr; align-items: center; gap: 55px; width: min(1160px, calc(100% - 48px)); min-height: 620px; margin: auto; }
.eyebrow { margin: 0 0 22px; color: #baa9e6; font-size: 12px; font-weight: 700; letter-spacing: .08em; }
.hero h1, .section-intro h2, .showcase h2, .guide h2, .download-banner h2 { margin: 0; font-weight: 750; letter-spacing: -.065em; line-height: 1.22; }
.hero h1 { font-size: clamp(43px, 4.7vw, 60px); }
.hero h1 em { color: #c8b7f6; font-style: normal; }
.hero-lead { max-width: 470px; margin: 26px 0 30px; color: #d2cedc; font-size: 16px; line-height: 1.9; }
.hero-actions { display: flex; align-items: center; gap: 26px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 51px; padding: 0 24px; border: 1px solid transparent; border-radius: 9px; font-size: 14px; font-weight: 750; white-space: nowrap; transition: background .2s, transform .2s; }
.button:hover { transform: translateY(-2px); }
.button-primary { background: #b9a6ef; color: #201c2d; }
.button-primary:hover { background: #d0c1f9; }
.hero-secondary { padding-bottom: 5px; border-bottom: 1px solid #9d90af; color: #ded8e9; font-size: 14px; }
.hero-secondary:hover { color: #fff; border-color: #fff; }
.hero-note { margin: 16px 0 0; color: #a9a4b7; font-size: 12px; }
.hero-art { position: relative; display: grid; min-height: 590px; place-items: center; }
.hero-art:before { position: absolute; top: 54px; right: 12px; bottom: 58px; left: 74px; border: 1px solid #c3b1e633; border-radius: 24px; background: linear-gradient(160deg, #8267aa26, #ffffff05); content: ""; }
.preview-phone { position: relative; width: 242px; height: 520px; overflow: hidden; border: 6px solid #2a273a; border-radius: 32px; background: #211e31; box-shadow: 0 24px 55px #0c0a1775; }
.preview-phone img { display: block; width: 100%; height: 100%; object-fit: cover; object-position: top; }
.preview-caption { position: absolute; right: 18px; bottom: 44px; display: grid; gap: 5px; margin: 0; padding: 13px 17px; border: 1px solid #ffffff29; border-radius: 9px; background: #1e1b2fe8; color: #f2edf8; font-size: 12px; font-weight: 700; }
.preview-caption span { color: #bbb4ca; font-size: 10px; font-weight: 400; }

/* 功能卡片为说明内容，不使用会被误认成按钮的箭头。 */
.features { padding: 100px 0 110px; }
.section-intro h2, .showcase h2, .guide h2 { font-size: clamp(34px, 3.6vw, 48px); }
.section-intro > p:last-child { margin: 16px 0 35px; color: var(--muted); font-size: 15px; }
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.feature-card { min-height: 250px; padding: 28px; border: 1px solid var(--line); border-radius: 13px; background: var(--panel); }
.feature-label { display: inline-block; padding-bottom: 9px; border-bottom: 1px solid #8e7eb0; color: #bdaaeb; font-size: 12px; font-weight: 700; }
.feature-card h3 { margin: 38px 0 12px; font-size: 22px; letter-spacing: -.04em; }
.feature-card p { max-width: 295px; margin: 0; color: #bdb8ca; font-size: 14px; line-height: 1.85; }

/* 界面区使用另一张实际截图，避免同一画面重复出现。 */
.showcase { background: #e9e6ef; color: #252132; }
.showcase-inner { display: grid; grid-template-columns: 1fr 1fr; align-items: center; gap: 60px; width: min(1160px, calc(100% - 48px)); min-height: 650px; margin: auto; }
.showcase .eyebrow { color: #766598; }
.showcase h2 { line-height: 1.3; }
.showcase-copy > p:not(.eyebrow) { max-width: 440px; margin: 24px 0; color: #655e70; font-size: 15px; line-height: 1.85; }
.inline-link { display: inline-block; padding: 0 0 6px; border-bottom: 1px solid #6a568f; color: #594479; font-size: 14px; font-weight: 750; }
.inline-link:hover { color: #2d2141; border-color: #2d2141; }
.showcase-screen { width: 260px; height: 530px; margin: 48px auto 42px; }
.showcase-screen img { display: block; width: 100%; height: 100%; object-fit: cover; object-position: top; border: 6px solid #fff; border-radius: 30px; box-shadow: 0 22px 55px #30263e38; }
.showcase-screen figcaption { margin-top: 13px; color: #746e7d; font-size: 11px; text-align: center; }

/* 使用说明把安装步骤和文明使用提醒放在一起。 */
.guide { padding: 100px 0 90px; }
.guide-heading { margin-bottom: 38px; }
.guide-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; border-top: 1px solid var(--line); }
.guide-list > div { padding-top: 24px; }
.guide-list span { color: #b7a6e6; font-size: 12px; }
.guide-list h3 { margin: 24px 0 10px; font-size: 19px; }
.guide-list p { max-width: 300px; margin: 0; color: var(--muted); font-size: 14px; line-height: 1.8; }
.guide-disclaimer { margin: 42px 0 0; padding: 15px 19px; border-left: 2px solid #aa95e3; background: #211e2f; color: #c3bdcf; font-size: 12px; line-height: 1.8; }
.download-banner { display: flex; align-items: center; justify-content: space-between; gap: 30px; min-height: 220px; padding: 40px 48px; margin-bottom: 85px; border: 1px solid #8b7baf; border-radius: 15px; background: #2c263c; }
.download-banner .eyebrow { margin-bottom: 12px; }
.download-banner h2 { font-size: clamp(32px, 3.5vw, 46px); }
.download-banner p:last-child { margin: 15px 0 0; color: #cbc3d9; font-size: 14px; }
.button-light { background: #eee7fc; color: #2b213d; }
.button-light:hover { background: #fff; }
.site-footer { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding-bottom: 35px; color: #a9a3b6; }
.site-footer .brand { color: #f2edf7; font-size: 17px; }
.site-footer .brand-symbol { width: 28px; height: 28px; font-size: 14px; }
.site-footer p, .site-footer > a:last-child { font-size: 12px; }

/* 手机端优先保证文字、截图和下载入口可读。 */
@media (max-width: 760px) {
  .section-wrap, .site-header, .site-footer, .hero-inner, .showcase-inner { width: calc(100% - 32px); }
  .site-header { height: 68px; gap: 10px; }
  .site-header nav { display: none; }
  .brand { font-size: 18px; }
  .header-download { padding: 9px 11px; font-size: 11px; }
  .hero-inner { grid-template-columns: 1fr; gap: 5px; padding-top: 60px; }
  .hero h1 { font-size: clamp(31px, 8.9vw, 54px); }
  .hero-lead { margin: 20px 0 26px; font-size: 14px; }
  .hero-actions { flex-wrap: wrap; gap: 21px; }
  .button { min-height: 48px; padding: 0 17px; font-size: 13px; }
  .hero-secondary { font-size: 12px; }
  .hero-art { min-height: 465px; margin: 0 -16px; }
  .hero-art:before { top: 45px; right: 28px; bottom: 28px; left: 28px; }
  .preview-phone { width: 186px; height: 405px; border-width: 5px; border-radius: 26px; }
  .preview-caption { right: 10px; bottom: 30px; }
  .features { padding: 75px 0 80px; }
  .section-intro h2, .showcase h2, .guide h2 { font-size: 34px; }
  .feature-grid { grid-template-columns: 1fr; gap: 12px; }
  .feature-card { min-height: 185px; padding: 22px; }
  .feature-card h3 { margin: 23px 0 8px; font-size: 20px; }
  .showcase-inner { grid-template-columns: 1fr; gap: 15px; padding: 66px 0 60px; }
  .showcase-screen { width: 205px; height: 420px; margin: 20px auto 35px; }
  .guide { padding: 75px 0; }
  .guide-list { grid-template-columns: 1fr; gap: 0; }
  .guide-list > div { padding: 20px 0; border-bottom: 1px solid var(--line); }
  .guide-list h3 { margin: 12px 0 8px; }
  .guide-disclaimer { margin-top: 25px; }
  .download-banner { display: block; min-height: auto; padding: 31px 26px; margin-bottom: 65px; }
  .download-banner .button { margin-top: 23px; }
  .site-footer { display: block; padding-bottom: 30px; }
  .site-footer p { margin: 17px 0; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .button { transition: none; }
}