/* ============================================================
   FrameMark 官网 · 样式
   配色取自 App 设计规范：品牌红 #F6292A / 近黑 #202224
   页面灰 #F4F6F7 / 卡片白 #FFFFFF / 描边 #E9EAEB
   ============================================================ */

:root {
  --brand-red: #F6292A;
  --brand-red-dark: #d61f20;
  --ink: #202224;
  --ink-2: #60656B;
  --ink-3: #919499;
  --bg: #F4F6F7;
  --surface: #FFFFFF;
  --border: #E9EAEB;
  --black: #000000;

  --radius-sm: 4px;
  --radius-md: 12px;
  --radius-lg: 16px;

  --shadow-soft: 0 1px 2px rgba(32, 34, 36, .04), 0 8px 24px rgba(32, 34, 36, .06);
  --shadow-card: 0 1px 3px rgba(32, 34, 36, .06);

  --maxw: 1120px;
  --pad: 20px;

  --font: "MiSans", system-ui, -apple-system, "Segoe UI", "PingFang SC",
          "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--surface);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

.container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--pad);
}

/* 跳转链接（无障碍） */
.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--brand-red);
  color: #fff;
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  z-index: 1000;
}
.skip-link:focus { left: 12px; top: 12px; }

/* ---------- 焦点样式（保留可见焦点） ---------- */
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--brand-red);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-size: 15px;
  font-weight: 500;
  padding: 11px 20px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform .12s ease, background .2s ease, box-shadow .2s ease, border-color .2s ease;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px) scale(.99); }

.btn--primary {
  background: var(--brand-red);
  color: #fff;
  box-shadow: 0 2px 8px rgba(246, 41, 42, .25);
}
.btn--primary:hover { background: var(--brand-red-dark); }

.btn--ghost {
  background: var(--surface);
  color: var(--ink);
  border-color: var(--border);
}
.btn--ghost:hover { border-color: var(--ink-3); }

.btn--lg { font-size: 16px; padding: 14px 26px; }

.btn.is-disabled,
.btn[aria-disabled="true"] {
  opacity: .5;
  cursor: not-allowed;
  pointer-events: none;
}

/* ---------- 导航 ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .82);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
}
.brand__icon { border-radius: 8px; }
.brand__name { font-size: 18px; letter-spacing: .2px; }
.brand__cn { font-size: 13px; color: var(--ink-3); }

.nav__links {
  display: flex;
  align-items: center;
  gap: 28px;
}
.nav__links a { color: var(--ink-2); font-size: 15px; transition: color .2s; }
.nav__links a:hover { color: var(--ink); }
.nav__cta { color: #fff !important; }

.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: 0;
  padding: 8px;
  cursor: pointer;
}
.nav__toggle span {
  width: 22px; height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform .25s ease, opacity .2s ease;
}

/* ---------- Hero ---------- */
.hero {
  background:
    radial-gradient(1200px 500px at 85% -10%, rgba(246, 41, 42, .08), transparent 60%),
    var(--bg);
  padding: clamp(48px, 8vw, 96px) 0 clamp(40px, 6vw, 72px);
  overflow: hidden;
}
.hero__inner {
  display: grid;
  grid-template-columns: 1.05fr .95fr;
  align-items: center;
  gap: 48px;
}
.eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 500;
  color: var(--brand-red);
  letter-spacing: .4px;
  margin: 0 0 14px;
  text-transform: uppercase;
}
.hero__title {
  font-size: clamp(34px, 5.4vw, 56px);
  line-height: 1.12;
  font-weight: 600;
  margin: 0 0 20px;
  letter-spacing: -.5px;
}
.hero__title .accent { color: var(--brand-red); }
.hero__lead {
  font-size: clamp(16px, 1.6vw, 18px);
  color: var(--ink-2);
  margin: 0 0 28px;
  max-width: 30em;
}
.hero__lead strong { color: var(--ink); font-weight: 600; }
.hero__actions { display: flex; flex-wrap: wrap; gap: 12px; }
.hero__badges {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  padding: 0;
  margin: 28px 0 0;
  color: var(--ink-2);
  font-size: 14px;
}

.hero__visual {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 420px;
}
.phone {
  width: clamp(240px, 28vw, 320px);
  border-radius: 28px;
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-soft);
  transform: rotate(-2deg);
}
.phone img { width: 100%; height: auto; }

/* ---------- 通用 section ---------- */
.section { padding: clamp(56px, 8vw, 96px) 0; }
.section--alt { background: var(--bg); }
.section__head { max-width: 680px; margin: 0 auto clamp(36px, 5vw, 56px); text-align: center; }
.section__title {
  font-size: clamp(26px, 3.4vw, 38px);
  font-weight: 600;
  margin: 0 0 14px;
  letter-spacing: -.3px;
}
.section__sub { color: var(--ink-2); margin: 0; font-size: 16px; }

/* ---------- 功能卡片 ---------- */
.grid { display: grid; gap: 20px; }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 26px 24px;
  box-shadow: var(--shadow-card);
  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}
.card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-soft);
  border-color: #dcdde0;
}
.card__icon {
  font-size: 22px;
  width: 46px; height: 46px;
  display: grid; place-items: center;
  background: var(--bg);
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
}
.card__title { font-size: 18px; font-weight: 600; margin: 0 0 8px; }
.card__text { color: var(--ink-2); font-size: 15px; margin: 0; }

/* ---------- 界面展示 ---------- */
.gallery {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.shot {
  margin: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  transition: transform .18s ease, box-shadow .18s ease;
}
.shot:hover { transform: translateY(-3px); box-shadow: var(--shadow-soft); }
.shot img { width: 100%; height: auto; background: var(--bg); }
.shot figcaption {
  padding: 14px 16px;
  font-size: 14px;
  color: var(--ink-2);
  border-top: 1px solid var(--border);
}

/* ---------- 下载 ---------- */
.download { text-align: center; }
.download__inner {
  background: var(--ink);
  color: #fff;
  border-radius: var(--radius-lg);
  padding: clamp(40px, 6vw, 64px) 24px;
  position: relative;
  overflow: hidden;
}
.download__inner::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(600px 300px at 50% -20%, rgba(246,41,42,.35), transparent 60%);
}
.download__inner > * { position: relative; }
.download .section__title { color: #fff; }
.download .section__sub { color: rgba(255,255,255,.7); }
.download__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  justify-content: center;
  margin: 28px 0 18px;
}
.download__note { color: rgba(255,255,255,.55); font-size: 13px; margin: 0; }

/* ---------- 页脚 ---------- */
.footer { border-top: 1px solid var(--border); background: var(--surface); padding: 36px 0; }
.footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.footer__brand { display: inline-flex; align-items: center; gap: 8px; }
.footer__links { display: flex; gap: 22px; flex-wrap: wrap; }
.footer__links a { color: var(--ink-2); font-size: 14px; }
.footer__links a:hover { color: var(--ink); }
.footer__copy { width: 100%; color: var(--ink-3); font-size: 13px; margin: 4px 0 0; }

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .hero__inner { grid-template-columns: 1fr; gap: 32px; }
  .hero__visual { min-height: 360px; order: -1; }
  .grid--3 { grid-template-columns: repeat(2, 1fr); }
  .gallery { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 720px) {
  .nav__links {
    position: fixed;
    inset: 64px 0 auto 0;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 16px var(--pad) 22px;
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition: transform .22s ease, opacity .22s ease;
    box-shadow: var(--shadow-soft);
  }
  .nav__links.is-open { transform: translateY(0); opacity: 1; pointer-events: auto; }
  .nav__links a { padding: 12px 4px; font-size: 16px; }
  .nav__cta { margin-top: 8px; text-align: center; }
  .nav__toggle { display: flex; }
  .nav__toggle.is-active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav__toggle.is-active span:nth-child(2) { opacity: 0; }
  .nav__toggle.is-active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
}

@media (max-width: 560px) {
  .grid--3 { grid-template-columns: 1fr; }
  .gallery { grid-template-columns: repeat(2, 1fr); }
  .hero__badges { gap: 12px; }
  .brand__cn { display: none; }
}

/* 尊重用户的减少动效偏好 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; animation: none !important; }
}