/* =========================================================
   一起草 · 植物视频社区  ——  共享设计系统
   现代 / 可爱 / 大气 / 专业
   主色：活力植物绿  渐变：绿→青  强调：阳光橙 / 嫩芽绿
   ========================================================= */

/* ---------- 设计令牌 ---------- */
:root {
  /* 品牌色 */
  --brand:        #1DB95A;
  --brand-deep:   #0F8F44;
  --brand-soft:   #E8F8EE;
  --accent:       #FF8C42;
  --accent-deep:  #E0741F;
  --accent-2:     #7ED957;

  /* 中性色 */
  --ink:          #0F3D2E;
  --ink-soft:     #4A6B5C;
  --ink-mute:     #7C8C84;
  --bg:           #F4FAF6;
  --bg-2:         #EAF5EE;
  --surface:      #FFFFFF;
  --border:       #E2EEE5;
  --border-soft:  #EEF5EF;

  /* 渐变 */
  --grad-brand:   linear-gradient(135deg, #1DB95A 0%, #00C9A7 100%);
  --grad-sun:     linear-gradient(135deg, #FF8C42 0%, #FFB347 100%);
  --grad-leaf:    linear-gradient(135deg, #7ED957 0%, #1DB95A 100%);
  --grad-deep:    linear-gradient(160deg, #0F3D2E 0%, #0F8F44 100%);
  --grad-hero:    linear-gradient(135deg, #0F3D2E 0%, #0F8F44 55%, #1DB95A 100%);

  /* 圆角 */
  --r-sm: 10px;
  --r-md: 16px;
  --r-lg: 24px;
  --r-xl: 32px;
  --r-pill: 999px;

  /* 阴影 */
  --sh-sm: 0 2px 8px rgba(15, 61, 46, 0.06);
  --sh-md: 0 8px 24px rgba(15, 61, 46, 0.08);
  --sh-lg: 0 20px 48px rgba(15, 61, 46, 0.12);
  --sh-brand: 0 12px 32px rgba(29, 185, 90, 0.28);
  --sh-sun:   0 12px 32px rgba(255, 140, 66, 0.30);

  /* 间距尺度 */
  --sp-1: 4px;
  --sp-2: 8px;
  --sp-3: 12px;
  --sp-4: 16px;
  --sp-5: 24px;
  --sp-6: 32px;
  --sp-7: 48px;
  --sp-8: 64px;
  --sp-9: 96px;

  /* 布局 */
  --container: 1200px;
  --nav-h: 72px;

  /* 动效 */
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);

  /* 字体 */
  --font: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
  font-size: 16px;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
input { font-family: inherit; }

/* ---------- 容器 ---------- */
.container { width: 100%; max-width: var(--container); margin: 0 auto; padding: 0 var(--sp-5); }

/* ---------- 排版 ---------- */
h1, h2, h3, h4, h5 { line-height: 1.25; color: var(--ink); font-weight: 800; letter-spacing: -0.01em; }
h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); }
h2 { font-size: clamp(1.6rem, 3.5vw, 2.4rem); }
h3 { font-size: clamp(1.2rem, 2.4vw, 1.6rem); }
p  { color: var(--ink-soft); }

.eyebrow {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 0.82rem; font-weight: 700; letter-spacing: 0.04em;
  color: var(--brand-deep); background: var(--brand-soft);
  padding: 6px 14px; border-radius: var(--r-pill); text-transform: uppercase;
}
.eyebrow.sun { color: var(--accent-deep); background: #FFF0E6; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 24px; border-radius: var(--r-pill); font-weight: 700; font-size: 1rem;
  transition: transform .25s var(--ease-out), box-shadow .25s var(--ease-out), background .25s;
  white-space: nowrap; border: 2px solid transparent;
}
.btn:active { transform: scale(0.97); }
.btn-primary { background: var(--grad-brand); color: #fff; box-shadow: var(--sh-brand); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 16px 40px rgba(29,185,90,.4); }
.btn-sun { background: var(--grad-sun); color: #fff; box-shadow: var(--sh-sun); }
.btn-sun:hover { transform: translateY(-2px); box-shadow: 0 16px 40px rgba(255,140,66,.42); }
.btn-ghost { background: #fff; color: var(--ink); border-color: var(--border); box-shadow: var(--sh-sm); }
.btn-ghost:hover { border-color: var(--brand); color: var(--brand-deep); transform: translateY(-2px); }
.btn-light { background: rgba(255,255,255,.16); color: #fff; border-color: rgba(255,255,255,.4); backdrop-filter: blur(8px); }
.btn-light:hover { background: rgba(255,255,255,.28); transform: translateY(-2px); }
.btn-lg { padding: 16px 32px; font-size: 1.08rem; }
.btn-sm { padding: 8px 18px; font-size: 0.9rem; }
.btn-block { display: flex; width: 100%; }

/* ---------- 导航栏 ---------- */
.nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,0.82); backdrop-filter: saturate(180%) blur(16px);
  border-bottom: 1px solid var(--border-soft);
  transition: box-shadow .3s var(--ease), background .3s;
}
.nav.scrolled { box-shadow: var(--sh-md); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: var(--nav-h); }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 900; font-size: 1.3rem; color: var(--ink); }
.brand-logo {
  width: 38px; height: 38px; border-radius: 12px; background: var(--grad-brand);
  display: grid; place-items: center; color: #fff; box-shadow: var(--sh-brand); flex-shrink: 0;
}
.brand-logo svg { width: 22px; height: 22px; }
.brand b { color: var(--brand-deep); }

.nav-links { display: flex; align-items: center; gap: 4px; }
.nav-links a {
  padding: 8px 16px; border-radius: var(--r-pill); font-weight: 600; font-size: 0.95rem;
  color: var(--ink-soft); transition: all .2s;
}
.nav-links a:hover { color: var(--brand-deep); background: var(--brand-soft); }
.nav-links a.active { color: var(--brand-deep); background: var(--brand-soft); }

.nav-cta { display: flex; align-items: center; gap: 10px; }

.nav-toggle { display: none; width: 42px; height: 42px; border-radius: 12px; place-items: center; color: var(--ink); }
.nav-toggle:hover { background: var(--brand-soft); }
.nav-toggle svg { width: 24px; height: 24px; }
.nav-toggle .ic-close { display: none; }
.nav-toggle.open .ic-menu { display: none; }
.nav-toggle.open .ic-close { display: block; }

/* 移动端抽屉 */
.mobile-menu {
  position: fixed; inset: var(--nav-h) 0 auto 0; background: #fff; z-index: 99;
  padding: var(--sp-5); display: none; flex-direction: column; gap: var(--sp-2);
  box-shadow: var(--sh-lg); transform: translateY(-12px); opacity: 0;
  transition: transform .3s var(--ease-out), opacity .3s;
}
.mobile-menu.open { display: flex; transform: translateY(0); opacity: 1; }
.mobile-menu a { padding: 14px 16px; border-radius: var(--r-md); font-weight: 600; font-size: 1.05rem; color: var(--ink); }
.mobile-menu a:hover { background: var(--brand-soft); }
.mobile-menu .btn { margin-top: var(--sp-3); }

/* ---------- Hero 通用 ---------- */
.hero { position: relative; overflow: hidden; }
.hero-bg {
  position: absolute; inset: 0; z-index: 0;
  background: var(--grad-hero);
}
.hero-bg::after {
  content: ""; position: absolute; inset: 0;
  background-image:
    radial-gradient(circle at 18% 22%, rgba(255,255,255,.16) 0, transparent 38%),
    radial-gradient(circle at 82% 30%, rgba(126,217,87,.30) 0, transparent 42%),
    radial-gradient(circle at 60% 88%, rgba(0,201,167,.22) 0, transparent 45%);
}
/* 浮动叶子装饰 */
.leaf {
  position: absolute; z-index: 1; pointer-events: none; opacity: .5;
  color: rgba(255,255,255,.35);
}
.leaf svg { width: 100%; height: 100%; filter: drop-shadow(0 6px 14px rgba(0,0,0,.12)); }
.leaf.l1 { top: 12%; right: 8%; width: 90px; height: 90px; transform: rotate(25deg); animation: float1 7s ease-in-out infinite; }
.leaf.l2 { top: 60%; right: 18%; width: 60px; height: 60px; transform: rotate(-20deg); animation: float2 9s ease-in-out infinite; }
.leaf.l3 { bottom: 8%; left: 5%; width: 70px; height: 70px; transform: rotate(40deg); animation: float1 8s ease-in-out infinite reverse; }
@keyframes float1 { 0%,100% { transform: rotate(25deg) translateY(0); } 50% { transform: rotate(35deg) translateY(-18px); } }
@keyframes float2 { 0%,100% { transform: rotate(-20deg) translateY(0); } 50% { transform: rotate(-10deg) translateY(14px); } }

.hero-content { position: relative; z-index: 2; padding: var(--sp-9) 0 var(--sp-8); color: #fff; }
.hero-content h1, .hero-content h2, .hero-content h3 { color: #fff; }
.hero-content p { color: rgba(255,255,255,.85); }
.hero-content .eyebrow { background: rgba(255,255,255,.18); color: #fff; backdrop-filter: blur(8px); }

/* ---------- 区块通用 ---------- */
.section { padding: var(--sp-8) 0; }
.section-head { text-align: center; max-width: 680px; margin: 0 auto var(--sp-6); }
.section-head h2 { margin: var(--sp-3) 0; }
.section-head p { color: var(--ink-soft); font-size: 1.05rem; }
.section.alt { background: var(--bg-2); }

/* ---------- 数据大字报 ---------- */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--sp-5); }
.stat {
  background: var(--surface); border: 1px solid var(--border-soft); border-radius: var(--r-lg);
  padding: var(--sp-6) var(--sp-5); text-align: center; box-shadow: var(--sh-sm);
  transition: transform .3s var(--ease-out), box-shadow .3s; position: relative; overflow: hidden;
}
.stat:hover { transform: translateY(-6px); box-shadow: var(--sh-lg); }
.stat::before {
  content: ""; position: absolute; top: 0; left: 0; right: 0; height: 4px; background: var(--grad-brand);
}
.stat .num { font-size: clamp(2rem, 4vw, 3rem); font-weight: 900; color: var(--brand-deep); line-height: 1; }
.stat .num .unit { font-size: 0.5em; color: var(--ink-soft); margin-left: 2px; }
.stat .label { margin-top: 10px; font-weight: 600; color: var(--ink); }
.stat .desc { font-size: 0.85rem; color: var(--ink-mute); margin-top: 4px; }

/* ---------- 视频卡片 ---------- */
.grid-videos { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: var(--sp-5); }
.card-video {
  background: var(--surface); border: 1px solid var(--border-soft); border-radius: var(--r-lg);
  overflow: hidden; box-shadow: var(--sh-sm); transition: transform .3s var(--ease-out), box-shadow .3s;
  display: flex; flex-direction: column;
}
.card-video:hover { transform: translateY(-8px); box-shadow: var(--sh-lg); }
.thumb {
  position: relative; aspect-ratio: 9/14; overflow: hidden;
  display: grid; place-items: center; color: #fff;
}
.thumb .ph { width: 100%; height: 100%; object-fit: cover; }
.thumb .play {
  position: absolute; width: 56px; height: 56px; border-radius: 50%; background: rgba(255,255,255,.92);
  display: grid; place-items: center; color: var(--brand-deep); box-shadow: var(--sh-md);
  transition: transform .3s var(--ease-out);
}
.thumb .play svg { width: 24px; height: 24px; margin-left: 3px; }
.card-video:hover .thumb .play { transform: scale(1.12); background: var(--brand); color: #fff; }
.thumb .tag {
  position: absolute; top: 12px; left: 12px; font-size: 0.75rem; font-weight: 700;
  background: rgba(0,0,0,.55); color: #fff; padding: 4px 10px; border-radius: var(--r-pill); backdrop-filter: blur(6px);
}
.thumb .dur { position: absolute; bottom: 12px; right: 12px; font-size: 0.75rem; font-weight: 600; color: #fff; background: rgba(0,0,0,.55); padding: 3px 8px; border-radius: var(--r-sm); }
.card-video .body { padding: var(--sp-4); display: flex; flex-direction: column; gap: 10px; flex: 1; }
.card-video h3 { font-size: 1.05rem; line-height: 1.4; }
.card-video .meta { display: flex; align-items: center; gap: 12px; font-size: 0.82rem; color: var(--ink-mute); margin-top: auto; padding-top: 8px; border-top: 1px solid var(--border-soft); }
.card-video .meta span { display: flex; align-items: center; gap: 4px; }
.card-video .meta svg { width: 14px; height: 14px; }
.card-video .author { display: flex; align-items: center; gap: 8px; font-size: 0.85rem; font-weight: 600; color: var(--ink-soft); }
.avatar { width: 28px; height: 28px; border-radius: 50%; background: var(--grad-leaf); display: grid; place-items: center; color: #fff; font-size: 0.75rem; font-weight: 700; flex-shrink: 0; }

/* ---------- 筛选 Chips ---------- */
.chips { display: flex; flex-wrap: wrap; gap: 10px; }
.chip {
  padding: 8px 18px; border-radius: var(--r-pill); font-weight: 600; font-size: 0.9rem;
  background: var(--surface); color: var(--ink-soft); border: 1px solid var(--border);
  transition: all .2s;
}
.chip:hover { border-color: var(--brand); color: var(--brand-deep); }
.chip.active { background: var(--grad-brand); color: #fff; border-color: transparent; box-shadow: var(--sh-brand); }

/* ---------- 通用卡片 ---------- */
.card { background: var(--surface); border: 1px solid var(--border-soft); border-radius: var(--r-lg); padding: var(--sp-5); box-shadow: var(--sh-sm); transition: transform .3s var(--ease-out), box-shadow .3s; }
.card:hover { transform: translateY(-4px); box-shadow: var(--sh-lg); }

/* ---------- 特性卡 ---------- */
.feature { display: flex; flex-direction: column; gap: var(--sp-3); }
.feature .ic {
  width: 56px; height: 56px; border-radius: var(--r-md); display: grid; place-items: center; color: #fff;
  box-shadow: var(--sh-sm); flex-shrink: 0;
}
.feature .ic svg { width: 28px; height: 28px; }
.feature h3 { margin-bottom: 6px; }

/* ---------- 排行榜 ---------- */
.rank-row {
  display: flex; align-items: center; gap: var(--sp-4); padding: var(--sp-4);
  background: var(--surface); border: 1px solid var(--border-soft); border-radius: var(--r-md);
  transition: transform .2s, box-shadow .2s; box-shadow: var(--sh-sm);
}
.rank-row:hover { transform: translateX(6px); box-shadow: var(--sh-md); }
.rank-num { width: 40px; height: 40px; border-radius: 12px; display: grid; place-items: center; font-weight: 900; font-size: 1.2rem; color: #fff; flex-shrink: 0; }
.rank-num.r1 { background: linear-gradient(135deg,#FFD24D,#FF8C42); }
.rank-num.r2 { background: linear-gradient(135deg,#C5D0DA,#8B9AA8); }
.rank-num.r3 { background: linear-gradient(135deg,#E8A06B,#C77F4A); }
.rank-num.other { background: var(--ink-mute); }
.rank-info { flex: 1; min-width: 0; }
.rank-info h4 { font-size: 1rem; }
.rank-info .sub { font-size: 0.82rem; color: var(--ink-mute); }
.rank-votes { text-align: right; flex-shrink: 0; }
.rank-votes b { font-size: 1.1rem; color: var(--brand-deep); }
.rank-votes small { display: block; font-size: 0.72rem; color: var(--ink-mute); }

/* ---------- 步骤 ---------- */
.steps { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: var(--sp-5); counter-reset: step; }
.step { position: relative; padding: var(--sp-6) var(--sp-5); background: var(--surface); border: 1px solid var(--border-soft); border-radius: var(--r-lg); box-shadow: var(--sh-sm); }
.step::before { counter-increment: step; content: counter(step); position: absolute; top: -16px; left: var(--sp-5); width: 40px; height: 40px; border-radius: 12px; background: var(--grad-brand); color: #fff; display: grid; place-items: center; font-weight: 900; font-size: 1.2rem; box-shadow: var(--sh-brand); }
.step h3 { margin: var(--sp-2) 0 6px; font-size: 1.1rem; }

/* ---------- 下载区 ---------- */
.download-grid { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: var(--sp-7); align-items: center; }
.phone-mock {
  position: relative; width: 280px; aspect-ratio: 9/18; margin: 0 auto;
  background: var(--ink); border-radius: 36px; padding: 10px; box-shadow: var(--sh-lg);
}
.phone-mock::before { content: ""; position: absolute; top: 18px; left: 50%; transform: translateX(-50%); width: 80px; height: 24px; background: var(--ink); border-radius: var(--r-pill); z-index: 3; }
.phone-screen { width: 100%; height: 100%; border-radius: 28px; background: var(--grad-hero); overflow: hidden; display: flex; flex-direction: column; justify-content: center; align-items: center; color: #fff; gap: 16px; }
.phone-screen .logo-big { width: 72px; height: 72px; border-radius: 20px; background: var(--grad-sun); display: grid; place-items: center; box-shadow: var(--sh-sun); }
.qr-box { background: #fff; border-radius: var(--r-md); padding: var(--sp-5); text-align: center; box-shadow: var(--sh-md); }
.qr { width: 180px; height: 180px; margin: 0 auto var(--sp-3); background:
  linear-gradient(45deg, #0F3D2E 25%, transparent 25%) 0 0/16px 16px,
  linear-gradient(-45deg, #0F3D2E 25%, transparent 25%) 0 0/16px 16px,
  linear-gradient(45deg, transparent 75%, #0F3D2E 75%) 0 0/16px 16px,
  linear-gradient(-45deg, transparent 75%, #0F3D2E 75%) 0 0/16px 16px,
  #fff; border: 8px solid #fff; border-radius: 12px;
}

/* ---------- FAQ ---------- */
.faq-item { border: 1px solid var(--border-soft); border-radius: var(--r-md); background: var(--surface); margin-bottom: 12px; overflow: hidden; box-shadow: var(--sh-sm); }
.faq-q { width: 100%; text-align: left; padding: var(--sp-4) var(--sp-5); font-weight: 700; font-size: 1.02rem; color: var(--ink); display: flex; justify-content: space-between; align-items: center; gap: 16px; }
.faq-q .chev { transition: transform .3s; flex-shrink: 0; color: var(--brand-deep); }
.faq-q .chev svg { width: 20px; height: 20px; }
.faq-item.open .faq-q .chev { transform: rotate(180deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height .35s var(--ease); }
.faq-a-inner { padding: 0 var(--sp-5) var(--sp-4); color: var(--ink-soft); }

/* ---------- 弹窗 ---------- */
.modal-mask {
  position: fixed; inset: 0; z-index: 200; background: rgba(15,61,46,.55); backdrop-filter: blur(4px);
  display: none; align-items: center; justify-content: center; padding: var(--sp-5);
  opacity: 0; transition: opacity .25s;
}
.modal-mask.open { display: flex; opacity: 1; }
.modal {
  background: #fff; border-radius: var(--r-xl); padding: var(--sp-6); max-width: 560px; width: 100%;
  box-shadow: var(--sh-lg); transform: scale(.9) translateY(20px); transition: transform .3s var(--ease-out);
  position: relative; max-height: 90vh; overflow-y: auto;
}
.modal-mask.open .modal { transform: scale(1) translateY(0); }
.modal .modal-close { position: absolute; top: 16px; right: 16px; width: 36px; height: 36px; border-radius: 50%; display: grid; place-items: center; color: var(--ink-mute); background: var(--bg-2); }
.modal .modal-close:hover { background: var(--brand-soft); color: var(--brand-deep); }
.modal h3 { margin-bottom: var(--sp-3); }

/* ---------- 回到顶部 ---------- */
.back-top {
  position: fixed; right: 24px; bottom: 24px; width: 50px; height: 50px; border-radius: 14px;
  background: var(--grad-brand); color: #fff; display: grid; place-items: center; box-shadow: var(--sh-brand);
  z-index: 90; opacity: 0; visibility: hidden; transform: translateY(20px) scale(.8); transition: all .3s var(--ease-out);
}
.back-top.show { opacity: 1; visibility: visible; transform: translateY(0) scale(1); }
.back-top:hover { transform: translateY(-4px) scale(1.05); }
.back-top svg { width: 24px; height: 24px; }

/* ---------- 浮动下载条 ---------- */
.float-dl {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 80;
  background: rgba(255,255,255,.92); backdrop-filter: blur(16px); border-top: 1px solid var(--border-soft);
  box-shadow: 0 -8px 32px rgba(15,61,46,.08); padding: 12px 0; transform: translateY(100%); transition: transform .35s var(--ease-out);
}
.float-dl.show { transform: translateY(0); }
.float-dl-inner { display: flex; align-items: center; justify-content: center; gap: var(--sp-4); }
.float-dl-text { font-weight: 700; color: var(--ink); }
.float-dl-text small { display: block; font-weight: 500; font-size: 0.78rem; color: var(--ink-mute); }

/* ---------- 页脚 ---------- */
.footer { background: var(--grad-deep); color: rgba(255,255,255,.8); padding: var(--sp-7) 0 var(--sp-5); position: relative; overflow: hidden; }
.footer::before { content: ""; position: absolute; top: 0; left: 0; right: 0; height: 60px; background: linear-gradient(to bottom, rgba(255,255,255,.06), transparent); }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: var(--sp-6); position: relative; z-index: 1; }
.footer .brand { color: #fff; margin-bottom: var(--sp-3); }
.footer .brand b { color: var(--accent-2); }
.footer p { color: rgba(255,255,255,.65); font-size: 0.9rem; }
.footer h4 { color: #fff; font-size: 1rem; margin-bottom: var(--sp-3); }
.footer ul li { margin-bottom: 10px; }
.footer ul a { color: rgba(255,255,255,.7); font-size: 0.9rem; transition: color .2s; }
.footer ul a:hover { color: var(--accent-2); }
.footer-bottom { margin-top: var(--sp-6); padding-top: var(--sp-4); border-top: 1px solid rgba(255,255,255,.12); display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; font-size: 0.82rem; color: rgba(255,255,255,.5); }
.footer-bottom a { color: rgba(255,255,255,.5); }
.footer-bottom a:hover { color: var(--accent-2); }

/* ---------- 滚动显现动画 ---------- */
.reveal { opacity: 0; transform: translateY(30px); transition: opacity .7s var(--ease-out), transform .7s var(--ease-out); }
.reveal.visible { opacity: 1; transform: translateY(0); }
.reveal.d1 { transition-delay: .08s; }
.reveal.d2 { transition-delay: .16s; }
.reveal.d3 { transition-delay: .24s; }
.reveal.d4 { transition-delay: .32s; }

/* ---------- 工具类 ---------- */
.center { text-align: center; }
.mt-2 { margin-top: var(--sp-2); } .mt-3 { margin-top: var(--sp-3); } .mt-4 { margin-top: var(--sp-4); } .mt-5 { margin-top: var(--sp-5); } .mt-6 { margin-top: var(--sp-6); } .mt-7 { margin-top: var(--sp-7); }
.mb-3 { margin-bottom: var(--sp-3); } .mb-4 { margin-bottom: var(--sp-4); } .mb-5 { margin-bottom: var(--sp-5); } .mb-6 { margin-bottom: var(--sp-6); }
.grid-2 { display: grid; grid-template-columns: repeat(2,1fr); gap: var(--sp-5); }
.grid-3 { display: grid; grid-template-columns: repeat(3,1fr); gap: var(--sp-5); }
.grid-4 { display: grid; grid-template-columns: repeat(4,1fr); gap: var(--sp-5); }
.badge-hot { display: inline-flex; align-items: center; gap: 4px; font-size: 0.72rem; font-weight: 800; background: var(--grad-sun); color: #fff; padding: 3px 10px; border-radius: var(--r-pill); text-transform: uppercase; }
.text-brand { color: var(--brand-deep); }
.divider { height: 1px; background: var(--border); margin: var(--sp-5) 0; }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .stats { grid-template-columns: repeat(2,1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .download-grid { grid-template-columns: 1fr; gap: var(--sp-6); }
  .nav-links { display: none; }
  .nav-toggle { display: grid; }
  .float-dl { display: none !important; }
}
@media (max-width: 640px) {
  .section { padding: var(--sp-7) 0; }
  .hero-content { padding: var(--sp-7) 0 var(--sp-6); }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .stats { grid-template-columns: 1fr 1fr; gap: var(--sp-3); }
  .stat { padding: var(--sp-4); }
  .footer-grid { grid-template-columns: 1fr; gap: var(--sp-5); }
  .container { padding: 0 var(--sp-4); }
  .btn { padding: 10px 20px; font-size: 0.95rem; }
  .nav-cta .btn-ghost { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
  .reveal { opacity: 1; transform: none; }
}