/* CC商聊 官网 —— 极简下载页 */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root{
  --ink:#1B1D20;
  --ink-2:#606366;
  --ink-3:#8E9299;
  --line:#F1F5F9;
  --card:#24272C;
  --card-hover:#2A2E34;
  --card-line:#383C44;
  --page:#F8FAFC;
}

html, body { -webkit-text-size-adjust: 100%; }
body{
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
               "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--page);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
a { text-decoration: none; color: inherit; }
img { display: block; }

/* ---------- 顶部导航 ---------- */
.site-header{
  position: fixed; top: 0; left: 0; right: 0;
  height: 84px; z-index: 30;
  display: flex; align-items: center;
  background: #fff;
  border-bottom: 1px solid var(--line);
  box-shadow: 0 1px 3px rgba(0,0,0,.015);
  user-select: none;
}
.site-header .inner{
  width: 100%; max-width: 1440px; margin: 0 auto;
  padding: 0 48px;
  display: flex; align-items: center; gap: 10px;
}
.site-header img{
  width: 48px; height: 48px;
  border-radius: 12px;
  object-fit: contain;
}
.site-header .brand{
  font-size: 20px; font-weight: 700;
  letter-spacing: .5px; color: var(--ink);
}

/* ---------- 首屏 ---------- */
main{ position: relative; min-height: 100vh; overflow-x: hidden; }

.bg-layer{
  position: absolute; left: 0; right: 0; top: 84px; bottom: 0;
  overflow: hidden; pointer-events: none; z-index: 0;
}
.bg-layer img{
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  object-fit: cover;
}
.bg-layer .bg-mobile{ object-position: top center; display: none; }

.hero{
  position: relative; z-index: 10;
  min-height: 100vh;
  margin-top: 84px;
  padding: 56px 48px 64px;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
}

.hero h1{
  font-size: 48px; font-weight: 400;
  letter-spacing: 1px; line-height: 1.3;
  text-align: center;
  display: flex; align-items: center; justify-content: center;
  flex-wrap: wrap; gap: 0 6px;
}
.hero h1 b{ font-weight: 800; }
.hero h1 .star{
  width: 30px; height: 30px; margin: 0 6px;
  display: inline-block; vertical-align: middle;
  animation: spin 9s linear infinite;
}
@keyframes spin{ to{ transform: rotate(360deg); } }

.hero .sub{
  margin-top: 16px;
  font-size: 18px; font-weight: 400;
  color: var(--ink-2);
  letter-spacing: .03em; line-height: 1.9;
  text-align: center;
}
.hero .sub b{ font-weight: 800; color: var(--ink); }
.hero .sub .sep{ color: #D0D3D6; margin: 0 6px; }

/* ---------- 下载卡片 ---------- */
.cards{
  width: 100%; max-width: 1184px;
  margin-top: 120px;
  display: flex; flex-wrap: nowrap;
  align-items: flex-end; justify-content: center;
  gap: 24px;
}

.card{
  position: relative;
  width: 262px; height: 108px;
  background: var(--card);
  border: 1px solid var(--card-line);
  border-radius: 20px;
  overflow: hidden;
  cursor: pointer;
  transition: height .3s ease, background .3s ease, box-shadow .3s ease;
  flex: 0 0 auto;
}
.card:hover, .card.open{
  height: 192px;
  background: var(--card-hover);
  box-shadow: 0 16px 36px rgba(0,0,0,.3);
}

.card .face,
.card .panel{
  position: absolute; inset: 0;
  transition: opacity .3s ease;
}
.card .face{
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  gap: 8px; padding: 0 16px; text-align: center;
}
.card:hover .face, .card.open .face{ opacity: 0; pointer-events: none; }

.card .panel{
  opacity: 0; pointer-events: none;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  gap: 8px; padding: 0 16px; text-align: center;
}
.card:hover .panel, .card.open .panel{ opacity: 1; pointer-events: auto; }

.card .row{
  display: flex; align-items: center; justify-content: center; gap: 12px;
  user-select: none;
}
.card .ico{ width: 34px; height: 34px; display: flex; align-items: center; justify-content: center; }
.card .ico img{ width: 34px; height: 34px; object-fit: contain; }
.card .name{
  font-size: 19px; font-weight: 700; color: #fff;
  letter-spacing: .5px; line-height: 1;
  white-space: nowrap;
}
.card .hint{
  font-size: 11px; color: var(--ink-3);
  line-height: 1.4; margin-top: 4px;
  white-space: nowrap;
}

.card .qr-box{
  width: 110px; height: 110px;
  background: #fff; border-radius: 12px;
  padding: 8px; display: flex; align-items: center; justify-content: center;
  box-shadow: 0 1px 2px rgba(0,0,0,.06);
}
.card .qr-box img{ width: 100%; height: 100%; object-fit: contain; user-select: none; }
.card .qr-tip{ font-size: 11px; color: var(--ink-3); margin-top: 6px; }

/* 电脑版卡片：悬停给小提示 */
.card .big-ico{ width: 56px; height: 56px; display: flex; align-items: center; justify-content: center; }
.card .big-ico img{ width: 56px; height: 56px; object-fit: contain; }
.card .panel .name{ font-size: 16px; }

/* ---------- 下滑提示 ---------- */
.scroll-tip{
  margin-top: 72px;
  display: flex; flex-direction: column; align-items: center; gap: 8px;
  font-size: 13px; color: #9AA0A6; letter-spacing: .5px;
}
.scroll-tip .bar{
  width: 40px; height: 3px; border-radius: 2px; background: #D8DDE3;
}
.scroll-tip .chev{
  width: 10px; height: 10px; margin-top: -2px;
  border-right: 2px solid #C3C9D0; border-bottom: 2px solid #C3C9D0;
  transform: rotate(45deg);
  animation: bob 1.6s ease-in-out infinite;
}
@keyframes bob{ 0%,100%{ transform: rotate(45deg) translate(0,0); } 50%{ transform: rotate(45deg) translate(3px,3px); } }

/* ---------- 安装教程 ---------- */
.guide{
  position: relative; z-index: 10;
  background: #fff;
  border-top: 1px solid var(--line);
  padding: 72px 48px 88px;
}
.guide .inner{ max-width: 1184px; margin: 0 auto; }
.guide h2{
  font-size: 30px; font-weight: 800; letter-spacing: .5px;
  text-align: center; margin-bottom: 10px;
}
.guide .lead{
  text-align: center; color: var(--ink-2);
  font-size: 15px; margin-bottom: 44px;
}
.steps{
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px;
}
.step{
  background: #F8FAFC;
  border: 1px solid #EDF1F5;
  border-radius: 20px;
  padding: 28px 24px;
}
.step .no{
  width: 30px; height: 30px; border-radius: 9px;
  background: #24272C; color: #fff;
  font-size: 14px; font-weight: 700;
  display: flex; align-items: center; justify-content: center;
  margin-bottom: 16px;
}
.step h3{ font-size: 17px; font-weight: 700; margin-bottom: 10px; }
.step p{ font-size: 14px; color: var(--ink-2); line-height: 1.85; }
.step p + p{ margin-top: 6px; }
.step em{ font-style: normal; font-weight: 700; color: var(--ink); }

.btn-row{
  margin-top: 40px;
  display: flex; gap: 14px; justify-content: center; flex-wrap: wrap;
}
.btn{
  height: 54px; padding: 0 34px;
  border-radius: 16px;
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  font-size: 15px; font-weight: 700;
  transition: transform .18s ease, box-shadow .18s ease, background .18s ease;
}
.btn:active{ transform: translateY(1px); }
.btn-primary{
  background: #24272C; color: #fff;
  box-shadow: 0 8px 20px rgba(36,39,44,.22);
}
.btn-primary:hover{ background: #31353B; box-shadow: 0 12px 26px rgba(36,39,44,.28); }
.btn-ghost{
  background: #fff; color: var(--ink);
  border: 1px solid #E3E8EE;
}
.btn-ghost:hover{ background: #F6F8FB; }
.btn img{ width: 20px; height: 20px; object-fit: contain; }

.site-footer{
  background: #fff;
  border-top: 1px solid var(--line);
  padding: 28px 48px 40px;
  text-align: center;
  color: #9AA0A6; font-size: 12.5px; line-height: 2;
}
.site-footer a{ color: #6B7280; }
.site-footer a:hover{ color: var(--ink); }

/* ---------- 响应式 ---------- */
@media (max-width: 1100px){
  .cards{ flex-wrap: wrap; margin-top: 96px; }
  .cards{ max-width: 860px; }
}

@media (max-width: 768px){
  .site-header{ height: 60px; }
  .site-header .inner{ padding: 0 18px; gap: 8px; }
  .site-header img{ width: 34px; height: 34px; border-radius: 9px; }
  .site-header .brand{ font-size: 17px; }

  .bg-layer{ top: 60px; }
  .bg-layer .bg-pc{ display: none; }
  .bg-layer .bg-mobile{ display: block; }

  .hero{
    margin-top: 60px;
    min-height: calc(100vh - 60px);
    min-height: calc(100svh - 60px);
    padding: 30px 22px 30px;
    justify-content: center;
  }
  .hero h1{
    font-size: 24px; line-height: 1.5;
    gap: 0 2px; letter-spacing: 0;
  }
  .hero h1 > span{ white-space: nowrap; }
  .hero h1 .star{ width: 18px; height: 18px; margin: 0 3px; }
  .hero .sub{
    margin-top: 14px; font-size: 13.5px; line-height: 1.95;
  }
  .hero .sub .sep{ display: inline; margin: 0 5px; }
  .hero .sub .br-sep{ display: none; }
  .hero .sub br.m{ display: block; }

  .cards{
    margin-top: 36px;
    flex-direction: column; align-items: stretch;
    gap: 12px; max-width: 420px;
  }
  .card{
    width: 100%; height: 64px; border-radius: 16px;
  }
  .card .name{ font-size: 16px; }
  .card .ico, .card .ico img{ width: 26px; height: 26px; }
  .card:hover, .card.open{ height: 168px; }
  .card .qr-box{ width: 96px; height: 96px; }
  .card .hint{ font-size: 10.5px; }

  .scroll-tip{ margin-top: 42px; padding-top: 0; font-size: 12px; }

  .guide{ padding: 48px 20px 56px; }
  .guide h2{ font-size: 22px; }
  .guide .lead{ font-size: 13.5px; margin-bottom: 28px; }
  .steps{ grid-template-columns: 1fr; gap: 14px; }
  .step{ padding: 22px 20px; border-radius: 16px; }
  .btn-row{ display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
  .btn{ height: 50px; padding: 0 14px; font-size: 14px; }
  .btn-pc{ grid-column: 1 / -1; }
  .site-footer{ padding: 22px 20px 32px; }
}

@media (prefers-reduced-motion: reduce){
  *{ animation: none !important; transition: none !important; }
}

/* ---------- 卡片改为「点击下载」（去掉二维码面板） ---------- */
.card,
.card:hover,
.card.open{
  height: 112px !important;
  box-shadow: none;
  transform: none;
  transition: transform .25s ease, box-shadow .25s ease, background .25s ease, border-color .25s ease;
}
.card:hover{
  height: 112px !important;
  transform: translateY(-4px);
  box-shadow: 0 16px 36px rgba(0,0,0,.28);
  background: var(--card-hover);
}
.card .face{
  opacity: 1 !important;
  pointer-events: auto !important;
  gap: 12px;
}
.card .panel{ display: none !important; }
.card .hint{
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  margin-top: 0; padding: 7px 18px;
  font-size: 12.5px; font-weight: 600; letter-spacing: .4px;
  color: #E7E8EE; background: rgba(255,255,255,.08);
  border: 1px solid rgba(255,255,255,.15);
  border-radius: 999px; white-space: nowrap;
  transition: background .25s ease, color .25s ease, border-color .25s ease;
}
.card .hint svg{ width: 13px; height: 13px; display: block; }
.card:hover .hint{
  background: #fff; color: #1B1D20; border-color: #fff;
}
.card .hint.soon,
.card:hover .hint.soon{
  color: #9AA0A6; background: transparent; border-color: rgba(255,255,255,.08);
}
.card.is-soon{ cursor: default; }

@media (max-width: 768px){
  .card,
  .card:hover,
  .card.open{ height: 66px !important; transform: none; box-shadow: none; }
  .card .face{
    flex-direction: row; justify-content: space-between;
    padding: 0 16px 0 18px; gap: 10px;
  }
  .card .row{ gap: 10px; }
  .card .hint{ font-size: 12px; padding: 6px 14px; }
}