/* ===== 变量与基础 ===== */
:root{
  --primary:#E84545;
  --primary-dark:#D43B3B;
  --primary-soft:#FCEBEB;
  --deep:#23262F;
  --deep-2:#2C303B;
  --bg:#F6F7F9;
  --card:#FFFFFF;
  --border:#ECEDF1;
  --text:#22242B;
  --text-2:#5B6070;
  --radius:16px;
  --shadow-sm:0 4px 16px rgba(35,38,47,.06);
  --shadow-hover:0 14px 30px rgba(35,38,47,.12);
  --maxw:1200px;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  font-family:"PingFang SC","Microsoft YaHei","Hiragino Sans GB","Helvetica Neue",Arial,sans-serif;
  color:var(--text);
  background:var(--bg);
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}
img{display:block;max-width:100%;height:auto}
button{font-family:inherit;border:none;background:none;cursor:pointer}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}
section{scroll-margin-top:76px}

/* ===== 按钮 ===== */
.btn{
  display:inline-flex;align-items:center;justify-content:center;
  padding:12px 28px;border-radius:999px;
  background:var(--primary);color:#fff;
  font-size:15px;font-weight:600;line-height:1;white-space:nowrap;
  transition:background .25s ease,transform .25s ease,box-shadow .25s ease;
}
.btn:hover{background:var(--primary-dark);transform:translateY(-2px);box-shadow:0 10px 22px rgba(232,69,69,.28)}
.btn-ghost{background:transparent;color:var(--primary);border:1.5px solid var(--primary)}
.btn-ghost:hover{background:var(--primary);color:#fff;box-shadow:0 10px 22px rgba(232,69,69,.28)}
.btn-lg{padding:14px 32px;font-size:16px}
.btn-nav{padding:8px 16px;font-size:13px}

/* ===== 顶部导航 ===== */
.header{
  position:fixed;top:0;left:0;right:0;z-index:100;
  background:rgba(255,255,255,.92);
  -webkit-backdrop-filter:blur(10px);
  backdrop-filter:blur(10px);
  border-bottom:1px solid var(--border);
  transition:box-shadow .3s ease;
}
.header.scrolled{box-shadow:0 6px 20px rgba(35,38,47,.08)}
.header-in{display:flex;align-items:center;height:64px;gap:24px}
.logo{font-size:20px;font-weight:800;letter-spacing:.5px;color:var(--text);white-space:nowrap}
.logo::before{content:"";display:inline-block;width:8px;height:8px;border-radius:50%;background:var(--primary);margin-right:8px;vertical-align:3px}
.nav{display:flex;align-items:center;gap:20px;margin:0 auto}
.nav a{font-size:14px;color:var(--text-2);transition:color .2s ease;white-space:nowrap}
.nav a:hover{color:var(--primary)}
.btn-nav{flex-shrink:0}

/* ===== Hero ===== */
.hero{
  background:linear-gradient(180deg,#FFFFFF 0%,var(--bg) 100%);
  padding:148px 0 84px;
}
.hero-in{display:grid;grid-template-columns:1.05fr .95fr;gap:56px;align-items:center}
.hero h1{font-size:40px;line-height:1.25;font-weight:800;letter-spacing:.5px}
.hero h1 .ver{
  display:inline-block;margin-left:10px;padding:4px 12px;border-radius:999px;
  background:var(--primary-soft);color:var(--primary);
  font-size:18px;font-weight:700;vertical-align:8px;
}
.hero-desc{margin-top:18px;font-size:16px;color:var(--text-2);line-height:1.9;max-width:520px}
.hero-btns{display:flex;gap:14px;margin-top:30px;flex-wrap:wrap}
.hero-img{display:flex;justify-content:flex-end}
.hero-img img{width:100%;max-width:400px;border-radius:20px;box-shadow:var(--shadow-hover)}

/* ===== 通用区块 ===== */
.section{padding:76px 0}
.section-alt{background:var(--card)}
.sec-title{font-size:30px;font-weight:800;text-align:center;letter-spacing:.5px}
.sec-title::after{content:"";display:block;width:44px;height:4px;border-radius:2px;background:var(--primary);margin:14px auto 0}
.sec-sub{margin-top:12px;text-align:center;font-size:14px;color:var(--text-2)}
.card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);transition:transform .3s ease,box-shadow .3s ease}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow-hover)}

/* ===== 作品预览 ===== */
.works-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin-top:44px}
.work-card{border-radius:var(--radius);overflow:hidden;border:1px solid var(--border);background:var(--card);transition:transform .3s ease,box-shadow .3s ease}
.work-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-hover)}
.work-card img{width:100%;height:auto}

/* ===== 产品介绍 ===== */
.intro-main{max-width:860px;margin:36px auto 0;font-size:15.5px;color:var(--text-2);line-height:2}
.intro-main p + p{margin-top:14px}
.intro-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-top:40px}
.intro-card{padding:26px 24px;display:flex;gap:16px;align-items:flex-start}
.i-icon{
  flex-shrink:0;width:46px;height:46px;border-radius:12px;
  background:var(--primary-soft);color:var(--primary);
  display:flex;align-items:center;justify-content:center;
}
.intro-card h3{font-size:16px;font-weight:700}
.intro-card p{margin-top:6px;font-size:13.5px;color:var(--text-2);line-height:1.7}

/* ===== 核心功能 ===== */
.feat-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-top:44px}
.feat-card{padding:30px 26px;text-align:center}
.feat-icon{
  width:56px;height:56px;margin:0 auto;border-radius:16px;
  background:var(--primary-soft);color:var(--primary);
  display:flex;align-items:center;justify-content:center;
}
.feat-card h3{margin-top:18px;font-size:17px;font-weight:700}
.feat-card p{margin-top:8px;font-size:14px;color:var(--text-2);line-height:1.7}

/* ===== 优势对比 ===== */
.cmp-wrap{margin-top:44px;overflow:hidden}
.cmp-table{width:100%;border-collapse:collapse;font-size:15px}
.cmp-table th,.cmp-table td{padding:16px 18px;text-align:center;border-bottom:1px solid var(--border)}
.cmp-table th{background:var(--bg);font-size:15px;font-weight:700}
.cmp-table th:first-child,.cmp-table td:first-child{text-align:left;color:var(--text-2);font-weight:500;width:180px}
.cmp-table .col-best{background:var(--primary-soft);color:var(--text);font-weight:700}
.cmp-table tbody tr:last-child td{border-bottom:none}
.cmp-ico{display:inline-flex;vertical-align:-3px;margin-right:6px}
.cmp-ok{color:var(--primary)}
.cmp-no{color:#B9BDC7}

/* ===== 平台数据 ===== */
.data-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin-top:44px}
.data-card{padding:34px 20px;text-align:center}
.data-card .num{font-size:38px;font-weight:800;color:var(--primary);line-height:1.1}
.data-card .num span{font-size:20px;font-weight:700;margin-left:2px}
.data-card .lab{margin-top:10px;font-size:14px;color:var(--text-2)}

/* ===== 用户评价 ===== */
.rev-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-top:44px}
.rev-card{padding:24px}
.rev-head{display:flex;align-items:center;gap:12px}
.avatar{
  width:44px;height:44px;border-radius:50%;flex-shrink:0;
  background:var(--primary-soft);color:var(--primary);
  font-size:17px;font-weight:700;
  display:flex;align-items:center;justify-content:center;
}
.rev-user{display:flex;flex-direction:column;gap:2px}
.rev-user .name{font-size:15px;font-weight:700}
.stars{color:#F5A623;font-size:13px;letter-spacing:2px}
.rev-text{margin-top:14px;font-size:14px;color:var(--text-2);line-height:1.8}

/* ===== 版本更新 ===== */
.update-card{max-width:760px;margin:44px auto 0;padding:34px 36px}
.up-head{display:flex;align-items:center;gap:16px;flex-wrap:wrap}
.ver-badge{
  display:inline-block;padding:6px 16px;border-radius:999px;
  background:var(--primary);color:#fff;font-size:15px;font-weight:700;
}
.up-date{font-size:14px;color:var(--text-2)}
.up-list{margin-top:22px;list-style:none}
.up-list li{position:relative;padding:9px 0 9px 26px;font-size:14.5px;line-height:1.7}
.up-list li::before{
  content:"";position:absolute;left:4px;top:50%;transform:translateY(-50%);
  width:8px;height:8px;border-radius:50%;background:var(--primary);
}

/* ===== FAQ ===== */
.faq-list{max-width:760px;margin:44px auto 0}
.faq-item{
  border:1px solid var(--border);border-radius:14px;background:var(--card);
  margin-bottom:14px;overflow:hidden;transition:box-shadow .3s ease,border-color .3s ease;
}
.faq-item.open{box-shadow:var(--shadow-sm);border-color:#F3D3D3}
.faq-q{
  width:100%;display:flex;align-items:center;justify-content:space-between;gap:14px;
  padding:18px 22px;font-size:15.5px;font-weight:600;color:var(--text);text-align:left;
  transition:color .2s ease;
}
.faq-q:hover{color:var(--primary)}
.faq-arrow{flex-shrink:0;color:var(--text-2);transition:transform .3s ease}
.faq-item.open .faq-arrow{transform:rotate(180deg);color:var(--primary)}
.faq-a{max-height:0;overflow:hidden;transition:max-height .32s ease}
.faq-a p{padding:0 22px 20px;font-size:14px;color:var(--text-2);line-height:1.8}

/* ===== 下载区域 ===== */
.download{
  background:linear-gradient(135deg,var(--deep) 0%,var(--deep-2) 100%);
  padding:88px 0;text-align:center;position:relative;overflow:hidden;
}
.download::before{
  content:"";position:absolute;top:-160px;right:-120px;
  width:420px;height:420px;border-radius:50%;
  background:radial-gradient(circle,rgba(232,69,69,.28),transparent 70%);
}
.dl-in{position:relative}
.download h1{color:#fff;font-size:34px;font-weight:800;letter-spacing:.5px}
.download h1 .ver{
  display:inline-block;margin-left:10px;padding:4px 12px;border-radius:999px;
  background:rgba(255,255,255,.14);color:#fff;font-size:16px;font-weight:700;vertical-align:6px;
}
.dl-meta{margin-top:16px;font-size:13px;color:rgba(255,255,255,.72);letter-spacing:.3px;white-space:nowrap}
.dl-meta .sep{margin:0 10px;opacity:.5}
.dl-btns{display:flex;justify-content:center;gap:16px;margin-top:30px;flex-wrap:wrap}
.download .btn-ghost{background:transparent;color:#fff;border:1.5px solid rgba(255,255,255,.7)}
.download .btn-ghost:hover{background:#fff;color:var(--deep);box-shadow:none}
.dl-tip{margin-top:26px;font-size:14px;color:rgba(255,255,255,.82)}

/* ===== 页脚 ===== */
.footer{background:var(--deep);padding:30px 0;text-align:center}
.footer p{font-size:13.5px;color:#9BA0AC}
.footer a{color:#fff;transition:color .2s ease}
.footer a:hover{color:var(--primary)}

/* ===== 返回顶部 ===== */
.back-top{
  position:fixed;right:26px;bottom:26px;z-index:99;
  width:46px;height:46px;border-radius:50%;
  background:var(--primary);color:#fff;
  display:flex;align-items:center;justify-content:center;
  box-shadow:0 8px 20px rgba(232,69,69,.35);
  opacity:0;visibility:hidden;transform:translateY(12px);
  transition:opacity .3s ease,transform .3s ease,visibility .3s ease;
}
.back-top.show{opacity:1;visibility:visible;transform:translateY(0)}
.back-top:hover{background:var(--primary-dark)}

/* ===== 平板适配 ===== */
@media (max-width:1024px){
  .works-grid{grid-template-columns:repeat(2,1fr)}
  .feat-grid{grid-template-columns:repeat(2,1fr)}
  .rev-grid{grid-template-columns:repeat(2,1fr)}
  .data-grid{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:960px){
  .nav{display:none}
  .header-in{justify-content:space-between}
}

/* ===== 手机适配 ===== */
@media (max-width:768px){
  section{scroll-margin-top:64px}
  .header-in{height:56px}
  .logo{font-size:18px}
  .hero{padding:112px 0 56px}
  .hero-in{grid-template-columns:1fr;gap:28px}
  .hero h1{font-size:28px}
  .hero h1 .ver{font-size:15px;vertical-align:4px}
  .hero-desc{font-size:15px}
  .hero-btns{flex-direction:column}
  .hero-btns .btn{width:100%}
  .hero-img{justify-content:center}
  .section{padding:56px 0}
  .sec-title{font-size:24px}
  .intro-cards{grid-template-columns:1fr}
  .cmp-table th,.cmp-table td{padding:12px 10px;font-size:13px}
  .cmp-table th:first-child,.cmp-table td:first-child{width:92px;font-size:12.5px}
  .cmp-ico{vertical-align:-2px;margin-right:4px}
  .update-card{padding:26px 20px}
  .download{padding:64px 0}
  .download h1{font-size:26px}
  .download h1 .ver{font-size:14px;vertical-align:4px}
  .dl-meta{font-size:12px}
  .dl-btns{flex-direction:column}
  .dl-btns .btn{width:100%}
  .dl-tip{font-size:13px}
  .back-top{right:16px;bottom:16px;width:42px;height:42px}
}
@media (max-width:600px){
  .works-grid{grid-template-columns:1fr}
  .feat-grid{grid-template-columns:1fr}
  .rev-grid{grid-template-columns:1fr}
}