/* ===== Reset & Base ===== */
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  line-height:1.65;color:#1e293b;background:#fff;
}
a{text-decoration:none;color:inherit}
img{max-width:100%;height:auto;display:block}

.wrap{max-width:1080px;margin:0 auto;padding:0 24px}

/* ===== Header ===== */
.header{
  position:fixed;top:0;left:0;right:0;z-index:100;
  background:rgba(255,255,255,.97);
  backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);
  border-bottom:1px solid #e5e7eb;
}
.nav{display:flex;align-items:center;justify-content:space-between;height:56px}
.logo{display:flex;align-items:center;gap:10px}
.logo-icon{width:30px;height:30px;border-radius:7px}
.logo-name{font-size:16px;font-weight:700;color:#0f172a}
.nav-right{display:flex;gap:28px}
.nav-a{font-size:14px;color:#64748b;padding:4px 0;border-bottom:2px solid transparent;transition:color .2s,border-color .2s}
.nav-a:hover,.nav-active{color:#2563eb;border-bottom-color:#2563eb}

/* ===== Buttons ===== */
.btn{display:inline-block;font-weight:600;border-radius:8px;text-align:center;transition:transform .15s,box-shadow .15s,background .15s}
.btn-hero-primary{padding:14px 36px;font-size:15px;background:#fff;color:#1d4ed8}
.btn-hero-primary:hover{transform:translateY(-2px);box-shadow:0 8px 20px rgba(0,0,0,.15)}
.btn-hero-outline{padding:14px 28px;font-size:14px;background:rgba(255,255,255,.1);color:#fff;border:1px solid rgba(255,255,255,.35)}
.btn-hero-outline:hover{background:rgba(255,255,255,.2)}
.btn-dl{display:block;width:100%;padding:13px 0;font-size:15px;background:#2563eb;color:#fff;margin-bottom:6px}
.btn-dl:hover{background:#1d4ed8;transform:translateY(-1px)}

/* ===== Hero (index) ===== */
.hero{
  margin-top:56px;padding:76px 0 68px;
  background:linear-gradient(135deg,#0f172a 0%,#1e3a5f 40%,#2563eb 100%);
  color:#fff;
}
.hero h1{font-size:46px;font-weight:800;line-height:1.15;margin-bottom:18px}
.hero-sub{font-size:17px;line-height:1.8;color:rgba(255,255,255,.82);max-width:620px;margin-bottom:36px}
.hero-btns{display:flex;flex-wrap:wrap;gap:10px;margin-bottom:10px}
.hero-hint{font-size:12px;color:rgba(255,255,255,.45);margin-top:6px}

/* ===== Download Hero ===== */
.dl-hero{
  margin-top:56px;padding:52px 0 40px;text-align:center;
  background:linear-gradient(135deg,#0f172a 0%,#1e3a5f 40%,#2563eb 100%);
  color:#fff;
}
.dl-hero h1{font-size:34px;font-weight:800;margin-bottom:10px}
.dl-hero-sub{font-size:15px;color:rgba(255,255,255,.72)}

/* ===== Sections ===== */
.section{padding:64px 0}
.sec-reviews{background:#f8fafc}
.sec-knowledge{background:#fff}
.sec-platforms{background:#f8fafc}
.sec-channels{background:#fff}
.sec-heading{font-size:26px;font-weight:700;color:#0f172a;text-align:center;margin-bottom:42px}

/* ===== Grid ===== */
.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
.grid-narrow{max-width:680px;margin-left:auto;margin-right:auto}

/* ===== Review Cards ===== */
.review-card{background:#fff;padding:26px;border-radius:12px;border:1px solid #e2e8f0}
.review-stars{color:#f59e0b;font-size:15px;letter-spacing:2px;margin-bottom:12px}
.review-text{font-size:14px;line-height:1.8;color:#475569;margin-bottom:18px}
.review-user{display:flex;align-items:center;gap:12px}
.review-avatar{width:40px;height:40px;border-radius:50%;object-fit:cover}
.review-name{font-size:14px;font-weight:600;color:#1e293b}
.review-from{font-size:12px;color:#94a3b8}

/* ===== Knowledge Cards ===== */
.kcard{
  padding:26px;background:#f8fafc;border-radius:12px;border:1px solid #e2e8f0;
  transition:border-color .2s,box-shadow .2s;
}
.kcard:hover{border-color:#93c5fd;box-shadow:0 4px 14px rgba(37,99,235,.07)}
.kcard h3{font-size:15px;font-weight:700;color:#1e293b;margin-bottom:8px}
.kcard p{font-size:13.5px;line-height:1.8;color:#64748b}

/* ===== Platform Cards ===== */
.pl-card{
  background:#fff;padding:30px 24px;border-radius:14px;border:1px solid #e2e8f0;
  text-align:center;transition:border-color .2s,box-shadow .2s;
}
.pl-card:hover{border-color:#93c5fd;box-shadow:0 6px 20px rgba(37,99,235,.08)}
.pl-icon{margin-bottom:14px}
.pl-icon svg{display:inline-block}
.pl-name{font-size:19px;font-weight:700;color:#1e293b;margin-bottom:6px}
.pl-ver{font-size:12.5px;color:#94a3b8;margin-bottom:4px}
.pl-req{font-size:13px;color:#64748b;margin-bottom:18px;line-height:1.5}
.dl-hint{display:block;text-align:center;font-size:11.5px;color:#94a3b8;margin-bottom:12px}
.pl-variants{font-size:13px;color:#64748b;margin-top:4px}
.vl{color:#2563eb;transition:color .15s}
.vl:hover{color:#1d4ed8;text-decoration:underline}
.vl-sep{margin:0 5px;color:#cbd5e1}

/* ===== Channel Cards ===== */
.ch-card{padding:26px;border-radius:12px;border:1px solid #e2e8f0;background:#f8fafc}
.ch-card.ch-active{border-color:#2563eb;background:#eff6ff}
.ch-card h3{font-size:16px;font-weight:700;color:#1e293b;margin-bottom:8px}
.ch-card p{font-size:13.5px;line-height:1.75;color:#64748b}

/* ===== Footer ===== */
.footer{padding:44px 0 28px;background:#0f172a;color:#94a3b8}
.footer-disclaimer{text-align:center;margin-bottom:20px}
.footer-disclaimer p{font-size:13px;line-height:1.9}
.footer-copy{text-align:center;font-size:12px;color:#475569;padding-top:18px;border-top:1px solid rgba(255,255,255,.06)}

/* ===== Responsive ===== */
@media(max-width:900px){
  .grid-3{grid-template-columns:repeat(2,1fr)}
  .hero h1{font-size:34px}
  .hero-sub{font-size:15px}
}
@media(max-width:600px){
  .wrap{padding:0 16px}
  .hero{padding:56px 0 48px}
  .hero h1{font-size:28px}
  .hero-btns{flex-direction:column}
  .btn-hero-primary,.btn-hero-outline{width:100%;text-align:center}
  .grid-3,.grid-2{grid-template-columns:1fr}
  .grid-narrow{max-width:100%}
  .sec-heading{font-size:22px}
  .dl-hero h1{font-size:26px}
  .section{padding:48px 0}
}