:root {
  --primary: #D4213D;
  --primary-dark: #A0182D;
  --primary-light: #FF5C72;
  --primary-ghost: #FFF0F2;
  --bg: #FDFDFD;
  --bg-card: #FFFFFF;
  --bg-gray: #F5F6F8;
  --bg-dark: #0A0B0F;
  --text: #111111;
  --text-dim: #6A6E76;
  --text-muted: #9CA3AF;
  --border: #E5E7EB;
  --border-light: #F0F0F3;
  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 24px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,.03);
  --shadow: 0 2px 16px rgba(0,0,0,.04);
  --shadow-md: 0 8px 32px rgba(0,0,0,.06);
  --max-w: 960px;
}

*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  color:var(--text);background:var(--bg);line-height:1.72;letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}
button{font-family:inherit;cursor:pointer;border:none;background:none;color:inherit;transition:transform .15s}
button:active{transform:scale(.97)}
ul{list-style:none}
img{display:block;max-width:100%}
.container{max-width:var(--max-w);margin:0 auto;padding:0 32px}

/* Animations */
@keyframes fadeInUp{from{opacity:0;transform:translateY(24px)}to{opacity:1;transform:translateY(0)}}
@keyframes heroIn{from{opacity:0;transform:translateY(32px)}to{opacity:1;transform:translateY(0)}}

.reveal{opacity:0;transition:opacity .7s ease,transform .7s ease}
.reveal.visible{opacity:1;transform:translateY(0)!important}
.reveal[data-stagger="1"]{transition-delay:.06s}
.reveal[data-stagger="2"]{transition-delay:.12s}
.reveal[data-stagger="3"]{transition-delay:.18s}
.reveal[data-stagger="4"]{transition-delay:.24s}

/* Hero entrance on load */
.hero .badge,.hero h1,.hero p,.hero-actions .btn,
.page-hero .ph-logo,.page-hero h1,.page-hero p,
.dl-hero-text h1,.dl-hero-text p{animation:heroIn .8s ease backwards}
.hero .badge,.page-hero .ph-logo,.dl-hero-text h1{animation-delay:.05s}
.hero h1,.page-hero h1,.dl-hero-text p{animation-delay:.15s}
.hero p,.page-hero p,.dl-card{animation-delay:.25s}
.hero-actions .btn:nth-child(1){animation-delay:.32s}
.hero-actions .btn:nth-child(2){animation-delay:.38s}

/* Nav */
.nav{position:fixed;top:0;left:0;right:0;z-index:100;background:rgba(253,253,253,.86);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);transition:box-shadow .3s}
.nav.scrolled{box-shadow:0 0 0 1px rgba(0,0,0,.04)}
.nav-inner{max-width:var(--max-w);margin:0 auto;padding:0 32px;display:flex;align-items:center;justify-content:space-between;height:64px}
.nav-logo{display:flex;align-items:center;gap:10px;font-size:18px;font-weight:750;color:var(--text);letter-spacing:-.02em}
.nav-logo .logo-img{width:34px;height:34px;border-radius:9px;object-fit:cover}
.nav-links{display:flex;align-items:center;gap:36px}
.nav-links a{font-size:13.5px;color:var(--text-dim);font-weight:500;position:relative;transition:color .2s}
.nav-links a::after{content:"";position:absolute;bottom:-4px;left:0;width:0;height:2px;border-radius:1px;background:var(--primary);transition:width .25s ease}
.nav-links a:hover::after,.nav-links a.active::after{width:100%}
.nav-links a:hover,.nav-links a.active{color:var(--primary)}
.nav-cta{background:var(--primary);color:#fff;padding:8px 20px;border-radius:18px;font-size:13px;font-weight:600;transition:background .2s}
.nav-cta:hover{background:var(--primary-dark)}
.nav-cta::after{display:none}
.menu-toggle{display:none;padding:4px}

/* Buttons */
.btn{display:inline-flex;align-items:center;gap:8px;padding:14px 34px;border-radius:28px;font-size:15px;font-weight:600;transition:all .2s}
.btn-primary{background:var(--primary);color:#fff}
.btn-primary:hover{background:var(--primary-dark)}
.btn-outline{color:var(--primary);border:2px solid rgba(212,33,61,.25)}
.btn-outline:hover{border-color:var(--primary);background:var(--primary);color:#fff}
.btn-lg{padding:16px 40px;font-size:16px}
.btn-light{background:var(--bg-card);color:var(--primary);box-shadow:var(--shadow-sm)}
.btn-light:hover{box-shadow:var(--shadow)}
.btn-ghost{color:#fff;border:1px solid rgba(255,255,255,.2)}
.btn-ghost:hover{background:rgba(255,255,255,.1)}

/* Badge */
.badge{display:inline-flex;align-items:center;gap:6px;background:var(--primary-ghost);color:var(--primary);padding:5px 14px;border-radius:16px;font-size:12px;font-weight:600}

/* Hero (Index) */
.hero{padding:180px 0 120px;text-align:center}
.hero .badge{margin-bottom:28px}
.hero h1{font-size:56px;font-weight:880;letter-spacing:-.03em;line-height:1.1;margin-bottom:24px;max-width:600px;margin-left:auto;margin-right:auto}
.hero h1 em{font-style:normal;color:var(--primary)}
.hero p{font-size:17px;color:var(--text-dim);max-width:500px;margin:0 auto 40px;line-height:1.85}
.hero-actions{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}

/* Page Hero */
.page-hero{padding:160px 0 80px;text-align:center;background:linear-gradient(180deg,var(--primary-ghost),transparent 100%)}
.page-hero h1{font-size:42px;font-weight:850;letter-spacing:-.025em;margin-bottom:12px}
.page-hero p{font-size:16px;color:var(--text-dim)}
.page-hero .ph-logo{width:64px;height:64px;border-radius:18px;margin:0 auto 20px}

/* Section */
.section{padding:120px 0}
.section-gray{background:var(--bg-gray)}
.section-dark{background:var(--bg-dark);color:#fff}
.section-header{margin-bottom:72px;text-align:center}
.section-header h2{font-size:36px;font-weight:850;letter-spacing:-.02em;margin-bottom:12px}
.section-header p{font-size:16px;color:var(--text-dim)}
.section-divider{width:36px;height:3px;border-radius:2px;background:var(--primary);margin:16px auto 0;opacity:.3}

/* Cards */
.card-grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.card-grid-4{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.card-grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:24px}

.card{background:var(--bg-card);border-radius:var(--radius);padding:48px 40px;text-align:center;border:1px solid var(--border-light);transition:transform .3s ease,box-shadow .3s ease,border-color .3s ease}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow-md);border-color:transparent}
.card-icon{width:48px;height:48px;border-radius:12px;display:flex;align-items:center;justify-content:center;margin:0 auto 22px;color:var(--primary);background:var(--primary-ghost)}
.card h3{font-size:18px;font-weight:750;margin-bottom:10px;letter-spacing:-.01em}
.card p{font-size:14px;color:var(--text-dim);line-height:1.85}

/* Stats */
.stat-card{text-align:center;padding:48px 24px;background:var(--bg-card);border-radius:var(--radius);border:1px solid var(--border-light);transition:transform .3s ease,box-shadow .3s ease}
.stat-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-md)}
.stat-number{font-size:48px;font-weight:920;color:var(--primary);letter-spacing:-.04em;line-height:1;margin-bottom:10px}
.stat-label{font-size:13px;color:var(--text-muted);font-weight:500}

/* Feature Row */
.feat-row{max-width:640px;margin:0 auto;padding:56px 0}
.feat-row+.feat-row{border-top:1px solid var(--border-light)}
.feat-content h3{font-size:22px;font-weight:800;letter-spacing:-.015em;margin-bottom:18px;display:flex;align-items:center;gap:12px}
.feat-content h3>svg{flex-shrink:0;color:var(--primary)}
.feat-lead{font-size:15px;color:var(--text-dim);line-height:1.9;margin-bottom:22px}
.feat-list{margin-bottom:20px}
.feat-list li{display:flex;align-items:flex-start;gap:10px;margin-bottom:10px;font-size:14px;color:var(--text-dim);line-height:1.8}
.feat-list li>svg{flex-shrink:0;margin-top:3px;color:var(--primary)}
.feat-tags{display:flex;flex-wrap:wrap;gap:8px}
.feat-tags span{background:var(--primary-ghost);color:var(--primary);padding:5px 14px;border-radius:16px;font-size:12px;font-weight:550}

.section-dark .feat-row+.feat-row{border-top-color:rgba(255,255,255,.06)}
.section-dark .feat-content h3{color:#fff}
.section-dark .feat-lead{color:rgba(255,255,255,.45)}
.section-dark .feat-list li{color:rgba(255,255,255,.35)}
.section-dark .feat-list li>svg{color:var(--primary-light)}
.section-dark .feat-tags span{background:rgba(212,33,61,.15);color:var(--primary-light)}
.section-dark .card{background:rgba(255,255,255,.02);border-color:rgba(255,255,255,.04)}
.section-dark .card h3{color:#fff}
.section-dark .card p{color:rgba(255,255,255,.35)}
.section-dark .card:hover{border-color:rgba(255,255,255,.1);box-shadow:none}

/* CTA */
.cta{padding:100px 0;text-align:center;background:var(--primary);color:#fff}
.cta h2{font-size:36px;font-weight:850;letter-spacing:-.02em;margin-bottom:12px}
.cta p{font-size:16px;opacity:.7;margin-bottom:32px}
.cta .btn-light{font-weight:650}

/* Footer */
.footer{padding:72px 0 32px;background:var(--bg-dark);color:rgba(255,255,255,.3);font-size:13px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:56px;margin-bottom:52px}
.footer-brand .logo-img{width:34px;height:34px;border-radius:9px;object-fit:cover;margin-bottom:16px}
.footer-brand p{color:rgba(255,255,255,.4);margin-bottom:4px}
.footer h4{color:rgba(255,255,255,.7);font-size:13px;font-weight:650;margin-bottom:16px}
.footer ul li{margin-bottom:10px}
.footer ul a{color:rgba(255,255,255,.25);transition:color .2s}
.footer ul a:hover{color:rgba(255,255,255,.5)}
.footer-bottom{border-top:1px solid rgba(255,255,255,.05);padding-top:24px;display:flex;justify-content:space-between;color:rgba(255,255,255,.15);font-size:12px}

/* Download */
.dl-page{padding:180px 0 120px;text-align:center}
.dl-hero-text{margin-bottom:56px}
.dl-hero-text h1{font-size:42px;font-weight:850;letter-spacing:-.025em;margin-bottom:10px}
.dl-hero-text p{font-size:16px;color:var(--text-dim)}
.dl-card{max-width:380px;margin:0 auto;background:var(--bg-card);border-radius:var(--radius-lg);padding:56px 48px;border:1px solid var(--border-light);text-align:center;transition:transform .3s ease,box-shadow .3s ease;animation:heroIn .8s .25s ease backwards}
.dl-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-md)}
.dl-icon{width:80px;height:80px;border-radius:20px;object-fit:cover;margin:0 auto 24px}
.dl-card h2{font-size:22px;font-weight:850;margin-bottom:6px;letter-spacing:-.01em}
.dl-ver{font-size:13px;color:var(--text-muted);margin-bottom:32px}
.dl-btn-main{display:flex;align-items:center;justify-content:center;gap:10px;width:100%;padding:17px;border-radius:28px;font-size:16px;font-weight:650;background:var(--primary);color:#fff;margin-bottom:30px;transition:background .2s}
.dl-btn-main:hover{background:var(--primary-dark)}
.dl-meta{text-align:left;border-top:1px solid var(--border-light);padding-top:24px}
.dl-meta p{font-size:13px;color:var(--text-dim);margin-bottom:8px;display:flex;align-items:center;gap:8px}
.dl-note{margin-top:28px;font-size:13px;color:var(--text-muted)}

/* About */
.about-founder{display:grid;grid-template-columns:200px 1fr;gap:52px;align-items:start;background:var(--bg-card);border-radius:var(--radius-lg);padding:52px;border:1px solid var(--border-light);transition:transform .3s ease,box-shadow .3s ease}
.about-founder:hover{transform:translateY(-4px);box-shadow:var(--shadow-md)}
.founder-side{text-align:center}
.founder-avatar{width:120px;height:120px;border-radius:50%;object-fit:cover;margin:0 auto 18px}
.founder-role{font-size:12.5px;color:var(--primary);font-weight:650;text-transform:uppercase;letter-spacing:.05em}
.founder-body h3{font-size:26px;font-weight:850;margin-bottom:6px;letter-spacing:-.015em}
.founder-body .sub-role{font-size:14px;color:var(--primary);font-weight:600;margin-bottom:20px}
.founder-body p{font-size:15px;color:var(--text-dim);line-height:1.95;margin-bottom:12px}

.server-card{display:flex;gap:18px;padding:32px 28px;background:var(--bg-card);border-radius:var(--radius);border:1px solid var(--border-light);transition:transform .3s ease,box-shadow .3s ease}
.server-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-md)}
.sc-icon{flex-shrink:0;width:44px;height:44px;border-radius:10px;background:var(--primary-ghost);display:flex;align-items:center;justify-content:center;color:var(--primary)}
.server-card h4{font-size:15px;font-weight:700;margin-bottom:4px}
.server-card p{font-size:13px;color:var(--text-dim);line-height:1.75}

.story-text{max-width:640px;margin:0 auto;text-align:center}
.story-text p{font-size:17px;color:var(--text-dim);line-height:2.1;margin-bottom:18px}

/* BTT */
.btt{position:fixed;bottom:28px;right:28px;z-index:90;width:40px;height:40px;border-radius:50%;background:var(--bg-card);color:var(--primary);border:1px solid var(--border-light);display:flex;align-items:center;justify-content:center;opacity:0;transform:translateY(10px);transition:all .3s;pointer-events:none;box-shadow:var(--shadow)}
.btt.show{opacity:1;transform:translateY(0);pointer-events:auto}
.btt:hover{background:var(--primary);color:#fff;border-color:var(--primary)}

/* Nav Overlay */
.nav-overlay{display:none;position:fixed;inset:0;background:rgba(0,0,0,.2);z-index:99;backdrop-filter:blur(2px)}

/* Responsive */
@media(max-width:1024px){
  .hero h1{font-size:44px}
}
@media(max-width:768px){
  .container{padding:0 20px}
  .nav-inner{padding:0 20px}
  .nav-links{display:none}
  .nav-links.open{display:flex;flex-direction:column;position:absolute;top:64px;left:0;right:0;background:var(--bg-card);padding:24px 20px;gap:20px;border-bottom:1px solid var(--border);box-shadow:var(--shadow-md);z-index:101}
  .nav-overlay.show{display:block}
  .menu-toggle{display:block}
  .footer-grid{grid-template-columns:1fr;gap:36px}
  .footer-bottom{flex-direction:column;gap:8px;text-align:center}
  .card-grid-3,.card-grid-4,.card-grid-2{grid-template-columns:1fr}
  .about-founder{grid-template-columns:1fr;gap:32px;padding:40px 32px}
  .hero{padding:140px 0 72px}
  .hero h1{font-size:36px}
  .page-hero{padding:140px 0 60px}
  .page-hero h1{font-size:32px}
  .section{padding:72px 0}
  .section-header{margin-bottom:52px}
  .section-header h2{font-size:26px}
  .cta h2{font-size:26px}
  .dl-card{padding:40px 32px}
  .dl-page{padding:140px 0 80px}
  .dl-hero-text h1{font-size:32px}
  .btt{bottom:20px;right:20px}
  .feat-row{padding:40px 0}
  .page-hero .ph-logo{width:52px;height:52px;border-radius:14px}
}
@media(max-width:480px){
  .hero h1{font-size:30px}
  .cta{padding:72px 0}
  .cta h2{font-size:22px}
  .section-header h2{font-size:24px}
  .feat-content h3{font-size:20px}
  .dl-hero-text h1{font-size:28px}
}