/* ===== reset & tokens ===== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --bg:#0b1020;
  --bg-2:#111a33;
  --surface:#151f3a;
  --surface-2:#1b2748;
  --line:rgba(255,255,255,.09);
  --txt:#e8ecf6;
  --txt-dim:#9aa6c2;
  --accent:#4da3ff;
  --accent-2:#7c5cff;
  --ok:#39d98a;
  --radius:14px;
  --max:1140px;
  --font:"Segoe UI",-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
}
html{scroll-behavior:smooth}
body{
  font-family:var(--font);
  background:var(--bg);
  color:var(--txt);
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
ul{list-style:none}
.container{width:100%;max-width:var(--max);margin:0 auto;padding:0 22px}
.en{color:var(--txt-dim);font-size:.92em}

/* ===== nav ===== */
header{
  position:fixed;top:0;left:0;right:0;z-index:100;
  background:rgba(11,16,32,.72);
  backdrop-filter:blur(14px);
  border-bottom:1px solid transparent;
  transition:.3s;
}
header.scrolled{background:rgba(11,16,32,.94);border-bottom-color:var(--line)}
.nav{
  max-width:var(--max);margin:0 auto;padding:0 22px;
  height:66px;display:flex;align-items:center;justify-content:space-between;
}
.logo{font-weight:800;letter-spacing:2px;font-size:1.05rem}
.logo .dot{color:var(--accent)}
.nav-links{display:flex;gap:26px}
.nav-links a{
  font-size:.93rem;color:var(--txt-dim);position:relative;padding:4px 0;transition:.25s;
}
.nav-links a::after{
  content:"";position:absolute;left:0;bottom:0;width:0;height:2px;
  background:linear-gradient(90deg,var(--accent),var(--accent-2));transition:.25s;
}
.nav-links a:hover{color:var(--txt)}
.nav-links a:hover::after{width:100%}
.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer;padding:6px}
.nav-toggle span{width:24px;height:2px;background:var(--txt);border-radius:2px;transition:.3s}

/* ===== hero ===== */
.hero{position:relative;padding:150px 0 80px;overflow:hidden}
.hero-bg{
  position:absolute;inset:0;z-index:-1;
  background:
    radial-gradient(900px 460px at 12% 8%,rgba(77,163,255,.20),transparent 60%),
    radial-gradient(800px 420px at 88% 22%,rgba(124,92,255,.18),transparent 60%),
    linear-gradient(180deg,var(--bg),var(--bg-2));
}
.hero-bg::after{
  content:"";position:absolute;inset:0;
  background-image:linear-gradient(var(--line) 1px,transparent 1px),
                   linear-gradient(90deg,var(--line) 1px,transparent 1px);
  background-size:52px 52px;
  mask-image:radial-gradient(ellipse 70% 55% at 50% 30%,#000,transparent);
  -webkit-mask-image:radial-gradient(ellipse 70% 55% at 50% 30%,#000,transparent);
  opacity:.55;
}
.hero-inner{text-align:center;padding-bottom:64px}
.hero-eyebrow{
  font-size:.78rem;letter-spacing:4px;color:var(--accent);font-weight:600;margin-bottom:16px;
}
.hero-title{
  font-size:clamp(2.7rem,8vw,4.6rem);font-weight:800;line-height:1.1;letter-spacing:4px;
  background:linear-gradient(120deg,#fff 20%,var(--accent) 60%,var(--accent-2));
  -webkit-background-clip:text;background-clip:text;color:transparent;
  margin-bottom:14px;
}
.hero-sub{font-size:clamp(1rem,2.4vw,1.2rem);color:var(--txt);font-weight:500;margin-bottom:22px}
.hero-desc{max-width:720px;margin:0 auto 34px;color:var(--txt-dim);font-size:.96rem}
.hero-actions{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}
.btn{
  display:inline-block;padding:12px 30px;border-radius:999px;font-size:.94rem;font-weight:600;
  transition:.25s;border:1px solid transparent;
}
.btn-primary{background:linear-gradient(120deg,var(--accent),var(--accent-2));color:#fff;box-shadow:0 8px 26px rgba(77,163,255,.28)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 12px 32px rgba(77,163,255,.4)}
.btn-ghost{border-color:var(--line);color:var(--txt)}
.btn-ghost:hover{border-color:var(--accent);color:var(--accent);transform:translateY(-2px)}

/* ===== cards ===== */
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(272px,1fr));gap:20px}
.card{
  background:linear-gradient(160deg,var(--surface),var(--surface-2));
  border:1px solid var(--line);border-radius:var(--radius);
  padding:30px 26px;transition:.3s;position:relative;overflow:hidden;
}
.card::before{
  content:"";position:absolute;top:0;left:0;right:0;height:3px;
  background:linear-gradient(90deg,var(--accent),var(--accent-2));
  transform:scaleX(0);transform-origin:left;transition:.35s;
}
.card:hover{transform:translateY(-6px);border-color:rgba(77,163,255,.4);box-shadow:0 16px 40px rgba(0,0,0,.4)}
.card:hover::before{transform:scaleX(1)}
.card-icon{font-size:2rem;margin-bottom:12px}
.card h3{font-size:1.1rem;margin-bottom:10px}
.card p{color:var(--txt-dim);font-size:.92rem}

/* ===== sections ===== */
.section{padding:92px 0}
.section-alt{background:var(--bg-2)}
.section-title{
  font-size:clamp(1.6rem,4vw,2.2rem);font-weight:700;margin-bottom:14px;text-align:center;
}
.section-title .en-title{
  display:block;font-size:.8rem;letter-spacing:3px;color:var(--accent);
  font-weight:600;margin-top:6px;text-transform:uppercase;
}
.section-lead{
  max-width:800px;margin:0 auto 42px;text-align:center;color:var(--txt-dim);font-size:.96rem;
}

/* ===== about ===== */
.about-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:22px;margin-bottom:48px}
.about-block{
  background:var(--surface);border:1px solid var(--line);
  border-radius:var(--radius);padding:28px 26px;
}
.about-block h3{font-size:1.05rem;margin-bottom:16px;color:var(--accent)}
.ticks li{position:relative;padding-left:24px;margin-bottom:10px;color:var(--txt-dim);font-size:.92rem}
.ticks li::before{
  content:"▸";position:absolute;left:0;top:0;color:var(--ok);font-weight:700;
}
.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:16px}
.stat{
  text-align:center;padding:24px 12px;border:1px solid var(--line);border-radius:var(--radius);
  background:linear-gradient(160deg,var(--surface),transparent);
}
.stat-num{
  display:block;font-size:1.9rem;font-weight:800;
  background:linear-gradient(120deg,var(--accent),var(--accent-2));
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
.stat-label{font-size:.85rem;color:var(--txt-dim)}

/* ===== skills ===== */
.skill-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:20px}
.skill-col{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:26px 24px;
  transition:.3s;
}
.skill-col:hover{border-color:rgba(124,92,255,.4);transform:translateY(-4px)}
.skill-col h3{font-size:1rem;margin-bottom:16px;display:flex;align-items:center;gap:9px}
.sk-ico{font-size:1.15rem}
.tags{display:flex;flex-wrap:wrap;gap:8px}
.tags span{
  font-size:.79rem;padding:5px 12px;border-radius:999px;
  background:rgba(77,163,255,.1);border:1px solid rgba(77,163,255,.24);color:#cfe0ff;
}

/* ===== services ===== */
.svc-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(310px,1fr));gap:20px}
.svc{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:30px 26px;position:relative;transition:.3s;overflow:hidden;
}
.svc-num{
  position:absolute;top:14px;right:20px;font-size:2.6rem;font-weight:800;
  color:rgba(255,255,255,.05);line-height:1;
}
.svc h3{font-size:1.06rem;margin-bottom:11px;color:var(--txt)}
.svc p{color:var(--txt-dim);font-size:.92rem}
.svc:hover{transform:translateY(-6px);border-color:rgba(77,163,255,.4);box-shadow:0 16px 40px rgba(0,0,0,.4)}

/* ===== env ===== */
.env-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(290px,1fr));gap:20px}
.env-card{
  background:linear-gradient(160deg,var(--surface),var(--surface-2));
  border:1px solid var(--line);border-left:3px solid var(--accent);
  border-radius:10px;padding:24px 24px;
}
.env-card h4{font-size:1rem;margin-bottom:14px}
.env-card li{
  padding-left:18px;position:relative;color:var(--txt-dim);font-size:.9rem;margin-bottom:8px;
}
.env-card li::before{content:"·";position:absolute;left:4px;color:var(--accent);font-weight:800;font-size:1.3em;line-height:1}

/* ===== contact ===== */
.contact-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:18px;margin-bottom:26px}
.contact-item{
  display:flex;flex-direction:column;align-items:center;gap:6px;text-align:center;
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:28px 20px;transition:.3s;
}
.contact-item:hover{border-color:var(--accent);transform:translateY(-4px)}
.ci-ico{font-size:1.6rem}
.ci-label{font-size:.8rem;color:var(--txt-dim);letter-spacing:1px}
.ci-val{font-size:.95rem;font-weight:600;word-break:break-all}
.contact-note{text-align:center;color:var(--txt-dim);font-size:.9rem}

/* ===== footer ===== */
.footer{border-top:1px solid var(--line);padding:26px 0;background:var(--bg-2)}
.footer-inner{
  display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;
  font-size:.85rem;color:var(--txt-dim);
}

/* ===== to top ===== */
.to-top{
  position:fixed;right:22px;bottom:22px;width:44px;height:44px;border-radius:50%;
  display:grid;place-items:center;font-size:1.2rem;
  background:linear-gradient(120deg,var(--accent),var(--accent-2));color:#fff;
  box-shadow:0 8px 24px rgba(77,163,255,.35);
  opacity:0;pointer-events:none;transition:.3s;z-index:90;
}
.to-top.show{opacity:1;pointer-events:auto}
.to-top:hover{transform:translateY(-3px)}

/* ===== reveal animation ===== */
.reveal{opacity:0;transform:translateY(26px);transition:opacity .7s ease,transform .7s ease}
.reveal.in{opacity:1;transform:none}

/* ===== responsive ===== */
@media(max-width:820px){
  .nav-toggle{display:flex}
  .nav-links{
    position:absolute;top:66px;left:0;right:0;
    flex-direction:column;gap:0;
    background:rgba(11,16,32,.98);border-bottom:1px solid var(--line);
    max-height:0;overflow:hidden;transition:max-height .35s ease;
  }
  .nav-links.open{max-height:340px}
  .nav-links li{border-top:1px solid var(--line)}
  .nav-links a{display:block;padding:14px 22px}
  .nav-links a::after{display:none}
  .hero{padding-top:120px}
  .section{padding:66px 0}
  .footer-inner{justify-content:center;text-align:center}
}
@media(prefers-reduced-motion:reduce){
  *{animation:none!important;transition:none!important}
  .reveal{opacity:1;transform:none}
}