/* ============================================================
   三角洲辅助导航站 — 冷光雷达 HUD 设计系统
   palette: 深蓝黑底 / 冰晶青 / 发丝线 / 等宽编号
   ============================================================ */

:root{
  --bg:#060a0f;
  --bg-alt:#0a1118;
  --surface:#0e1720;
  --surface-2:#15202c;
  --line:#1b2936;
  --line-2:#2a3e4e;
  --text:#e6f1f8;
  --text-2:#9fb3c2;
  --text-3:#5f7486;
  --accent:#38e1d4;
  --accent-hi:#86f6ec;
  --accent-dim:rgba(56,225,212,.10);
  --accent-line:rgba(56,225,212,.38);
  --err:#ff5c5c;
  --sans:"Inter","Noto Sans SC",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --mono:"JetBrains Mono",Consolas,"Courier New",monospace;
  --radius:14px;
  --ease:cubic-bezier(.22,.9,.35,1);
}

*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:var(--sans);
  background:var(--bg);
  color:var(--text);
  line-height:1.6;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
a{text-decoration:none;color:inherit}
ul,ol{list-style:none}
button{font-family:inherit;cursor:pointer}
::selection{background:var(--accent);color:#060a0f}
::-webkit-scrollbar{width:9px}
::-webkit-scrollbar-track{background:var(--bg-alt)}
::-webkit-scrollbar-thumb{background:var(--line-2);border-radius:6px}
::-webkit-scrollbar-thumb:hover{background:var(--accent)}

.container{max-width:1200px;margin:0 auto;padding:0 24px}

/* 滚动显现 */
.reveal{opacity:0;transform:translateY(26px);transition:opacity .7s var(--ease),transform .7s var(--ease);transition-delay:var(--d,0ms)}
.reveal.in{opacity:1;transform:none}

/* ================= 导航 ================= */
.nav{
  position:sticky;top:0;z-index:100;
  background:rgba(6,10,15,.88);
  backdrop-filter:blur(14px);
  -webkit-backdrop-filter:blur(14px);
  border-bottom:1px solid var(--line);
}
.nav-inner{display:flex;align-items:center;gap:28px;height:72px}
.logo{display:flex;flex-direction:column;line-height:1.15;margin-right:auto}
.logo-mark{font-weight:800;letter-spacing:.08em;font-size:1.05rem;color:var(--text)}
.logo-mark::before{content:"// ";color:var(--accent);font-family:var(--mono);font-weight:600}
.logo-sub{font-family:var(--mono);font-size:.62rem;letter-spacing:.28em;color:var(--text-3);margin-top:2px}
.nav-links{display:flex;align-items:center;gap:6px}
.nav-link{
  position:relative;padding:8px 14px;font-size:.9rem;font-weight:500;color:var(--text-2);
  border-radius:8px;transition:color .18s,background .18s;
}
.nav-link::after{
  content:"";position:absolute;left:14px;right:14px;bottom:3px;height:2px;border-radius:2px;
  background:var(--accent);transform:scaleX(0);transform-origin:left;transition:transform .25s var(--ease);
}
.nav-link:hover{color:var(--text)}
.nav-link:hover::after,.nav-link.is-active::after{transform:scaleX(1)}
.nav-link.is-active{color:var(--accent-hi)}
.nav-cta{
  display:inline-flex;align-items:center;gap:8px;margin-left:10px;
  background:var(--accent);color:#060a0f;font-weight:700;font-size:.88rem;
  padding:10px 20px;border-radius:10px;transition:background .18s,transform .18s,box-shadow .18s;
}
.nav-cta:hover{background:var(--accent-hi);transform:translateY(-1px);box-shadow:0 8px 22px rgba(56,225,212,.26)}
.nav-cta i{font-size:1rem}
.nav-toggle{display:none;background:none;border:1px solid var(--line-2);color:var(--text);border-radius:9px;width:42px;height:42px;font-size:1.3rem;align-items:center;justify-content:center}

/* ================= 按钮 ================= */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:10px;
  border-radius:11px;padding:14px 26px;font-size:.95rem;font-weight:700;
  transition:transform .18s var(--ease),box-shadow .18s,border-color .18s,background .18s,color .18s;
}
.btn-primary{
  background:var(--accent);color:#060a0f;box-shadow:0 10px 26px rgba(56,225,212,.22);
}
.btn-primary:hover{background:var(--accent-hi);transform:translateY(-2px);box-shadow:0 14px 34px rgba(56,225,212,.32)}
.btn-ghost{
  border:1px solid var(--line-2);color:var(--text);
}
.btn-ghost:hover{border-color:var(--accent);color:var(--accent-hi);background:var(--accent-dim);transform:translateY(-2px)}
.btn i{font-size:1.05rem}

/* ================= Hero ================= */
.hero{position:relative;padding:86px 0 0;overflow:hidden}
.hero-bg-grid{
  position:absolute;inset:0;pointer-events:none;
  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 90% 80% at 50% 0%,#000 30%,transparent 78%);
  -webkit-mask-image:radial-gradient(ellipse 90% 80% at 50% 0%,#000 30%,transparent 78%);
  opacity:.5;
}
.hero::after{
  content:"";position:absolute;top:-220px;right:-160px;width:560px;height:560px;pointer-events:none;
  background:radial-gradient(circle,rgba(56,225,212,.12),transparent 65%);
}
.hero-grid{
  position:relative;display:grid;grid-template-columns:1.1fr .9fr;gap:64px;align-items:center;padding-bottom:90px;
}
.hero-copy{max-width:620px}
.hero-badge{
  display:inline-flex;align-items:center;gap:9px;
  font-family:var(--mono);font-size:.78rem;letter-spacing:.12em;color:var(--accent-hi);
  border:1px solid var(--accent-line);background:var(--accent-dim);
  padding:7px 16px;border-radius:999px;margin-bottom:26px;
}
.pulse-dot{width:7px;height:7px;border-radius:50%;background:var(--accent);box-shadow:0 0 0 0 rgba(56,225,212,.55);animation:pulse 2.2s infinite}
@keyframes pulse{
  0%{box-shadow:0 0 0 0 rgba(56,225,212,.5)}
  70%{box-shadow:0 0 0 9px rgba(56,225,212,0)}
  100%{box-shadow:0 0 0 0 rgba(56,225,212,0)}
}
.hero-title{font-size:clamp(2.6rem,6vw,4.3rem);font-weight:900;letter-spacing:-.03em;line-height:1.08;margin-bottom:22px}
.hero-line{display:block}
.hero-line-accent{
  background:linear-gradient(94deg,#8cf6ec 0%,#38e1d4 55%,#1796b8 100%);
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
.hero-desc{font-size:1.02rem;color:var(--text-2);max-width:540px;line-height:1.85;margin-bottom:32px}
.hero-actions{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin-bottom:26px}
.hero-note{display:flex;align-items:center;gap:10px;font-size:.82rem;color:var(--text-3);font-family:var(--mono)}
.hero-note i{color:var(--accent);font-size:1.05rem}

/* Hero 视觉框 */
.hero-visual{position:relative;justify-self:end;width:100%;max-width:520px}
.hero-frame{
  position:relative;border:1px solid var(--line-2);border-radius:var(--radius);
  background:var(--surface);padding:10px;overflow:hidden;
}
.hero-frame::before{
  content:"";position:absolute;inset:0;border-radius:var(--radius);
  background:linear-gradient(135deg,rgba(56,225,212,.12),transparent 40%);
  pointer-events:none;z-index:1;
}
.hero-frame img{position:relative;border-radius:8px;width:100%;aspect-ratio:4/3;object-fit:cover;filter:saturate(1.05) contrast(1.04)}
.frame-tick{position:absolute;width:18px;height:18px;border-color:var(--accent);border-style:solid;z-index:2}
.frame-tick.tl{top:18px;left:18px;border-width:2px 0 0 2px}
.frame-tick.tr{top:18px;right:18px;border-width:2px 2px 0 0}
.frame-tick.bl{bottom:18px;left:18px;border-width:0 0 2px 2px}
.frame-tick.br{bottom:18px;right:18px;border-width:0 2px 2px 0}
.frame-chip{
  position:absolute;top:20px;left:50%;transform:translateX(-50%);z-index:2;
  font-family:var(--mono);font-size:.64rem;letter-spacing:.2em;color:var(--accent-hi);
  background:rgba(6,10,15,.72);border:1px solid var(--accent-line);
  padding:5px 12px;border-radius:999px;backdrop-filter:blur(4px);
}
.frame-code{
  position:absolute;bottom:18px;right:18px;z-index:2;
  font-family:var(--mono);font-size:.64rem;letter-spacing:.18em;color:var(--text-3);
  background:rgba(6,10,15,.72);border:1px solid var(--line-2);padding:5px 10px;border-radius:6px;
}
.frame-scan{
  position:absolute;left:0;right:0;height:56px;z-index:1;pointer-events:none;
  background:linear-gradient(180deg,transparent,rgba(134,246,236,.08),transparent);
  animation:scan 4.5s linear infinite;
}
@keyframes scan{0%{top:-10%}100%{top:110%}}

/* ================= 通用分节 ================= */
.section{padding:104px 0}
.section-alt{background:var(--bg-alt);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.sec-head{display:grid;grid-template-columns:1fr .9fr;gap:48px;align-items:end;margin-bottom:56px}
.sec-label{
  display:inline-flex;align-items:center;gap:10px;
  font-family:var(--mono);font-size:.74rem;letter-spacing:.3em;color:var(--accent);text-transform:uppercase;margin-bottom:16px;
}
.sec-label::before{content:"";width:26px;height:1px;background:var(--accent)}
.sec-title{font-size:clamp(1.9rem,3.6vw,2.7rem);font-weight:800;letter-spacing:-.025em;line-height:1.15}
.sec-desc{color:var(--text-2);font-size:.98rem;max-width:440px;justify-self:end;border-left:2px solid var(--line-2);padding-left:20px}

/* ================= 兼容系统卡片 ================= */
.compat-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.compat-card{
  position:relative;background:var(--surface);border:1px solid var(--line);
  border-radius:var(--radius);padding:30px 26px;overflow:hidden;
  transition:border-color .2s,transform .2s var(--ease),background .2s;
}
.compat-card::before{
  content:"";position:absolute;left:0;top:0;bottom:0;width:3px;
  background:var(--accent);transform:scaleY(0);transform-origin:top;transition:transform .3s var(--ease);
}
.compat-card:hover{border-color:var(--accent-line);transform:translateY(-3px);background:var(--surface-2)}
.compat-card:hover::before{transform:scaleY(1)}
.compat-top{display:flex;align-items:center;justify-content:space-between;margin-bottom:22px}
.compat-icon{
  width:54px;height:54px;border:1px solid var(--line-2);border-radius:13px;
  display:flex;align-items:center;justify-content:center;color:var(--accent);
  background:var(--accent-dim);font-size:1.55rem;transition:transform .2s var(--ease),box-shadow .2s;
}
.compat-card:hover .compat-icon{transform:rotate(-4deg) scale(1.05);box-shadow:0 0 0 5px rgba(56,225,212,.08)}
.compat-idx{font-family:var(--mono);font-size:.78rem;color:var(--text-3);letter-spacing:.12em}
.compat-name{font-size:1.22rem;font-weight:700;letter-spacing:-.01em;margin-bottom:8px}
.compat-desc{font-size:.92rem;color:var(--text-2);line-height:1.75;margin-bottom:20px}
.compat-tag{
  display:inline-block;font-family:var(--mono);font-size:.7rem;letter-spacing:.14em;
  color:var(--accent-hi);background:var(--accent-dim);border:1px solid var(--accent-line);
  padding:5px 13px;border-radius:999px;
}

/* ================= 图集（便捷加载） ================= */
.gallery-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:22px}
.gallery-item{margin:0}
.gallery-img{
  position:relative;border:1px solid var(--line-2);border-radius:var(--radius);overflow:hidden;background:var(--surface);
  transition:border-color .2s,transform .2s var(--ease);
}
.gallery-item:hover .gallery-img{border-color:var(--accent-line);transform:translateY(-3px)}
.gallery-img img{width:100%;aspect-ratio:16/9;object-fit:cover;transition:transform .5s var(--ease)}
.gallery-item:hover .gallery-img img{transform:scale(1.03)}
.gallery-tag{
  position:absolute;top:14px;left:14px;font-family:var(--mono);font-size:.64rem;letter-spacing:.2em;
  color:var(--text);background:rgba(6,10,15,.78);border:1px solid var(--accent-line);
  padding:5px 11px;border-radius:6px;backdrop-filter:blur(4px);
}
.gallery-label{
  margin-top:14px;font-family:var(--mono);font-size:.8rem;letter-spacing:.16em;color:var(--text-2);
  display:flex;align-items:center;gap:10px;
}
.gallery-label::before{content:"";width:20px;height:1px;background:var(--accent)}

/* ================= 安装步骤 ================= */
.steps-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;counter-reset:step}
.step{position:relative;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:30px 24px 28px;transition:border-color .2s,transform .2s var(--ease),background .2s}
.step:hover{border-color:var(--accent-line);transform:translateY(-3px);background:var(--surface-2)}
.step-head{display:flex;align-items:center;gap:12px;margin-bottom:18px}
.step-no{
  font-family:var(--mono);font-size:1.5rem;font-weight:700;color:#060a0f;line-height:1;
  width:44px;height:44px;flex:none;border-radius:11px;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(135deg,var(--accent-hi),var(--accent));
  box-shadow:0 6px 16px rgba(56,225,212,.22);
}
.step-line{flex:1;height:1px;background:var(--line-2);position:relative}
.step-line::after{
  content:"";position:absolute;right:0;top:-2px;width:5px;height:5px;border-radius:50%;
  background:var(--accent);box-shadow:0 0 0 0 rgba(56,225,212,.5);animation:pulse 2.4s infinite;
}
.step-title{font-size:1.08rem;font-weight:700;margin-bottom:8px}
.step-desc{font-size:.88rem;color:var(--text-2);line-height:1.75}

/* ================= 页脚 ================= */
.footer{border-top:1px solid var(--line);background:var(--bg-alt)}
.footer-grid{
  display:grid;grid-template-columns:1.4fr repeat(3,1fr);gap:48px;padding:64px 0 48px;
}
.footer-brand .logo-mark{display:block;font-size:1.05rem;margin-bottom:14px}
.footer-desc{font-size:.86rem;color:var(--text-3);max-width:280px;line-height:1.8}
.footer-col-title{font-family:var(--mono);font-size:.72rem;letter-spacing:.26em;color:var(--text-3);text-transform:uppercase;margin-bottom:18px}
.footer-link{display:block;font-size:.9rem;color:var(--text-2);padding:5px 0;transition:color .15s,transform .15s}
.footer-link:hover{color:var(--accent-hi);transform:translateX(4px)}
.footer-bottom{
  display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;
  border-top:1px solid var(--line);padding:22px 0 30px;
  font-family:var(--mono);font-size:.74rem;letter-spacing:.08em;color:var(--text-3);
}
.footer-admin{color:var(--text-3);transition:color .15s}
.footer-admin:hover{color:var(--accent)}

/* ================= 响应式 ================= */
@media (max-width:1024px){
  .compat-grid{grid-template-columns:repeat(2,1fr)}
  .steps-grid{grid-template-columns:repeat(2,1fr)}
  .hero-grid{grid-template-columns:1fr;gap:44px}
  .hero-visual{justify-self:start;max-width:560px}
  .footer-grid{grid-template-columns:1fr 1fr;gap:36px}
}
@media (max-width:860px){
  .nav-inner{height:64px}
  .nav-toggle{display:flex}
  .nav-links{
    position:fixed;top:64px;right:0;bottom:0;width:min(320px,84vw);z-index:120;
    flex-direction:column;align-items:stretch;gap:2px;background:var(--bg-alt);
    border-left:1px solid var(--line-2);padding:20px 16px;transform:translateX(105%);
    transition:transform .32s var(--ease);
  }
  .nav-links.open{transform:none}
  .nav-link{font-size:1rem;padding:13px 14px}
  .nav-link::after{display:none}
  .nav-cta{margin:10px 0 0;justify-content:center;padding:13px}
  .sec-head{grid-template-columns:1fr;gap:20px}
  .sec-desc{justify-self:start;border-left:none;padding-left:0}
  .gallery-grid{grid-template-columns:1fr}
}
@media (max-width:560px){
  .container{padding:0 18px}
  .compat-grid{grid-template-columns:1fr}
  .steps-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .section{padding:76px 0}
  .hero-actions{flex-direction:column;align-items:stretch}
  .hero-actions .btn{width:100%}
}

/* ================= 无障碍 / 减少动效 ================= */
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.01ms !important;animation-iteration-count:1 !important;transition-duration:.01ms !important}
  html{scroll-behavior:auto}
  .reveal{opacity:1;transform:none}
}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:4px}