:root{
    --bg:#0b1020;
    --fg:#e9eefc;
    --muted:rgba(233,238,252,.78);
    --line:rgba(255,255,255,.10);
    --panel:rgba(255,255,255,.04);
    --panel-2:rgba(255,255,255,.02);
    --accent-a:#7c3aed;
    --accent-b:#22d3ee;
    --accent:linear-gradient(135deg,var(--accent-a),var(--accent-b));
    --radius:16px;
}
/* 重置 body padding，因为 landing-nav 是 sticky 的 */
body { padding-top: 0 !important; }

/* 仅针对 nav 的样式 */
.landing-nav{position:sticky;top:0;z-index:50;background:rgba(11,16,32,.80);backdrop-filter:saturate(180%) blur(14px);border-bottom:1px solid rgba(255,255,255,.08);}
.landing-nav .nav-inner{display:flex;align-items:center;justify-content:space-between;padding:26px 0;gap:18px;}
.brand{display:flex;align-items:center;gap:12px;font-weight:900;letter-spacing:.2px;white-space:nowrap;}
.brand .dot{width:14px;height:14px;border-radius:50%;background:var(--accent);box-shadow:0 0 0 8px rgba(124,58,237,.12);}
.brand .brand-name{font-size:24px;line-height:1; color: var(--fg);}
.brand .brand-sub{display:block;font-size:13px;opacity:.72;margin-top:8px;font-weight:700;letter-spacing:.1px; color: var(--fg);}
.nav-links{display:flex;flex-wrap:wrap;gap:10px;opacity:.94;align-items:center;justify-content:center;flex:1 1 auto;}
.nav-links a{opacity:.88;text-decoration:none;padding:10px 14px;border-radius:12px;font-weight:800;color: var(--fg);}
.nav-links a:hover{opacity:1;background:rgba(255,255,255,.06);}
.nav-badge{display:inline-block;margin-left:8px;padding:3px 8px;border-radius:999px;font-size:12px;line-height:1.4;background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.12);opacity:.9;}
details.nav-dd{position:relative;}
details.nav-dd summary{list-style:none;cursor:pointer;user-select:none;opacity:.88;padding:10px 14px;border-radius:12px;font-weight:800; color: var(--fg);}
details.nav-dd summary::-webkit-details-marker{display:none;}
details.nav-dd[open] summary{background:rgba(255,255,255,.06);opacity:1;}
details.nav-dd:hover summary{background:rgba(255,255,255,.06);opacity:1;}
.nav-menu{position:absolute;top:calc(100% + 10px);left:50%;transform:translateX(-50%);min-width:240px;border-radius:14px;background:rgba(11,16,32,.92);border:1px solid rgba(255,255,255,.12);box-shadow:0 18px 54px rgba(0,0,0,.28);padding:10px;z-index:60;}
.nav-menu a{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:10px 12px;border-radius:12px;text-decoration:none;opacity:.9;}
.nav-menu a:hover{background:rgba(255,255,255,.06);opacity:1;}
.nav-menu .hint{font-size:12px;opacity:.72;font-weight:700;}
.nav-cta{display:flex;align-items:center;gap:10px;flex-wrap:wrap;justify-content:flex-end;}
.nav-cta .btn{padding:12px 16px;font-weight:900;border-radius:12px;}
.btn-cta{background:var(--accent);border:none;color:#061022;font-weight:800;}
.btn-cta:hover{filter:brightness(1.05);color:#061022;}
.btn-ghost{background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.14);color:var(--fg);}
.btn-ghost:hover{background:rgba(255,255,255,.10);color:var(--fg);}
.btn-ghost:focus,.btn-cta:focus{outline:2px solid rgba(34,211,238,.55);outline-offset:2px;}
/* 响应式部分 */
@media (max-width: 768px){
    .landing-nav .nav-inner{align-items:flex-start;flex-direction:column;}
    .nav-links{width:100%;gap:8px;}
    .nav-links a, details.nav-dd summary{padding:10px 12px;background:rgba(255,255,255,.04);border:1px solid rgba(255,255,255,.08);}
    .nav-cta{width:100%;justify-content:flex-start;}
    .brand .brand-name{font-size:20px;}
    .nav-menu{position:static;transform:none;left:auto;top:auto;min-width:0;width:100%;margin-top:10px;}
}