/* ==========================================================================
   Premium 覆盖层（2026-10-28）
   目标：去掉"后台感"。少边框、大字、细线、噪点质感、单一强调色。
   ========================================================================== */

:root {
  --p-bg: #05070B;
  --p-ink: #F7F9FC;
  --p-mute: #8C97A8;
  --p-faint: #5A6577;
  --p-line: rgba(255, 255, 255, .085);
  --p-accent: #7DF9FF;
}

/* 背景：噪点 + 暗角，全站统一 */
body::after {
  content: "";
  position: fixed; inset: 0; z-index: 1; pointer-events: none; opacity: .05;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/></filter><rect width='160' height='160' filter='url(%23n)' opacity='0.55'/></svg>");
  mix-blend-mode: overlay;
}
body::before {
  content: ""; position: fixed; inset: 0; z-index: 0; pointer-events: none;
  background: radial-gradient(1200px 700px at 50% -10%, rgba(125, 249, 255, .07), transparent 62%),
              radial-gradient(900px 600px at 100% 100%, rgba(125, 249, 255, .04), transparent 60%);
}

/* 顶栏：贴边、细线、无玻璃拟态 */
.site-header { background: rgba(5, 7, 11, .72) !important; border-bottom: 1px solid var(--p-line) !important; }
.site-header .nav-link { font-size: 13.5px; color: var(--p-mute); letter-spacing: .01em; }
.site-header .nav-link.active, .site-header .nav-link:hover { color: var(--p-ink); }

/* 按钮：主按钮白底黑字，次按钮细线 */
.btn-primary, .btn.btn-primary {
  background: var(--p-ink) !important; color: #05070B !important; border: 1px solid var(--p-ink) !important;
  box-shadow: 0 10px 30px rgba(247, 249, 252, .12); font-weight: 700; letter-spacing: .01em;
}
.btn-primary:hover, .btn.btn-primary:hover { background: #fff !important; }
.btn-ghost, .btn.btn-ghost {
  background: transparent !important; color: var(--p-ink) !important; border: 1px solid rgba(255, 255, 255, .22) !important;
}
.btn-ghost:hover, .btn.btn-ghost:hover { border-color: var(--p-ink) !important; }

/* 首屏排版 */
.x-hero { background: var(--p-bg); }
.x-eyebrow {
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .28em; color: var(--p-mute);
  text-transform: uppercase; gap: 12px;
}
.x-eyebrow::before { width: 34px; background: linear-gradient(90deg, transparent, var(--p-mute)); }
.x-title {
  margin: 30px 0 0; font-size: clamp(52px, 7.4vw, 108px); line-height: .96; letter-spacing: -.045em; font-weight: 800;
  color: var(--p-ink);
  background: linear-gradient(180deg, #FFFFFF 30%, #A9B6C8 100%);
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent;
}
.x-title em {
  background: none; -webkit-text-fill-color: var(--p-ink); color: var(--p-ink);
  position: relative; white-space: nowrap;
}
.x-title em::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: .06em; height: 2px;
  background: linear-gradient(90deg, var(--p-accent), rgba(125, 249, 255, 0));
}
.x-sub { margin: 30px 0 0; font-size: 17px; line-height: 1.8; color: var(--p-mute); max-width: 540px; font-weight: 400; }
.x-cta { margin-top: 40px; gap: 16px; }
.x-cue { color: var(--p-faint); font-size: 10px; letter-spacing: .3em; }

/* 分节标题：编辑体，不再用胶囊标签 */
.sec-tag, .sec-head .sec-tag {
  background: none !important; border: 0 !important; padding: 0 !important; border-radius: 0 !important;
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .24em; text-transform: uppercase; color: var(--p-faint) !important;
}
.sec-tag .dot { display: none; }
.sec-head { margin-bottom: 64px !important; border-top: 1px solid var(--p-line); padding-top: 22px; }
.sec-head h2 {
  font-size: clamp(34px, 4vw, 56px) !important; line-height: 1.14 !important; letter-spacing: -.035em !important;
  font-weight: 800; color: var(--p-ink); margin: 16px 0 0 !important;
}
.sec-head .lede { color: var(--p-mute) !important; font-size: 16.5px !important; margin-top: 18px !important; max-width: 720px; }

/* 卡片：去边，靠层次 */
.glass, .tile, .x-cap, .case-card, .fact, .x-num, .ch-card, .x-diag, .x-fcard {
  border-color: transparent !important;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, .055), rgba(255, 255, 255, .012)) padding-box,
    linear-gradient(180deg, rgba(255, 255, 255, .12), rgba(255, 255, 255, 0)) border-box !important;
  border: 1px solid transparent !important;
  box-shadow: 0 1px 0 rgba(255, 255, 255, .04) inset, 0 24px 60px rgba(0, 0, 0, .35);
}
.tile h3, .x-cap h3, .case-card h4 { font-size: 19px; letter-spacing: -.01em; color: var(--p-ink); }
.tile p, .x-cap p, .case-card p { color: var(--p-mute); font-size: 14px; line-height: 1.8; }
.icon-box { background: rgba(255, 255, 255, .06) !important; border: 1px solid rgba(255, 255, 255, .1) !important; color: var(--p-ink) !important; }

/* 首屏信号图 */
.x-signal { width: 100%; height: auto; display: block; overflow: visible; }
.x-signal .lane { fill: none; stroke: rgba(255, 255, 255, .16); stroke-width: 1; }
.x-signal .flow { fill: none; stroke: url(#sg); stroke-width: 1.6; stroke-dasharray: 6 14; animation: flow 3.2s linear infinite; }
.x-signal .node { fill: #05070B; stroke: rgba(255, 255, 255, .38); stroke-width: 1.2; }
.x-signal .node-core { fill: var(--p-accent); }
.x-signal .lbl { fill: #F7F9FC; font-family: 'Noto Sans SC', system-ui, sans-serif; font-size: 17px; font-weight: 700; }
.x-signal .cap { fill: #6C7789; font-family: 'JetBrains Mono', monospace; font-size: 9.5px; letter-spacing: .18em; }
.x-signal .pulse { fill: var(--p-accent); filter: drop-shadow(0 0 6px rgba(125, 249, 255, .9)); }
@keyframes flow { to { stroke-dashoffset: -40; } }

/* 三段区 */
.x-scrub .x-panel h3 { font-size: clamp(28px, 3vw, 42px); letter-spacing: -.03em; line-height: 1.14; }
.x-panel .k { letter-spacing: .22em; font-size: 10.5px; color: var(--p-faint); }
.x-panel p { color: var(--p-mute); }
.x-panel li { color: var(--p-faint); }
.x-rail i { background: rgba(255, 255, 255, .12); }
.x-rail i.on::after { background: var(--p-accent); }

/* 数字 */
.x-nums { border: 0 !important; gap: 1px; background: var(--p-line) !important; border-radius: 18px; }
.x-num { background: #080B11 !important; }
.x-num .v { font-size: clamp(40px, 5vw, 68px); letter-spacing: -.04em; }
.x-num .l { color: var(--p-faint); }

/* 跑马灯 */
.x-marquee { border-color: var(--p-line) !important; padding: 26px 0; }
.x-marquee span { color: var(--p-faint); font-size: 12px; letter-spacing: .22em; }
.x-marquee span b { color: var(--p-accent); }

/* 收尾 */
.x-final { padding: 180px 0; }
.x-final h2 { font-size: clamp(44px, 6vw, 88px); letter-spacing: -.045em; }
.x-final p { color: var(--p-mute); }

/* 滚动进度线 */
#x-progress { position: fixed; left: 0; top: 0; height: 2px; width: 0; z-index: 60;
  background: linear-gradient(90deg, var(--p-accent), rgba(125, 249, 255, .2)); }

/* 页脚 */
.site-footer { background: #04060A !important; color: var(--p-faint); border-top: 1px solid var(--p-line); }
.foot-col-title { color: var(--p-ink) !important; }
.site-footer a { color: var(--p-mute); }
.site-footer a:hover { color: var(--p-ink); }
.x-title { font-size: clamp(44px, 5.4vw, 82px); }