/* ===== 基础 ===== */
:root {
  --bg: #03040c;
  --bg-2: #070a1c;
  --ink: #e8ecff;
  --ink-dim: #9aa4cc;
  --line: rgba(120, 150, 255, 0.14);
  --cyan: #36e0ff;
  --blue: #4b7bff;
  --violet: #9a6bff;
  --glow: 0 0 40px rgba(75, 123, 255, 0.35);
  --maxw: 1180px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: "Noto Sans SC", -apple-system, "Segoe UI", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }

/* 背景画布 */
#starfield {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  display: block;
}
.bg-overlay {
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background:
    radial-gradient(60% 50% at 50% 0%, rgba(75,123,255,0.10), transparent 70%),
    linear-gradient(180deg, transparent 0%, rgba(3,4,12,0.35) 55%, var(--bg) 92%);
}

/* 让正文内容压在画布之上 */
.nav, .hero, .section, .footer { position: relative; z-index: 2; }

/* ===== 通用元件 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: 999px;
  font-weight: 500;
  font-size: 15px;
  cursor: pointer;
  border: 1px solid transparent;
  transition: transform .25s ease, box-shadow .25s ease, background .25s ease;
  white-space: nowrap;
}
.btn-primary {
  background: linear-gradient(120deg, var(--cyan), var(--blue) 55%, var(--violet));
  color: #050816;
  font-weight: 700;
  box-shadow: var(--glow);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 0 55px rgba(75,123,255,.6); }
.btn-ghost {
  border-color: var(--line);
  color: var(--ink);
  background: rgba(120,150,255,0.05);
  backdrop-filter: blur(6px);
}
.btn-ghost:hover { transform: translateY(-2px); border-color: rgba(120,150,255,.45); background: rgba(120,150,255,0.12); }

.grad {
  background: linear-gradient(100deg, var(--cyan), var(--violet));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ===== 导航 ===== */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  transition: background .35s ease, border-color .35s ease, backdrop-filter .35s;
  border-bottom: 1px solid transparent;
}
.nav.scrolled {
  background: rgba(5, 7, 20, 0.72);
  backdrop-filter: blur(14px);
  border-bottom-color: var(--line);
}
.nav-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  gap: 24px;
}
.brand { display: flex; align-items: baseline; gap: 8px; }
.brand-mark { color: var(--cyan); font-size: 20px; text-shadow: 0 0 14px var(--cyan); }
.brand-name { font-weight: 700; font-size: 20px; letter-spacing: .5px; }
.brand-en { font-family: "Orbitron", sans-serif; font-size: 11px; color: var(--ink-dim); letter-spacing: 2px; }
.menu { margin-left: auto; display: flex; gap: 30px; }
.menu a { color: var(--ink-dim); font-size: 15px; transition: color .2s; }
.menu a:hover { color: var(--ink); }
.nav-cta { padding: 9px 20px; font-size: 14px; }
.menu-toggle { display: none; background: none; border: none; color: var(--ink); font-size: 24px; cursor: pointer; margin-left: auto; }

/* ===== 英雄区 ===== */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 120px 24px 60px;
}
.hero-content { max-width: 760px; }
.hero-eyebrow {
  display: inline-block;
  font-size: 13px;
  letter-spacing: 1px;
  color: var(--cyan);
  border: 1px solid var(--line);
  padding: 7px 16px;
  border-radius: 999px;
  margin-bottom: 28px;
  background: rgba(54,224,255,0.05);
}
.hero-title {
  font-size: clamp(34px, 6vw, 68px);
  line-height: 1.15;
  font-weight: 700;
  letter-spacing: .5px;
  margin-bottom: 24px;
}
.hero-sub {
  font-size: clamp(15px, 2vw, 19px);
  color: var(--ink-dim);
  max-width: 620px;
  margin-bottom: 38px;
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 60px; }
.hero-stats {
  display: flex;
  gap: 48px;
  flex-wrap: wrap;
}
.stat b {
  font-family: "Orbitron", sans-serif;
  font-size: clamp(26px, 4vw, 40px);
  font-weight: 700;
  background: linear-gradient(120deg, #fff, var(--cyan));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  display: block;
}
.stat span { font-size: 13px; color: var(--ink-dim); }

.scroll-hint {
  position: absolute;
  bottom: 28px; left: 50%;
  transform: translateX(-50%);
  font-size: 12px;
  color: var(--ink-dim);
  letter-spacing: 1px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}
.scroll-hint span {
  width: 22px; height: 36px;
  border: 1px solid var(--line);
  border-radius: 12px;
  position: relative;
}
.scroll-hint span::after {
  content: "";
  position: absolute;
  top: 7px; left: 50%;
  width: 4px; height: 6px;
  background: var(--cyan);
  border-radius: 2px;
  transform: translateX(-50%);
  animation: scrollDot 1.6s infinite;
}
@keyframes scrollDot { 0%{opacity:0;transform:translate(-50%,0)} 50%{opacity:1} 100%{opacity:0;transform:translate(-50%,12px)} }

/* ===== 通用区块 ===== */
.section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 100px 24px;
}
.section-head { text-align: center; max-width: 640px; margin: 0 auto 56px; }
.kicker { font-family: "Orbitron", sans-serif; font-size: 12px; letter-spacing: 3px; color: var(--cyan); margin-bottom: 14px; }
.section-head h2 { font-size: clamp(26px, 4vw, 42px); font-weight: 700; margin-bottom: 14px; }
.section-desc { color: var(--ink-dim); font-size: 16px; }

/* 卡片网格 */
.cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.card {
  padding: 32px 26px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: linear-gradient(180deg, rgba(120,150,255,0.06), rgba(120,150,255,0.01));
  transition: transform .3s ease, border-color .3s ease, box-shadow .3s;
}
.card:hover { transform: translateY(-6px); border-color: rgba(120,150,255,.4); box-shadow: var(--glow); }
.card-ico { font-size: 30px; margin-bottom: 16px; }
.card h3 { font-size: 19px; margin-bottom: 10px; }
.card p { color: var(--ink-dim); font-size: 14.5px; }

/* 套餐 */
.plans { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; align-items: stretch; }
.plan {
  position: relative;
  padding: 38px 30px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: linear-gradient(180deg, rgba(120,150,255,0.05), rgba(120,150,255,0.01));
  display: flex;
  flex-direction: column;
}
.plan-featured {
  border-color: rgba(75,123,255,.5);
  background: linear-gradient(180deg, rgba(75,123,255,0.14), rgba(120,150,255,0.02));
  box-shadow: var(--glow);
  transform: translateY(-12px);
}
.plan-tag {
  position: absolute; top: 18px; right: 18px;
  font-size: 12px; font-weight: 700;
  color: #050816;
  background: linear-gradient(120deg, var(--cyan), var(--violet));
  padding: 4px 12px; border-radius: 999px;
}
.plan-name { font-size: 18px; color: var(--ink-dim); margin-bottom: 12px; }
.plan-price { font-family: "Orbitron", sans-serif; font-size: 44px; font-weight: 700; margin-bottom: 22px; }
.plan-price span { font-size: 22px; vertical-align: super; margin-right: 2px; }
.plan-price small { font-size: 15px; color: var(--ink-dim); font-family: "Noto Sans SC"; font-weight: 400; }
.plan-list { list-style: none; margin-bottom: 28px; flex: 1; }
.plan-list li { padding: 9px 0; border-bottom: 1px dashed var(--line); font-size: 14.5px; color: var(--ink-dim); }
.plan-list li::before { content: "✦ "; color: var(--cyan); }
.plan-btn { justify-content: center; width: 100%; }

/* 数据中心节点 */
.nodes { display: flex; flex-wrap: wrap; gap: 14px; justify-content: center; }
.node {
  padding: 12px 22px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 15px;
  color: var(--ink-dim);
  background: rgba(120,150,255,0.04);
  transition: all .25s;
}
.node:hover { color: var(--ink); border-color: rgba(120,150,255,.45); transform: translateY(-3px); box-shadow: var(--glow); }

/* CTA */
.cta-section { padding-top: 40px; }
.cta-box {
  text-align: center;
  border: 1px solid var(--line);
  border-radius: 28px;
  padding: 64px 30px;
  background:
    radial-gradient(60% 120% at 50% 0%, rgba(75,123,255,0.18), transparent 70%),
    linear-gradient(180deg, rgba(120,150,255,0.05), rgba(120,150,255,0.01));
}
.cta-box h2 { font-size: clamp(26px, 4vw, 40px); margin-bottom: 14px; }
.cta-box > p { color: var(--ink-dim); margin-bottom: 32px; }
.cta-form { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; margin-bottom: 18px; }
.cta-form input {
  padding: 13px 20px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(5,7,20,0.6);
  color: var(--ink);
  font-size: 15px;
  min-width: 220px;
  outline: none;
}
.cta-form input:focus { border-color: var(--cyan); }
.cta-note { font-size: 13px; color: var(--ink-dim); }

/* ===== 页脚 ===== */
.footer { border-top: 1px solid var(--line); margin-top: 40px; background: rgba(3,4,12,0.6); }
.footer-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 50px 24px 24px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 24px;
}
.footer-brand { font-weight: 700; }
.footer-brand p { font-weight: 400; color: var(--ink-dim); font-size: 14px; margin-top: 10px; max-width: 360px; }
.footer-links { display: flex; gap: 26px; flex-wrap: wrap; align-items: center; }
.footer-links a { color: var(--ink-dim); font-size: 14px; transition: color .2s; }
.footer-links a:hover { color: var(--ink); }
.footer-copy {
  text-align: center;
  color: var(--ink-dim);
  font-size: 13px;
  padding: 20px;
  border-top: 1px solid var(--line);
}

/* 导航当前页 */
.menu a.active { color: var(--ink); }
.menu a.active::after {
  content: ""; display: block; height: 2px; margin-top: 4px;
  background: linear-gradient(90deg, var(--cyan), var(--violet));
  border-radius: 2px;
}

/* ===== 滚动进入动画 ===== */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ===== 信任背书 ===== */
.trust { position: relative; z-index: 2; max-width: var(--maxw); margin: 0 auto; padding: 30px 24px 10px; text-align: center; }
.trust-label { color: var(--ink-dim); font-size: 14px; margin-bottom: 20px; letter-spacing: 1px; }
.trust-logos { display: flex; flex-wrap: wrap; justify-content: center; gap: 14px 30px; }
.trust-logos span {
  color: var(--ink-dim); font-size: 16px; padding: 8px 18px;
  border: 1px solid var(--line); border-radius: 10px; background: rgba(120,150,255,0.03);
}

/* ===== 应用场景 ===== */
.scenes { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.scene {
  padding: 30px 24px; border: 1px solid var(--line); border-radius: 18px;
  background: linear-gradient(180deg, rgba(120,150,255,0.05), rgba(120,150,255,0.01));
  transition: transform .3s, border-color .3s, box-shadow .3s;
}
.scene:hover { transform: translateY(-6px); border-color: rgba(120,150,255,.4); box-shadow: var(--glow); }
.scene-ico { font-size: 32px; display: block; margin-bottom: 14px; }
.scene h3 { font-size: 18px; margin-bottom: 10px; }
.scene p { color: var(--ink-dim); font-size: 14.5px; }

/* ===== 服务流程 ===== */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.step { position: relative; padding: 30px 24px; border: 1px solid var(--line); border-radius: 18px; background: rgba(120,150,255,0.03); }
.step b {
  font-family: "Orbitron", sans-serif; font-size: 38px; font-weight: 900;
  background: linear-gradient(120deg, var(--cyan), var(--violet));
  -webkit-background-clip: text; background-clip: text; color: transparent;
  display: block; margin-bottom: 10px;
}
.step h3 { font-size: 18px; margin-bottom: 8px; }
.step p { color: var(--ink-dim); font-size: 14px; }

/* ===== 页面英雄（子页） ===== */
.page-hero {
  position: relative; z-index: 2; max-width: var(--maxw); margin: 0 auto;
  padding: 170px 24px 40px; text-align: center;
}
.page-hero h1 { font-size: clamp(30px, 5vw, 54px); font-weight: 700; margin-bottom: 18px; }
.page-hero-sub { color: var(--ink-dim); font-size: 17px; max-width: 640px; margin: 0 auto; }

/* ===== 配置对比表 ===== */
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 18px; }
.spec-table { width: 100%; border-collapse: collapse; min-width: 620px; }
.spec-table th, .spec-table td { padding: 16px 20px; text-align: left; font-size: 15px; border-bottom: 1px solid var(--line); }
.spec-table thead th { font-weight: 700; color: var(--ink); background: rgba(120,150,255,0.06); }
.spec-table td:first-child { color: var(--ink-dim); }
.spec-table th.hl, .spec-table td.hl { background: rgba(75,123,255,0.10); color: var(--ink); }
.spec-table tbody tr:last-child td { border-bottom: none; }

/* ===== FAQ ===== */
.faq-list { max-width: 760px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq-item { border: 1px solid var(--line); border-radius: 14px; overflow: hidden; background: rgba(120,150,255,0.03); }
.faq-q {
  width: 100%; text-align: left; background: none; border: none; color: var(--ink);
  font-size: 16px; padding: 18px 22px; cursor: pointer; display: flex; justify-content: space-between; align-items: center;
  font-family: inherit;
}
.faq-q span { color: var(--cyan); font-size: 22px; transition: transform .3s; }
.faq-item.open .faq-q span { transform: rotate(45deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height .35s ease; }
.faq-a p { padding: 0 22px 18px; color: var(--ink-dim); font-size: 14.5px; }

/* ===== 地球英雄 ===== */
.globe-hero {
  position: relative; z-index: 2; max-width: var(--maxw); margin: 0 auto;
  padding: 150px 24px 40px; display: grid; grid-template-columns: 1fr 1fr; gap: 30px; align-items: center; min-height: 90vh;
}
.globe-text h1 { font-size: clamp(30px, 4.6vw, 52px); font-weight: 700; margin-bottom: 18px; }
.globe-wrap { position: relative; aspect-ratio: 1; max-width: 520px; width: 100%; margin: 0 auto; }
#globe { width: 100%; height: 100%; display: block; }

/* ===== 节点网格 ===== */
.node-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.node-card {
  padding: 22px; border: 1px solid var(--line); border-radius: 16px;
  background: linear-gradient(180deg, rgba(120,150,255,0.05), rgba(120,150,255,0.01));
  transition: transform .3s, border-color .3s, box-shadow .3s;
}
.node-card:hover { transform: translateY(-5px); border-color: rgba(120,150,255,.45); box-shadow: var(--glow); }
.node-card b { font-size: 20px; display: block; margin-bottom: 6px; }
.node-card span { color: var(--ink-dim); font-size: 13.5px; }

/* ===== 指标条 ===== */
.metrics { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; text-align: center;
  border: 1px solid var(--line); border-radius: 22px; padding: 40px 20px;
  background: linear-gradient(180deg, rgba(120,150,255,0.05), rgba(120,150,255,0.01)); }
.metric b, .about-metrics b, .metrics b {
  font-family: "Orbitron", sans-serif; font-size: clamp(28px, 4vw, 44px); font-weight: 700;
  background: linear-gradient(120deg, #fff, var(--cyan)); -webkit-background-clip: text; background-clip: text; color: transparent; display: block;
}
.metric span { color: var(--ink-dim); font-size: 14px; }

/* ===== 关于：简介 + 数据 ===== */
.about-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 40px; align-items: center; }
.about-text h2 { font-size: clamp(24px, 3.4vw, 36px); margin-bottom: 18px; }
.about-text p { color: var(--ink-dim); margin-bottom: 16px; }
.about-metrics { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.about-metrics > div { padding: 24px; border: 1px solid var(--line); border-radius: 16px; text-align: center; background: rgba(120,150,255,0.03); }
.about-metrics span { color: var(--ink-dim); font-size: 13.5px; }

/* ===== 时间线 ===== */
.timeline { max-width: 760px; margin: 0 auto; position: relative; padding-left: 28px; }
.timeline::before { content: ""; position: absolute; left: 6px; top: 6px; bottom: 6px; width: 2px;
  background: linear-gradient(180deg, var(--cyan), var(--violet)); opacity: .5; }
.tl-item { position: relative; padding: 0 0 34px 24px; }
.tl-item::before { content: ""; position: absolute; left: -28px; top: 4px; width: 14px; height: 14px; border-radius: 50%;
  background: var(--cyan); box-shadow: 0 0 14px var(--cyan); }
.tl-item b { font-family: "Orbitron", sans-serif; color: var(--cyan); font-size: 18px; }
.tl-item h3 { font-size: 19px; margin: 4px 0 6px; }
.tl-item p { color: var(--ink-dim); font-size: 14.5px; }

/* ===== 联系页 ===== */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 36px; align-items: start; }
.contact-info h2 { font-size: clamp(24px, 3.4vw, 36px); margin-bottom: 20px; }
.contact-line { color: var(--ink-dim); margin-bottom: 14px; font-size: 15.5px; }
.contact-line b { color: var(--ink); }
.contact-form { padding: 32px; border: 1px solid var(--line); border-radius: 20px; background: rgba(120,150,255,0.04); display: flex; flex-direction: column; gap: 14px; }
.contact-form h3 { font-size: 20px; margin-bottom: 4px; }
.contact-form input, .contact-form textarea {
  padding: 13px 18px; border-radius: 12px; border: 1px solid var(--line);
  background: rgba(5,7,20,0.6); color: var(--ink); font-size: 15px; outline: none; font-family: inherit; resize: vertical;
}
.contact-form input:focus, .contact-form textarea:focus { border-color: var(--cyan); }

/* ===== 页脚多列 ===== */
.footer-cols { display: flex; gap: 60px; flex-wrap: wrap; }
.footer-col h4 { font-size: 14px; margin-bottom: 14px; color: var(--ink); }
.footer-col a { display: block; color: var(--ink-dim); font-size: 14px; margin-bottom: 10px; transition: color .2s; }
.footer-col a:hover { color: var(--ink); }

/* ===== 响应式 ===== */
@media (max-width: 980px) {
  .globe-hero { grid-template-columns: 1fr; text-align: center; }
  .globe-text .hero-actions { justify-content: center; }
  .globe-wrap { max-width: 420px; }
  .about-grid, .contact-grid { grid-template-columns: 1fr; }
}
@media (max-width: 900px) {
  .cards { grid-template-columns: repeat(2, 1fr); }
  .scenes, .steps, .node-grid { grid-template-columns: repeat(2, 1fr); }
  .metrics { grid-template-columns: repeat(2, 1fr); }
  .plans { grid-template-columns: 1fr; max-width: 440px; margin: 0 auto; }
  .plan-featured { transform: none; }
  .menu { display: none; }
  .nav-cta { display: none; }
  .menu-toggle { display: block; }
  .menu.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px; left: 0; right: 0;
    background: rgba(5,7,20,0.95);
    backdrop-filter: blur(14px);
    padding: 20px 24px;
    gap: 18px;
    border-bottom: 1px solid var(--line);
  }
}
@media (max-width: 560px) {
  .cards, .scenes, .steps, .node-grid { grid-template-columns: 1fr; }
  .about-metrics { grid-template-columns: 1fr 1fr; }
  .hero-stats { gap: 28px; }
  .hero { padding-top: 100px; }
  .footer-cols { gap: 36px; }
}

/* 尊重「减少动态效果」偏好 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .scroll-hint span::after { animation: none; }
}