/* ============================================================
   zh-offical 官网样式 —— 筑幻工坊（运营主体：苏州筑幻软件开发有限公司）
   主题：暗冷科幻 · 渐变霓虹
   规范：类名 kebab-case；无构建步骤，由各 HTML 直接引用
   ============================================================ */

:root {
  --color-bg: #05080f;
  --color-surface: rgba(15, 23, 42, 0.55);
  --color-border: rgba(103, 232, 249, 0.16);
  --color-text: #dbe7ff;
  --color-text-muted: #8fa3c8;
  --gradient-brand: linear-gradient(120deg, #22d3ee 0%, #60a5fa 45%, #a78bfa 100%);
  --gradient-cta: linear-gradient(120deg, #0891b2 0%, #3b82f6 55%, #7c3aed 100%);
  --glow-cyan: rgba(34, 211, 238, 0.35);
  --glow-violet: rgba(139, 92, 246, 0.35);
  --radius: 14px;
  --container: 1080px;
}

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

html {
  color-scheme: dark;
  scroll-behavior: smooth;
}

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, sans-serif;
  color: var(--color-text);
  background:
    radial-gradient(1200px 600px at 85% -10%, rgba(59, 130, 246, 0.16), transparent 60%),
    radial-gradient(900px 520px at 8% 12%, rgba(34, 211, 238, 0.10), transparent 55%),
    radial-gradient(1100px 720px at 50% 115%, rgba(139, 92, 246, 0.14), transparent 60%),
    var(--color-bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* 科幻网格背景（固定全屏，不挡交互） */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(96, 165, 250, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(96, 165, 250, 0.05) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 20%, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 90% 70% at 50% 20%, #000 30%, transparent 75%);
}

::selection {
  background: rgba(34, 211, 238, 0.3);
}

a {
  color: #67e8f9;
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: #a5f3fc;
}

img {
  max-width: 100%;
  height: auto;
}

.container {
  position: relative;
  z-index: 1;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- 渐变文字 ---------- */
.gradient-text {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(5, 8, 15, 0.75);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--color-border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.brand {
  font-size: 21px;
  font-weight: 700;
  letter-spacing: 2px;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: 10px;
}

.brand .brand-mark {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.nav-links {
  display: flex;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  color: var(--color-text-muted);
  font-size: 15px;
  letter-spacing: 1px;
  position: relative;
  padding: 6px 0;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 1.5px;
  background: var(--gradient-brand);
  transition: width 0.25s;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  color: #a5f3fc;
}

.nav-links a:hover::after,
.nav-links a[aria-current="page"]::after {
  width: 100%;
}

/* ---------- 主体区块 ---------- */
main {
  min-height: calc(100vh - 68px - 96px);
}

section {
  padding: 88px 0;
}

.section-title {
  font-size: 32px;
  font-weight: 800;
  text-align: center;
  letter-spacing: 2px;
  margin-bottom: 14px;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.section-subtitle {
  text-align: center;
  color: var(--color-text-muted);
  max-width: 660px;
  margin: 0 auto 56px;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  text-align: center;
  padding: 120px 0 104px;
}

/* 光晕 orb */
.hero::before,
.hero::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  filter: blur(100px);
  z-index: 0;
  pointer-events: none;
}

.hero::before {
  width: 420px;
  height: 420px;
  background: rgba(34, 211, 238, 0.16);
  top: -120px;
  left: -60px;
  animation: drift 14s ease-in-out infinite alternate;
}

.hero::after {
  width: 480px;
  height: 480px;
  background: rgba(139, 92, 246, 0.18);
  bottom: -180px;
  right: -80px;
  animation: drift 18s ease-in-out infinite alternate-reverse;
}

@keyframes drift {
  from { transform: translate(0, 0) scale(1); }
  to   { transform: translate(40px, 24px) scale(1.15); }
}

/* 星空粒子容器（由 main.js 填充） */
.starfield {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
}

.starfield i {
  position: absolute;
  background: #cfe8ff;
  border-radius: 50%;
  opacity: 0.5;
  animation: twinkle 3s ease-in-out infinite;
}

@keyframes twinkle {
  0%, 100% { opacity: 0.12; }
  50%      { opacity: 0.85; }
}

.hero .container {
  z-index: 1;
}

.hero-overline {
  display: inline-block;
  font-size: 13px;
  letter-spacing: 5px;
  text-transform: uppercase;
  color: #67e8f9;
  border: 1px solid rgba(103, 232, 249, 0.35);
  border-radius: 999px;
  padding: 6px 18px;
  margin-bottom: 28px;
  background: rgba(34, 211, 238, 0.06);
  box-shadow: 0 0 22px rgba(34, 211, 238, 0.15) inset;
}

.hero h1 {
  font-size: 56px;
  font-weight: 800;
  letter-spacing: 8px;
  margin-bottom: 16px;
  text-shadow: 0 0 40px rgba(96, 165, 250, 0.35);
}

.hero .company-name {
  font-size: 18px;
  color: var(--color-text-muted);
  letter-spacing: 4px;
  margin-bottom: 24px;
}

.hero .tagline {
  font-size: 17px;
  color: var(--color-text-muted);
  max-width: 660px;
  margin: 0 auto 44px;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-block;
  background: var(--gradient-cta);
  background-size: 160% 100%;
  color: #fff;
  padding: 14px 34px;
  border-radius: 999px;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 2px;
  border: none;
  cursor: pointer;
  box-shadow: 0 0 20px rgba(59, 130, 246, 0.35);
  transition: transform 0.2s, box-shadow 0.2s, background-position 0.4s;
}

.btn:hover {
  color: #fff;
  transform: translateY(-2px);
  background-position: 100% 0;
  box-shadow: 0 0 34px rgba(34, 211, 238, 0.45);
}

.btn.btn-ghost {
  background: transparent;
  color: #7dd3fc;
  border: 1.5px solid rgba(103, 232, 249, 0.5);
  box-shadow: none;
  margin-left: 14px;
}

.btn.btn-ghost:hover {
  background: rgba(34, 211, 238, 0.08);
  box-shadow: 0 0 22px rgba(34, 211, 238, 0.2);
}

/* ---------- 特性卡片 ---------- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 26px;
}

.feature-card {
  background: var(--color-surface);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: transform 0.25s, box-shadow 0.25s, border-color 0.25s;
}

.feature-card:hover {
  transform: translateY(-5px);
  border-color: rgba(103, 232, 249, 0.45);
  box-shadow: 0 10px 44px rgba(34, 211, 238, 0.12), 0 0 0 1px rgba(103, 232, 249, 0.08);
}

.feature-card .card-icon {
  font-size: 30px;
  margin-bottom: 16px;
  display: block;
}

.feature-card h3 {
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 1px;
  margin-bottom: 10px;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.feature-card p {
  color: var(--color-text-muted);
  font-size: 15px;
}

/* ---------- 内容页（关于 / 联系） ---------- */
.page-hero {
  position: relative;
  overflow: hidden;
  padding: 92px 0 64px;
  text-align: center;
}

.page-hero .container {
  z-index: 1;
}

.page-hero h1 {
  font-size: 40px;
  font-weight: 800;
  letter-spacing: 4px;
  margin-bottom: 12px;
  text-shadow: 0 0 36px rgba(96, 165, 250, 0.3);
}

.page-hero p {
  color: var(--color-text-muted);
  letter-spacing: 2px;
}

.prose {
  max-width: 780px;
  margin: 0 auto;
}

.prose h2 {
  font-size: 24px;
  font-weight: 700;
  margin: 44px 0 14px;
  letter-spacing: 1px;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.prose p {
  color: var(--color-text-muted);
  margin-bottom: 14px;
}

/* ---------- 联系信息 / 表单 ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 26px;
}

.contact-info-card {
  background: var(--color-surface);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 28px;
}

.contact-info-card h3 {
  font-size: 17px;
  margin-bottom: 12px;
  color: #a5f3fc;
  letter-spacing: 1px;
}

.contact-info-card p {
  color: var(--color-text-muted);
  font-size: 15px;
  margin-bottom: 6px;
}

.contact-form {
  max-width: 600px;
  margin: 0 auto;
  background: var(--color-surface);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 36px;
  box-shadow: 0 0 40px rgba(34, 211, 238, 0.06);
}

.contact-form label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: #a5f3fc;
  margin: 18px 0 8px;
  letter-spacing: 1px;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--color-border);
  border-radius: 10px;
  font-size: 15px;
  font-family: inherit;
  color: var(--color-text);
  background: rgba(2, 6, 23, 0.6);
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.contact-form input:focus,
.contact-form textarea:focus {
  border-color: rgba(103, 232, 249, 0.6);
  box-shadow: 0 0 0 3px rgba(34, 211, 238, 0.15);
}

.contact-form textarea {
  min-height: 130px;
  resize: vertical;
}

.contact-form button {
  margin-top: 28px;
  width: 100%;
}

/* ---------- 页脚 ---------- */
.site-footer {
  position: relative;
  z-index: 1;
  border-top: 1px solid var(--color-border);
  padding: 28px 0;
  text-align: center;
  color: var(--color-text-muted);
  font-size: 14px;
  letter-spacing: 1px;
}

.site-footer p {
  margin: 2px 0;
}

/* 备案号链接：页脚内保持低调配色，hover 提亮 */
.site-footer a {
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color 0.2s;
}

.site-footer a:hover {
  color: #a5f3fc;
}

/* ---------- 滚动显现（仅 JS 可用时生效，见 .js 前缀） ---------- */
.js .reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.js .reveal.visible {
  opacity: 1;
  transform: none;
}

/* ---------- 响应式 ---------- */
@media (max-width: 720px) {
  .hero h1 {
    font-size: 34px;
    letter-spacing: 4px;
  }

  .page-hero h1 {
    font-size: 30px;
  }

  .nav-links {
    gap: 18px;
  }

  section {
    padding: 56px 0;
  }

  .btn.btn-ghost {
    margin-left: 0;
    margin-top: 12px;
  }
}