/* ==========================================================================
   深圳市居亭科技有限公司 - 企业官网样式
   纯静态 CSS，无任何外部依赖；所有图片为占位链接，替换方式见 images/README.txt
   ========================================================================== */

/* ---------- 设计变量 ---------- */
:root {
  --primary: #0b4a8f;        /* 主色：深蓝 */
  --primary-600: #1263b0;    /* 主色亮阶 */
  --primary-dark: #072f5f;   /* 主色暗阶 */
  --accent: #f5861f;         /* 强调色：橙 */
  --accent-dark: #d97108;
  --bg-light: #f5f7fb;       /* 浅灰蓝背景 */
  --text: #2b2f36;
  --text-light: #5d6675;
  --border: #e3e8ef;
  --white: #ffffff;
  --radius: 12px;
  --shadow: 0 8px 28px rgba(11, 74, 143, 0.10);
  --shadow-lg: 0 16px 44px rgba(11, 74, 143, 0.16);
  --maxw: 1200px;
}

/* ---------- 基础重置 ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; scroll-padding-top: 88px; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: var(--white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

.section { padding: 84px 0; }
.section--light { background: var(--bg-light); }

.section-head { text-align: center; max-width: 700px; margin: 0 auto 52px; }
.section-head .sub {
  display: inline-block; color: var(--primary); font-weight: 700;
  letter-spacing: 3px; font-size: 13px; margin-bottom: 10px;
}
.section-head h2 { font-size: clamp(26px, 4vw, 34px); color: var(--primary-dark); margin-bottom: 14px; }
.section-head p { color: var(--text-light); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-block; padding: 13px 30px; border-radius: 999px;
  font-size: 15px; font-weight: 600; text-align: center;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn-primary { background: var(--accent); color: #fff; box-shadow: 0 6px 18px rgba(245, 134, 31, .35); }
.btn-primary:hover { background: var(--accent-dark); }

.btn-blue { background: var(--primary); color: #fff; box-shadow: 0 6px 18px rgba(11, 74, 143, .30); }
.btn-blue:hover { background: var(--primary-600); }

.btn-ghost { background: rgba(255, 255, 255, .14); color: #fff; border: 1px solid rgba(255, 255, 255, .75); }
.btn-ghost:hover { background: rgba(255, 255, 255, .26); }

.btn-outline { background: transparent; color: var(--primary); border: 1px solid var(--primary); }
.btn-outline:hover { background: var(--primary); color: #fff; }

/* ---------- 顶部导航（sticky，不依赖 JS 也能正常显示） ---------- */
.header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, .96);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 2px 10px rgba(11, 74, 143, .04);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 76px; }

.logo { display: flex; align-items: center; gap: 12px; }
.logo-mark { display: flex; }
.logo-text { display: flex; flex-direction: column; line-height: 1.2; }
.logo-text strong { font-size: 19px; color: var(--primary-dark); letter-spacing: .5px; }
.logo-text small { font-size: 11px; color: var(--text-light); letter-spacing: 1.6px; }

.nav { display: flex; gap: 8px; }
.nav-link {
  display: block; padding: 9px 18px; border-radius: 999px;
  font-size: 15px; color: var(--text); font-weight: 500; transition: color .2s ease, background .2s ease;
}
.nav-link:hover { color: var(--primary); background: var(--bg-light); }
.nav-link.active { color: #fff; background: var(--primary); }

/* 移动端汉堡按钮 */
.nav-toggle { display: none; flex-direction: column; gap: 5px; padding: 8px; }
.nav-toggle span { width: 22px; height: 2px; background: var(--primary-dark); border-radius: 2px; transition: transform .25s ease, opacity .25s ease; }
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* 中英文语言切换按钮 */
.lang-switch {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 46px; padding: 8px 15px; margin-left: 8px;
  border-radius: 999px; border: 1px solid var(--primary);
  font-size: 13px; font-weight: 600; color: var(--primary);
  background: var(--white); letter-spacing: .5px;
  transition: background .2s ease, color .2s ease;
}
.lang-switch:hover { background: var(--primary); color: #fff; }

/* ---------- 首页 Hero 轮播 ---------- */
.hero { position: relative; height: min(640px, 82vh); min-height: 460px; overflow: hidden; background: var(--primary-dark); }
.hero-slider, .slide { position: absolute; inset: 0; }
.hero-slider { z-index: 1; }

.slide { opacity: 0; visibility: hidden; transition: opacity .8s ease, visibility .8s ease; }
.slide.active { opacity: 1; visibility: visible; z-index: 1; }

.slide-bg {
  position: absolute; inset: 0; width: 100%; height: 100%;
  object-fit: cover; transform: scale(1.10);
  transition: transform 7s linear;
}
.slide.active .slide-bg { transform: scale(1); }

.slide-overlay { position: absolute; inset: 0; background: linear-gradient(100deg, rgba(6, 30, 62, .82) 20%, rgba(6, 30, 62, .42) 70%, rgba(6, 30, 62, .30)); }

.slide-content {
  position: absolute; inset: 0; z-index: 2;
  display: flex; flex-direction: column; justify-content: center; align-items: flex-start;
  max-width: var(--maxw); margin: 0 auto; padding: 0 20px; color: #fff;
}
.slide-tag {
  display: inline-block; padding: 6px 16px; border: 1px solid rgba(255, 255, 255, .6);
  border-radius: 999px; font-size: 13px; letter-spacing: 3px; margin-bottom: 20px;
}
.slide-content h1 { font-size: clamp(30px, 5vw, 48px); line-height: 1.25; margin-bottom: 16px; max-width: 680px; }
.slide-desc { font-size: clamp(15px, 2vw, 18px); color: rgba(255, 255, 255, .9); max-width: 560px; margin-bottom: 30px; }
.slide-actions { display: flex; gap: 14px; flex-wrap: wrap; }

.hero-arrow {
  position: absolute; top: 50%; transform: translateY(-50%); z-index: 3;
  width: 46px; height: 46px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 18px; color: #fff; background: rgba(255, 255, 255, .16);
  border: 1px solid rgba(255, 255, 255, .45); transition: background .2s ease;
}
.hero-arrow:hover { background: rgba(255, 255, 255, .32); }
.hero-prev { left: 20px; }
.hero-next { right: 20px; }

.hero-dots {
  position: absolute; left: 50%; transform: translateX(-50%); bottom: 26px; z-index: 3;
  display: flex; gap: 10px;
}
.hero-dots .dot { width: 10px; height: 10px; border-radius: 999px; background: rgba(255, 255, 255, .45); transition: width .25s ease, background .25s ease; }
.hero-dots .dot.active { width: 26px; background: #fff; }

/* ---------- 公司简介条 ---------- */
.intro { display: grid; grid-template-columns: 1.05fr 1fr; gap: 56px; align-items: center; }
.intro-media { position: relative; }
.intro-media img { border-radius: var(--radius); box-shadow: var(--shadow-lg); width: 100%; }
.intro-media .badge {
  position: absolute; left: 18px; bottom: 18px;
  background: var(--accent); color: #fff; border-radius: var(--radius);
  padding: 14px 20px; text-align: center; box-shadow: var(--shadow);
}
.intro-media .badge strong { display: block; font-size: 26px; line-height: 1.2; }
.intro-media .badge span { font-size: 13px; }

.intro-text h2 { font-size: clamp(24px, 3.4vw, 32px); color: var(--primary-dark); margin-bottom: 16px; }
.intro-text > p { color: var(--text-light); margin-bottom: 20px; }
.intro-points { margin: 22px 0 28px; display: grid; gap: 12px; }
.intro-points li { display: flex; gap: 10px; align-items: flex-start; }
.intro-points .tick {
  flex: none; width: 20px; height: 20px; margin-top: 4px; border-radius: 50%;
  background: rgba(11, 74, 143, .10); color: var(--primary);
  display: flex; align-items: center; justify-content: center; font-size: 12px; font-weight: 700;
}

/* ---------- 服务卡片 ---------- */
.cards-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.card {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 32px 28px; box-shadow: var(--shadow);
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}
.card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: rgba(11, 74, 143, .35); }
.card .icon { width: 48px; height: 48px; margin-bottom: 18px; stroke: var(--primary); fill: none; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.card h3 { font-size: 19px; color: var(--primary-dark); margin-bottom: 10px; }
.card p { font-size: 14.5px; color: var(--text-light); }
.card .more { display: inline-block; margin-top: 16px; color: var(--primary); font-size: 14px; font-weight: 600; }
.card .more:hover { color: var(--accent); }

/* ---------- 数据条 ---------- */
.stats-band { background: linear-gradient(120deg, var(--primary-dark), var(--primary-600)); color: #fff; }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; text-align: center; }
.stat strong { display: block; font-size: clamp(30px, 4vw, 42px); font-weight: 800; }
.stat span { color: rgba(255, 255, 255, .82); font-size: 14px; }
.stats-note { text-align: center; margin-top: 22px; font-size: 12.5px; color: rgba(255, 255, 255, .55); }

/* ---------- 优势卡片 ---------- */
.features-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.feature {
  background: var(--white); border-radius: var(--radius); border: 1px solid var(--border);
  padding: 28px 22px; text-align: center; transition: transform .25s ease, box-shadow .25s ease;
}
.feature:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.feature .f-num {
  width: 44px; height: 44px; margin: 0 auto 14px; border-radius: 12px;
  background: rgba(11, 74, 143, .08); color: var(--primary);
  display: flex; align-items: center; justify-content: center; font-weight: 800; font-size: 18px;
}
.feature h3 { font-size: 17px; color: var(--primary-dark); margin-bottom: 8px; }
.feature p { font-size: 13.5px; color: var(--text-light); }

/* ---------- CTA 横幅 ---------- */
.cta-band { background: linear-gradient(120deg, var(--primary), var(--primary-600)); color: #fff; text-align: center; }
.cta-band h2 { font-size: clamp(24px, 3.4vw, 32px); margin-bottom: 12px; }
.cta-band p { color: rgba(255, 255, 255, .85); margin-bottom: 26px; }
.cta-band .btn { margin: 0 7px; }

/* ---------- 内页横幅 ---------- */
.page-banner {
  background: linear-gradient(120deg, var(--primary-dark), var(--primary-600));
  color: #fff; text-align: center; padding: 76px 20px 66px;
}
.page-banner h1 { font-size: clamp(28px, 4vw, 38px); margin-bottom: 8px; }
.page-banner p { color: rgba(255, 255, 255, .85); }
.crumb { font-size: 13px; color: rgba(255, 255, 255, .7); margin-top: 12px; }
.crumb a:hover { color: #fff; }

/* ---------- 关于页 ---------- */
.about-grid { display: grid; grid-template-columns: 1fr 1.05fr; gap: 56px; align-items: center; }
.about-grid img { border-radius: var(--radius); box-shadow: var(--shadow-lg); width: 100%; }
.about-grid h2 { font-size: clamp(24px, 3.4vw, 32px); color: var(--primary-dark); margin-bottom: 16px; }
.about-grid p { color: var(--text-light); margin-bottom: 14px; }

.values-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }

/* 发展历程时间线 */
.timeline { position: relative; max-width: 820px; margin: 0 auto; padding-left: 34px; }
.timeline::before { content: ""; position: absolute; left: 9px; top: 6px; bottom: 6px; width: 2px; background: var(--border); }
.timeline-item { position: relative; padding-bottom: 34px; }
.timeline-item::before {
  content: ""; position: absolute; left: -31px; top: 6px;
  width: 14px; height: 14px; border-radius: 50%;
  background: var(--white); border: 3px solid var(--primary);
}
.timeline-item .year { color: var(--primary); font-weight: 800; font-size: 16px; }
.timeline-item h3 { color: var(--primary-dark); font-size: 17px; margin: 2px 0 6px; }
.timeline-item p { color: var(--text-light); font-size: 14.5px; }

/* ---------- 服务流程 ---------- */
.steps-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; counter-reset: step; }
.step {
  position: relative; background: var(--white); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 30px 22px 26px; text-align: center; box-shadow: var(--shadow);
}
.step::before {
  counter-increment: step; content: counter(step, decimal-leading-zero);
  font-size: 40px; font-weight: 800; color: rgba(11, 74, 143, .14); line-height: 1;
}
.step h3 { font-size: 16px; color: var(--primary-dark); margin: 12px 0 8px; }
.step p { font-size: 13.5px; color: var(--text-light); }

/* ---------- 联系页 ---------- */
.contact-cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.contact-card {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 30px 22px; text-align: center; box-shadow: var(--shadow);
  transition: transform .25s ease, box-shadow .25s ease;
}
.contact-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-lg); }
.contact-card .c-icon {
  width: 50px; height: 50px; margin: 0 auto 16px; border-radius: 50%;
  background: rgba(11, 74, 143, .08); display: flex; align-items: center; justify-content: center;
}
.contact-card .c-icon svg { width: 24px; height: 24px; stroke: var(--primary); fill: none; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.contact-card h3 { font-size: 15px; color: var(--text-light); font-weight: 600; margin-bottom: 8px; }
.contact-card .c-val { font-size: 17px; color: var(--primary-dark); font-weight: 700; word-break: break-all; }
.contact-card .c-note { font-size: 12.5px; color: var(--text-light); margin-top: 6px; }

.contact-split { display: grid; grid-template-columns: 1.1fr 1fr; gap: 44px; align-items: center; }
.contact-tip h2 { font-size: clamp(22px, 3vw, 30px); color: var(--primary-dark); margin-bottom: 16px; }
.contact-tip p { color: var(--text-light); margin-bottom: 14px; }
.contact-tip ul { display: grid; gap: 12px; }
.contact-tip li { display: flex; gap: 10px; align-items: flex-start; }
.contact-tip .tick { flex: none; width: 20px; height: 20px; margin-top: 4px; border-radius: 50%; background: rgba(11, 74, 143, .10); color: var(--primary); display: flex; align-items: center; justify-content: center; font-size: 12px; font-weight: 700; }

.qr-box {
  background: var(--white); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 30px; text-align: center; box-shadow: var(--shadow);
}
.qr-box img { width: 220px; height: 220px; margin: 0 auto 16px; border-radius: 8px; border: 1px solid var(--border); }
.qr-box h3 { color: var(--primary-dark); font-size: 17px; margin-bottom: 6px; }
.qr-box p { color: var(--text-light); font-size: 13.5px; }
.qr-box .tag { display: inline-block; margin-top: 12px; padding: 4px 14px; border-radius: 999px; background: rgba(245, 134, 31, .12); color: var(--accent-dark); font-size: 12.5px; font-weight: 600; }

/* ---------- 页脚 ---------- */
.footer { background: #08203c; color: rgba(255, 255, 255, .78); }
.footer-grid { display: grid; grid-template-columns: 1.3fr 1fr 1.2fr; gap: 44px; padding: 60px 0 44px; }
.footer h3 { color: #fff; font-size: 16px; margin-bottom: 18px; }
.footer-about .logo-text strong { color: #fff; }
.footer-about p { font-size: 14px; margin-top: 14px; color: rgba(255, 255, 255, .65); }
.footer-links li { margin-bottom: 10px; }
.footer-links a { font-size: 14px; color: rgba(255, 255, 255, .78); }
.footer-links a:hover { color: var(--accent); }
.footer-contact li { display: flex; gap: 10px; font-size: 14px; margin-bottom: 12px; align-items: flex-start; }
.footer-contact svg { flex: none; width: 18px; height: 18px; margin-top: 3px; stroke: var(--accent); fill: none; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.footer-contact a:hover { color: #fff; }
.footer-qr { display: flex; align-items: flex-start; gap: 16px; }
.footer-qr img { width: 96px; height: 96px; border-radius: 8px; border: 1px solid rgba(255, 255, 255, .2); }
.footer-qr p { font-size: 13px; color: rgba(255, 255, 255, .65); }

.footer-bottom { border-top: 1px solid rgba(255, 255, 255, .12); padding: 18px 0; text-align: center; font-size: 13px; color: rgba(255, 255, 255, .5); }
.footer-bottom a { color: rgba(255, 255, 255, .75); }
.footer-bottom a:hover { color: var(--accent); }

/* ---------- 返回顶部 ---------- */
.back-top {
  position: fixed; right: 22px; bottom: 26px; z-index: 90;
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--primary); color: #fff; font-size: 18px;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 6px 18px rgba(11, 74, 143, .3);
  opacity: 0; visibility: hidden; transform: translateY(12px);
  transition: opacity .25s ease, transform .25s ease, visibility .25s ease;
}
.back-top.show { opacity: 1; visibility: visible; transform: translateY(0); }
.back-top:hover { background: var(--primary-600); }

/* ---------- 滚动显现动画（无 JS 时内容默认可见） ---------- */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .7s ease, transform .7s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .cards-grid { grid-template-columns: repeat(2, 1fr); }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-cards { grid-template-columns: repeat(2, 1fr); }
  .steps-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .section { padding: 60px 0; }

  /* 导航折叠 */
  .nav {
    position: absolute; top: 76px; left: 0; right: 0;
    flex-direction: column; gap: 4px; padding: 14px 20px 20px;
    background: var(--white); border-bottom: 1px solid var(--border);
    box-shadow: 0 18px 30px rgba(11, 74, 143, .10);
    display: none;
  }
  .nav.open { display: flex; }
  .nav-toggle { display: flex; }

  .intro, .about-grid { grid-template-columns: 1fr; gap: 34px; }
  .contact-split { grid-template-columns: 1fr; gap: 30px; }
  .values-grid { grid-template-columns: 1fr; }

  .footer-grid { grid-template-columns: 1fr; gap: 32px; padding: 46px 0 34px; }
  .hero-arrow { display: none; }   /* 移动端用小圆点切换即可 */
  .slide-actions .btn { padding: 12px 22px; font-size: 14px; }
}

@media (max-width: 520px) {
  .cards-grid, .features-grid, .contact-cards, .steps-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .logo-text strong { font-size: 17px; }
}

/* 尊重系统“减少动态效果”设置 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .slide, .slide-bg { transition: none; }
}