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

html,
body {
  margin: 0;
  padding: 0;
  min-height: 100dvh;
}

@supports not (min-height: 100dvh) {
  html,
  body {
    min-height: 100vh;
  }
}

body {
  display: flex;
  flex-direction: column;

  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei",
    "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: #2c3e50;
  background: #ffffff;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: #1a4d8f;
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: #0d2f5a;
}

img {
  max-width: 100%;
  display: block;
}

ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

h1, h2, h3 {
  font-weight: 600;
  line-height: 1.3;
  color: #1a2a3a;
}

p {
  margin: 0 0 1em;
}

.site-main {
  flex: 1 1 auto;
  min-height: 0;
  display: block;
}

.site-main--center {
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ===== 通用容器 ===== */
.container {
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ===== 顶部导航 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: #ffffff;
  border-bottom: 1px solid #eaecef;
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #1a2a3a;
  font-weight: 600;
  font-size: 18px;
}

.brand-logo {
  height: 32px;
  width: auto;
  display: block;
}

.brand-name {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 220px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-link {
  position: relative;
  color: #4a5b6f;
  font-size: 15px;
  padding: 6px 0;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 2px;
  background: #1a4d8f;
  transition: width 0.2s ease;
}

.nav-link:hover,
.nav-link.active {
  color: #1a4d8f;
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 28px;
  height: 22px;
  padding: 0;
  border: none;
  background: transparent;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: #2c3e50;
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

/* ===== Hero 区 ===== */
.hero {
  background: linear-gradient(135deg, #1a4d8f 0%, #2c6cb8 100%);
  color: #ffffff;
  padding: 96px 0;
  text-align: center;
}

.hero-title {
  font-size: 36px;
  margin: 0 0 16px;
  color: #ffffff;
}

.hero-subtitle {
  font-size: 18px;
  margin: 0 0 32px;
  color: rgba(255, 255, 255, 0.92);
}

/* ===== 通用按钮 ===== */
.btn {
  display: inline-block;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 500;
  border-radius: 4px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.btn-primary {
  background: #ffffff;
  color: #1a4d8f;
  border-color: #ffffff;
}

.btn-primary:hover {
  background: #f0f4fa;
  color: #0d2f5a;
}

.btn-ghost {
  background: transparent;
  color: #1a4d8f;
  border-color: #1a4d8f;
  margin-top: 12px;
}

.btn-ghost:hover {
  background: #1a4d8f;
  color: #ffffff;
}

/* ===== 页面 banner（非首页）===== */
.page-banner {
  background: #f5f7fa;
  padding: 64px 0;
  text-align: center;
  border-bottom: 1px solid #eaecef;
}

.page-banner h1 {
  font-size: 30px;
  margin: 0 0 8px;
}

.page-banner p {
  margin: 0;
  color: #6b7a8a;
}

/* ===== 章节 ===== */
.section {
  padding: 64px 0;
}

.section-alt {
  background: #f8fafc;
}

.section-title {
  font-size: 26px;
  text-align: center;
  margin: 0 0 32px;
  position: relative;
  padding-bottom: 14px;
}

.section-title::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 0;
  transform: translateX(-50%);
  width: 40px;
  height: 3px;
  background: #1a4d8f;
  border-radius: 2px;
}

.section-body {
  max-width: 760px;
  margin: 0 auto;
  color: #4a5b6f;
}

/* ===== 服务范围 ===== */
.service-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.service-item {
  background: #ffffff;
  border: 1px solid #eaecef;
  border-radius: 6px;
  padding: 24px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.service-item:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(26, 77, 143, 0.08);
}

.service-item h3 {
  font-size: 18px;
  margin: 0 0 10px;
  color: #1a4d8f;
}

.service-item p {
  margin: 0;
  color: #4a5b6f;
  font-size: 14px;
  line-height: 1.65;
}

/* ===== 能力清单 ===== */
.feature-list {
  max-width: 760px;
  margin: 0 auto;
  color: #4a5b6f;
}

.feature-list li {
  padding: 10px 0 10px 24px;
  position: relative;
  border-bottom: 1px dashed #eaecef;
}

.feature-list li:last-child {
  border-bottom: none;
}

.feature-list li::before {
  content: "▸";
  position: absolute;
  left: 0;
  top: 10px;
  color: #1a4d8f;
  font-weight: 700;
}

/* ===== 首页联系方式预览 ===== */
.contact-preview {
  max-width: 600px;
  margin: 0 auto;
  text-align: center;
  color: #4a5b6f;
}

.contact-preview p {
  margin: 0 0 10px;
}

/* ===== 联系方式页卡片 ===== */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 20px;
  max-width: 900px;
  margin: 0 auto;
}

.contact-card {
  background: #ffffff;
  border: 1px solid #eaecef;
  border-radius: 6px;
  padding: 24px;
  text-align: center;
}

.contact-card h3 {
  font-size: 16px;
  margin: 0 0 10px;
  color: #1a4d8f;
}

.contact-card p {
  margin: 0;
  color: #4a5b6f;
  word-break: break-all;
}

/* ===== 底部 ===== */
.site-footer {
  flex-shrink: 0;
  background: #1a2a3a;
  color: #aab4c0;
  padding: 28px 0;
  text-align: center;
  font-size: 13px;
}

.site-footer p {
  margin: 4px 0;
}

.footer-copy {
  color: #cfd6df;
}

.footer-records a {
  color: #aab4c0;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin: 0 6px;
}

.footer-records a:hover {
  color: #ffffff;
}

.record-sep {
  color: #4a5b6f;
  margin: 0 4px;
}

.beian-icon {
  display: inline-block;
  width: 16px;
  height: 16px;
  vertical-align: middle;
}

/* ===== 响应式 ===== */
@media (max-width: 720px) {
  .nav-toggle {
    display: flex;
  }

  .nav {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: #ffffff;
    border-bottom: 1px solid #eaecef;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.25s ease;
  }

  .nav.is-open {
    max-height: 280px;
  }

  .nav-link {
    width: 100%;
    padding: 14px 20px;
    border-top: 1px solid #f0f2f5;
  }

  .nav-link::after {
    display: none;
  }

  .hero {
    padding: 64px 0;
  }

  .hero-title {
    font-size: 26px;
  }

  .hero-subtitle {
    font-size: 15px;
  }

  .page-banner {
    padding: 48px 0;
  }

  .page-banner h1 {
    font-size: 24px;
  }

  .section {
    padding: 48px 0;
  }

  .section-title {
    font-size: 22px;
  }
}