/* ===== 变量 ===== */
:root {
  --c-primary: #1a2a4a;
  --c-primary-light: #2d4a7c;
  --c-gold: #b8860b;
  --c-gold-light: #d4a843;
  --c-bg: #f7f8fa;
  --c-white: #ffffff;
  --c-text: #2c3e50;
  --c-text-light: #5a6a7a;
  --c-border: #e2e8f0;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
  --shadow-md: 0 8px 30px rgba(0,0,0,0.1);
  --radius: 8px;
  --max-w: 1200px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

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

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== 导航 ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--c-white);
  box-shadow: var(--shadow-sm);
  transition: background 0.3s;
}

.header.scrolled {
  background: rgba(255,255,255,0.97);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-md);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-img {
  height: 44px;
  width: auto;
  object-fit: contain;
}

.logo-text h1 {
  font-size: 18px;
  color: var(--c-primary);
  font-weight: 700;
  line-height: 1.2;
}

.logo-text p {
  font-size: 10px;
  color: var(--c-text-light);
  letter-spacing: 1.5px;
}

.nav {
  display: flex;
  gap: 32px;
}

.nav a {
  text-decoration: none;
  color: var(--c-text);
  font-size: 15px;
  position: relative;
  transition: color 0.25s;
}

.nav a::after {
  content: "";
  position: absolute;
  bottom: -6px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--c-gold);
  transition: width 0.3s;
}

.nav a:hover {
  color: var(--c-primary);
}

.nav a:hover::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  flex-direction: column;
  gap: 5px;
  padding: 4px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--c-primary);
  transition: 0.3s;
}

/* ===== Hero ===== */
.hero {
  margin-top: 72px;
  min-height: calc(100vh - 72px);
  display: flex;
  padding: 60px 0;
  background: linear-gradient(135deg, var(--c-primary) 0%, var(--c-primary-light) 100%);
  color: var(--c-white);
  position: relative;
  overflow: hidden;
}

.hero > .container {
  display: flex;
  flex-direction: column;
  justify-content: center;
  width: 100%;
}

.hero::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 700px;
  height: 700px;
  background: radial-gradient(circle, rgba(184,134,11,0.15) 0%, transparent 70%);
  pointer-events: none;
}

.hero-content {
  max-width: 680px;
  position: relative;
  z-index: 1;
}

.hero-sub {
  font-size: 14px;
  color: var(--c-gold-light);
  letter-spacing: 3px;
  margin-bottom: 16px;
}

.hero h2 {
  font-size: 44px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 20px;
}

.hero-desc {
  font-size: 17px;
  line-height: 1.9;
  color: rgba(255,255,255,0.85);
  margin-bottom: 36px;
}

.hero-btns {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 12px 32px;
  font-size: 15px;
  text-decoration: none;
  border-radius: 4px;
  transition: all 0.25s;
  cursor: pointer;
}

.btn-primary {
  background: var(--c-gold);
  color: var(--c-white);
}

.btn-primary:hover {
  background: var(--c-gold-light);
  transform: translateY(-2px);
}

.btn-outline {
  border: 1px solid rgba(255,255,255,0.5);
  color: var(--c-white);
}

.btn-outline:hover {
  background: rgba(255,255,255,0.1);
  border-color: var(--c-white);
}

.btn-gold {
  background: var(--c-gold);
  color: var(--c-white);
  width: 100%;
  border: none;
}

.btn-gold:hover {
  background: var(--c-gold-light);
}

.hero-stats {
  display: flex;
  gap: 48px;
  margin-top: 56px;
  padding-top: 36px;
  border-top: 1px solid rgba(255,255,255,0.15);
  position: relative;
  z-index: 1;
  flex-wrap: wrap;
}

.stat-num {
  display: block;
  font-size: 32px;
  font-weight: 700;
  color: var(--c-gold-light);
  margin-bottom: 4px;
}

.stat-label {
  font-size: 13px;
  color: rgba(255,255,255,0.6);
  letter-spacing: 1px;
}

.stat-num {
  display: block;
  font-size: 32px;
  font-weight: 700;
  color: var(--c-gold-light);
  margin-bottom: 4px;
}

.stat-label {
  font-size: 13px;
  color: rgba(255,255,255,0.6);
  letter-spacing: 1px;
}

/* ===== 通用 section ===== */
.section {
  padding: 80px 0;
}

.section-alt {
  background: var(--c-white);
}

.section-dark {
  background: var(--c-primary);
  color: var(--c-white);
}

.section-head {
  text-align: center;
  margin-bottom: 56px;
}

.section-head .section-tag {
  display: inline-block;
  font-size: 12px;
  letter-spacing: 3px;
  color: var(--c-gold);
  text-transform: uppercase;
  margin-bottom: 12px;
}

.section-head h3 {
  font-size: 32px;
  color: var(--c-primary);
  font-weight: 700;
}

.section-head.light h3 {
  color: var(--c-white);
}

.section-head .divider {
  width: 56px;
  height: 3px;
  background: var(--c-gold);
  margin: 16px auto 0;
  border-radius: 2px;
}

/* ===== 关于 ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 56px;
  align-items: start;
}

.lead {
  font-size: 18px;
  font-weight: 500;
  color: var(--c-primary);
  margin-bottom: 20px;
  line-height: 1.9;
}

.about-text p {
  margin-bottom: 16px;
  font-size: 15px;
  line-height: 1.9;
  color: var(--c-text);
}

.about-info {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.info-item {
  padding: 16px;
  background: var(--c-white);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
}

.info-label {
  display: block;
  font-size: 12px;
  color: var(--c-gold);
  letter-spacing: 1px;
  margin-bottom: 6px;
  text-transform: uppercase;
}

.info-item p {
  font-size: 14px;
  color: var(--c-text);
  line-height: 1.5;
}

/* ===== 业务 ===== */
.services-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

/* ===== 优势 ===== */
.strengths-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

/* ===== 联系 ===== */
.contact-wrap {
  max-width: 560px;
  margin: 0 auto;
}

.contact-intro {
  text-align: center;
  font-size: 16px;
  color: rgba(255,255,255,0.8);
  line-height: 1.9;
  margin-bottom: 32px;
}

.service-card {
  background: var(--c-bg);
  border-radius: var(--radius);
  padding: 28px 24px;
  border: 1px solid transparent;
  transition: all 0.3s;
}

.service-card:hover {
  border-color: var(--c-gold);
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
  background: var(--c-white);
}

.service-icon {
  width: 48px;
  height: 48px;
  background: var(--c-primary);
  color: var(--c-gold-light);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
}

.service-icon svg {
  width: 24px;
  height: 24px;
}

.service-card h4 {
  font-size: 17px;
  color: var(--c-primary);
  margin-bottom: 10px;
}

.service-card p {
  font-size: 14px;
  color: var(--c-text-light);
  line-height: 1.7;
}

/* ===== 优势 ===== */
.strengths-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.strength-item {
  padding: 32px 24px;
  background: var(--c-white);
  border-radius: var(--radius);
  border: 1px solid var(--c-border);
  text-align: center;
  transition: all 0.3s;
}

.strength-item:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
}

.strength-num {
  font-size: 36px;
  font-weight: 700;
  color: var(--c-gold);
  opacity: 0.3;
  margin-bottom: 12px;
  line-height: 1;
}

.strength-item h4 {
  font-size: 18px;
  color: var(--c-primary);
  margin-bottom: 10px;
}

.strength-item p {
  font-size: 14px;
  color: var(--c-text-light);
  line-height: 1.7;
}

/* ===== 联系 ===== */
.contact-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.form-msg {
  font-size: 14px;
  text-align: center;
  min-height: 20px;
  line-height: 1.6;
}

.form-msg.success {
  color: var(--c-gold-light);
}

.form-msg.error {
  color: #ff8a8a;
}

.contact-form input,
.contact-form textarea {
  padding: 14px 16px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 4px;
  color: var(--c-white);
  font-size: 15px;
  font-family: inherit;
  transition: border-color 0.25s;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder {
  color: rgba(255,255,255,0.4);
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--c-gold);
}

/* ===== 页脚 ===== */
.footer {
  background: #0f1c33;
  color: rgba(255,255,255,0.6);
  padding: 48px 0 0;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 40px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}

.footer-logo .logo-img {
  height: 38px;
  width: auto;
  object-fit: contain;
}

.footer-logo strong {
  font-size: 16px;
  color: var(--c-white);
  display: block;
}

.footer-logo small {
  font-size: 10px;
  letter-spacing: 1px;
  color: rgba(255,255,255,0.4);
}

.footer-desc {
  font-size: 13px;
  letter-spacing: 2px;
}

.footer-col h5 {
  font-size: 14px;
  color: var(--c-white);
  margin-bottom: 16px;
  letter-spacing: 1px;
}

.footer-col a,
.footer-col p {
  display: block;
  font-size: 14px;
  text-decoration: none;
  margin-bottom: 10px;
  transition: color 0.2s;
}

.footer-col a {
  color: rgba(255,255,255,0.55);
}

.footer-col a:hover {
  color: var(--c-gold-light);
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 20px 24px;
  text-align: center;
}

.footer-bottom p {
  font-size: 12px;
  color: rgba(255,255,255,0.35);
  margin-bottom: 6px;
}

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
  .services-grid,
  .strengths-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

@media (max-width: 768px) {
  .nav {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--c-white);
    flex-direction: column;
    padding: 24px;
    gap: 20px;
    box-shadow: var(--shadow-md);
    transform: translateY(-120%);
    transition: transform 0.35s;
  }

  .nav.open {
    transform: translateY(0);
  }

  .nav-toggle {
    display: flex;
  }

  .hero {
    padding: 40px 0;
  }

  .hero h2 {
    font-size: 30px;
  }

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

  .hero-stats {
    gap: 24px;
    margin-top: 36px;
    padding-top: 24px;
    flex-wrap: nowrap;
    overflow-x: auto;
  }

  .stat-num {
    font-size: 24px;
  }

  .section {
    padding: 56px 0;
  }

  .section-head h3 {
    font-size: 26px;
  }

  .services-grid,
  .strengths-grid {
    grid-template-columns: 1fr;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .about-info {
    grid-template-columns: 1fr;
  }
}

/* ===== 动画 ===== */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}

.hero-content,
.hero-stats {
  animation: fadeIn 0.8s ease-out;
}