/* =============================================
   湖北仟诚信息技术咨询有限公司 - 企业官网样式
   配色：深炭灰 + 暖金 + 纯白，无渐变
   ============================================= */

:root {
  --color-black: #0a0a0a;
  --color-dark: #1a1a1a;
  --color-charcoal: #2a2a2a;
  --color-gray-dark: #444444;
  --color-gray: #888888;
  --color-gray-light: #c8c8c8;
  --color-border: #e0e0e0;
  --color-bg: #fafafa;
  --color-white: #ffffff;
  --color-accent: #b08d57;
  --color-accent-dark: #96763e;

  --font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI',
    'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;

  --container-width: 1200px;
  --section-padding: 120px 0;
  --transition: 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-family);
  color: var(--color-dark);
  background: var(--color-white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--transition);
}

ul {
  list-style: none;
}

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

/* ======================== 按钮 ======================== */

.btn {
  display: inline-block;
  padding: 14px 40px;
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 1px;
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font-family);
}

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

.btn-primary:hover {
  background: var(--color-accent-dark);
}

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

.btn-outline:hover {
  background: var(--color-white);
  color: var(--color-dark);
  border-color: var(--color-white);
}

.btn-full {
  width: 100%;
}

/* ======================== 导航 ======================== */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 20px 0;
  transition: all 0.4s ease;
}

.navbar.scrolled {
  background: rgba(10, 10, 10, 0.95);
  padding: 12px 0;
  backdrop-filter: blur(10px);
}

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

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: var(--color-accent);
  color: var(--color-white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  font-weight: 700;
}

.logo-text {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-white);
  letter-spacing: 2px;
}

.nav-links {
  display: flex;
  gap: 36px;
}

.nav-links a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
  letter-spacing: 1px;
  position: relative;
  padding: 4px 0;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--color-accent);
  transition: width var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--color-white);
}

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

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

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-white);
  transition: all var(--transition);
}

/* ======================== 首屏 ======================== */

.hero {
  position: relative;
  height: 100vh;
  min-height: 700px;
  display: flex;
  align-items: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: var(--color-black);
}

.hero-bg::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 50%, rgba(176, 141, 87, 0.08) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(176, 141, 87, 0.05) 0%, transparent 40%);
}

.hero-bg::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: rgba(255, 255, 255, 0.08);
}

.hero-content {
  position: relative;
  z-index: 2;
}

.hero-sub {
  color: var(--color-accent);
  font-size: 0.8rem;
  letter-spacing: 6px;
  margin-bottom: 28px;
  font-weight: 400;
}

.hero-title {
  color: var(--color-white);
  font-size: 3.6rem;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 28px;
  letter-spacing: 2px;
}

.hero-desc {
  color: rgba(255, 255, 255, 0.55);
  font-size: 1.05rem;
  max-width: 580px;
  margin-bottom: 48px;
  line-height: 1.8;
}

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

.hero-scroll {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  z-index: 2;
}

.hero-scroll span {
  color: rgba(255, 255, 255, 0.35);
  font-size: 0.7rem;
  letter-spacing: 3px;
  writing-mode: vertical-lr;
}

.scroll-line {
  width: 1px;
  height: 40px;
  background: rgba(255, 255, 255, 0.15);
  position: relative;
  overflow: hidden;
}

.scroll-line::after {
  content: '';
  position: absolute;
  top: -100%;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--color-accent);
  animation: scrollDown 2s ease-in-out infinite;
}

@keyframes scrollDown {
  0% { top: -100%; }
  100% { top: 100%; }
}

/* ======================== 通用版块 ======================== */

.section {
  padding: var(--section-padding);
}

.section-header {
  text-align: center;
  margin-bottom: 72px;
}

.section-tag {
  display: inline-block;
  font-size: 0.75rem;
  letter-spacing: 4px;
  color: var(--color-accent);
  margin-bottom: 16px;
  font-weight: 500;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--color-dark);
  letter-spacing: 3px;
  margin-bottom: 20px;
}

.section-line {
  width: 48px;
  height: 2px;
  background: var(--color-accent);
  margin: 0 auto;
}

/* ======================== 关于我们 ======================== */

.about {
  background: var(--color-bg);
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
}

.about-text p {
  color: var(--color-gray-dark);
  margin-bottom: 20px;
  font-size: 0.95rem;
}

.about-lead {
  font-size: 1.1rem !important;
  color: var(--color-dark) !important;
  font-weight: 500;
  line-height: 1.9;
}

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

.stat-card {
  background: var(--color-white);
  padding: 36px 28px;
  text-align: center;
  border: 1px solid var(--color-border);
  transition: all var(--transition);
  position: relative;
}

.stat-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--color-accent);
  transform: scaleX(0);
  transition: transform var(--transition);
}

.stat-card:hover::before {
  transform: scaleX(1);
}

.stat-card:hover {
  border-color: var(--color-accent);
}

.stat-number {
  font-size: 2.8rem;
  font-weight: 700;
  color: var(--color-dark);
  display: inline;
  line-height: 1;
}

.stat-unit {
  font-size: 1.4rem;
  color: var(--color-accent);
  font-weight: 500;
  display: inline;
  margin-left: 2px;
}

.stat-label {
  margin-top: 10px;
  font-size: 0.85rem;
  color: var(--color-gray);
  letter-spacing: 1px;
}

/* ======================== 服务领域 ======================== */

.services {
  background: var(--color-white);
}

.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.service-card {
  padding: 48px 36px;
  border: 1px solid var(--color-border);
  transition: all 0.4s ease;
  position: relative;
  background: var(--color-white);
}

.service-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--color-accent);
  transform: scaleX(0);
  transition: transform 0.4s ease;
  transform-origin: left;
}

.service-card:hover {
  border-color: var(--color-charcoal);
  transform: translateY(-4px);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.06);
}

.service-card:hover::after {
  transform: scaleX(1);
}

.service-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 28px;
  color: var(--color-accent);
}

.service-icon svg {
  width: 100%;
  height: 100%;
}

.service-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--color-dark);
  letter-spacing: 1px;
}

.service-card p {
  color: var(--color-gray);
  font-size: 0.9rem;
  line-height: 1.8;
}

/* ======================== 核心优势 ======================== */

.advantages {
  background: var(--color-dark);
}

.advantages .section-title {
  color: var(--color-white);
}

.advantages-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 40px;
}

.advantage-item {
  text-align: center;
  padding: 20px;
}

.advantage-num {
  font-size: 3.5rem;
  font-weight: 700;
  color: var(--color-accent);
  opacity: 0.4;
  margin-bottom: 20px;
  line-height: 1;
}

.advantage-item h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--color-white);
  margin-bottom: 16px;
  letter-spacing: 2px;
}

.advantage-item p {
  font-size: 0.88rem;
  color: rgba(255, 255, 255, 0.45);
  line-height: 1.8;
}

/* ======================== 合作流程 ======================== */

.process {
  background: var(--color-bg);
}

.process-steps {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0;
}

.process-step {
  text-align: center;
  flex: 1;
  max-width: 240px;
}

.step-number {
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: 20px;
  line-height: 1;
}

.step-content h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--color-dark);
  margin-bottom: 8px;
  letter-spacing: 1px;
}

.step-content p {
  font-size: 0.85rem;
  color: var(--color-gray);
}

.process-connector {
  width: 60px;
  height: 1px;
  background: var(--color-border);
  flex-shrink: 0;
}

/* ======================== 联系我们 ======================== */

.contact {
  background: var(--color-white);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 36px;
  padding-top: 12px;
}

.contact-item {
  display: flex;
  gap: 20px;
  align-items: flex-start;
}

.contact-icon {
  width: 44px;
  height: 44px;
  flex-shrink: 0;
  color: var(--color-accent);
  padding: 8px;
  border: 1px solid var(--color-border);
}

.contact-icon svg {
  width: 100%;
  height: 100%;
}

.contact-item h4 {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-dark);
  margin-bottom: 4px;
  letter-spacing: 1px;
}

.contact-item p {
  font-size: 0.88rem;
  color: var(--color-gray);
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 16px 20px;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  font-size: 0.9rem;
  color: var(--color-dark);
  font-family: var(--font-family);
  transition: border-color var(--transition);
  outline: none;
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--color-accent);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

.contact-form .btn-primary {
  margin-top: 4px;
  padding: 16px;
  font-size: 0.95rem;
  letter-spacing: 3px;
}

/* ======================== 底部 ======================== */

.footer {
  background: var(--color-black);
  padding: 64px 0 0;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.footer-brand .logo {
  margin-bottom: 16px;
}

.footer-slogan {
  color: rgba(255, 255, 255, 0.35);
  font-size: 0.85rem;
  letter-spacing: 2px;
}

.footer-nav {
  display: flex;
  gap: 80px;
}

.footer-col h4 {
  color: var(--color-white);
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 20px;
  letter-spacing: 1px;
}

.footer-col a {
  display: block;
  color: rgba(255, 255, 255, 0.4);
  font-size: 0.85rem;
  margin-bottom: 12px;
  transition: color var(--transition);
}

.footer-col a:hover {
  color: var(--color-accent);
}

.footer-bottom {
  padding: 28px 0;
  text-align: center;
}

.footer-bottom p {
  color: #ffffff;
  font-size: 0.8rem;
  letter-spacing: 1px;
}

.footer-beian {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  margin-top: 12px;
}

.beian-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  color: #ffffff !important;
  font-size: 0.8rem;
  letter-spacing: 0.5px;
  transition: color var(--transition);
}

.beian-link:hover {
  color: rgba(255, 255, 255, 0.7) !important;
}

.beian-icon {
  width: 14px;
  height: 14px;
  object-fit: contain;
  flex-shrink: 0;
}

/* ======================== 回到顶部 ======================== */

.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  background: var(--color-dark);
  border: 1px solid var(--color-charcoal);
  color: var(--color-white);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition);
  z-index: 999;
}

.back-to-top svg {
  width: 18px;
  height: 18px;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background: var(--color-accent);
  border-color: var(--color-accent);
}

/* ======================== 动画 ======================== */

.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ======================== 响应式 ======================== */

@media (max-width: 1024px) {
  .hero-title {
    font-size: 2.8rem;
  }

  .about-grid {
    gap: 48px;
  }

  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .advantages-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
  }

  .process-steps {
    flex-wrap: wrap;
    gap: 24px;
  }

  .process-connector {
    display: none;
  }

  .process-step {
    flex: 0 0 calc(50% - 12px);
    max-width: none;
  }

  .footer-nav {
    gap: 48px;
  }
}

@media (max-width: 768px) {
  :root {
    --section-padding: 80px 0;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: var(--color-black);
    flex-direction: column;
    padding: 100px 40px;
    gap: 24px;
    transition: right 0.4s ease;
  }

  .nav-links.open {
    right: 0;
  }

  .nav-toggle {
    display: flex;
    z-index: 1001;
  }

  .nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }

  .nav-toggle.active span:nth-child(2) {
    opacity: 0;
  }

  .nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  .hero {
    min-height: 600px;
  }

  .hero-title {
    font-size: 2rem;
  }

  .hero-sub {
    font-size: 0.7rem;
    letter-spacing: 3px;
  }

  .hero-desc {
    font-size: 0.9rem;
  }

  .hero-actions {
    flex-direction: column;
    gap: 12px;
  }

  .hero-actions .btn {
    text-align: center;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

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

  .service-card {
    padding: 36px 28px;
  }

  .advantages-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .advantage-item {
    padding: 16px 0;
  }

  .contact-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .footer-top {
    flex-direction: column;
    gap: 40px;
  }

  .footer-nav {
    gap: 40px;
  }

  .section-title {
    font-size: 1.7rem;
  }
}

@media (max-width: 480px) {
  .about-stats {
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }

  .stat-card {
    padding: 24px 16px;
  }

  .stat-number {
    font-size: 2rem;
  }

  .hero-title {
    font-size: 1.7rem;
  }

  .process-step {
    flex: 0 0 100%;
  }
}