/* 基础变量与重置 */
:root {
  --primary: #ff6600;
  --primary-hover: #e55a00;
  --primary-light: rgba(255, 102, 0, 0.15);
  --dark: #1a1a2e;
  --light: #f8f9fa;
  --gray: #6c757d;
  --text: #333;
  --bg: #fff;
  --card-bg: #fff;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  --shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.12);
  --radius: 12px;
  --radius-sm: 8px;
  --radius-lg: 20px;
  --transition: 0.3s ease;
  --transition-slow: 0.5s ease;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --max-width: 1200px;
  --header-height: 70px;
  --glass-bg: rgba(255, 255, 255, 0.15);
  --glass-border: rgba(255, 255, 255, 0.2);
  --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  --gradient-hero: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
  --gradient-card: linear-gradient(145deg, #ffffff, #f0f0f0);
  --num-color: #ff6600;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  overflow-x: hidden;
  transition: background var(--transition), color var(--transition);
}

/* 暗色模式 */
body.dark {
  --bg: #121212;
  --text: #e0e0e0;
  --card-bg: #1e1e1e;
  --light: #2a2a2a;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
  --shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.5);
  --gradient-card: linear-gradient(145deg, #1e1e1e, #252525);
  --glass-bg: rgba(30, 30, 30, 0.6);
  --glass-border: rgba(255, 255, 255, 0.08);
}

/* 链接 */
a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition);
}

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

/* 标题 */
h1, h2, h3, h4 {
  font-weight: 700;
  line-height: 1.3;
}

h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

h2 {
  font-size: 2rem;
  margin: 2.5rem 0 1.5rem;
  position: relative;
  display: inline-block;
}

h2::after {
  content: '';
  display: block;
  width: 60px;
  height: 4px;
  background: var(--primary);
  margin-top: 8px;
  border-radius: 2px;
  transition: width var(--transition);
}

h2:hover::after {
  width: 100px;
}

h3 {
  font-size: 1.4rem;
  margin-bottom: 0.8rem;
}

p {
  margin-bottom: 1rem;
}

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

/* 按钮 */
.btn {
  display: inline-block;
  padding: 12px 32px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 50px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  text-align: center;
  position: relative;
  overflow: hidden;
  z-index: 1;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
  transition: left 0.6s;
  z-index: -1;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(255, 102, 0, 0.3);
}

.btn:hover::before {
  left: 100%;
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--primary);
  color: var(--primary);
}

.btn-outline:hover {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 8px 25px rgba(255, 102, 0, 0.3);
}

/* 卡片 */
.card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 30px;
  transition: all var(--transition);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid transparent;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-hover);
  border-color: var(--primary-light);
}

/* 网格 */
.grid {
  display: grid;
  gap: 30px;
}

.grid-2 {
  grid-template-columns: 1fr 1fr;
}

.grid-3 {
  grid-template-columns: 1fr 1fr 1fr;
}

.grid-4 {
  grid-template-columns: 1fr 1fr 1fr 1fr;
}

.text-center {
  text-align: center;
}

.mt-2 {
  margin-top: 2rem;
}

.mb-2 {
  margin-bottom: 2rem;
}

.section {
  padding: 80px 0;
}

/* 响应式 */
@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }
  h2 {
    font-size: 1.6rem;
  }
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
  .section {
    padding: 50px 0;
  }
}

/* ===== 头部 ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(26, 26, 46, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  padding: 15px 0;
  transition: background var(--transition), box-shadow var(--transition);
}

.header.scrolled {
  background: rgba(26, 26, 46, 0.98);
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

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

.logo {
  font-size: 1.8rem;
  font-weight: 800;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 10px;
  transition: transform var(--transition);
}

.logo:hover {
  transform: scale(1.02);
}

.logo span {
  color: var(--primary);
}

.nav {
  display: flex;
  gap: 25px;
  list-style: none;
}

.nav a {
  color: #fff;
  font-weight: 500;
  transition: color var(--transition);
  position: relative;
  padding: 5px 0;
}

.nav a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width var(--transition);
}

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

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

.menu-toggle {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 1.5rem;
  cursor: pointer;
  padding: 5px;
  transition: transform var(--transition);
}

.menu-toggle:hover {
  transform: rotate(90deg);
}

@media (max-width: 768px) {
  .nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: rgba(26, 26, 46, 0.98);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    flex-direction: column;
    padding: 20px;
    gap: 15px;
    text-align: center;
    animation: slideDown 0.3s ease;
  }

  .nav.open {
    display: flex;
  }

  .menu-toggle {
    display: block;
  }
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ===== Hero ===== */
.hero {
  background: var(--gradient-hero);
  color: #fff;
  padding: 140px 0 100px;
  position: relative;
  overflow: hidden;
  min-height: 70vh;
  display: flex;
  align-items: center;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(255, 102, 0, 0.15) 0%, transparent 70%);
  border-radius: 50%;
  animation: pulseGlow 4s ease-in-out infinite;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(255, 102, 0, 0.1) 0%, transparent 70%);
  border-radius: 50%;
  animation: pulseGlow 5s ease-in-out infinite reverse;
}

@keyframes pulseGlow {
  0%, 100% {
    transform: scale(1);
    opacity: 0.6;
  }
  50% {
    transform: scale(1.1);
    opacity: 1;
  }
}

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

.hero h1 {
  font-size: 3.2rem;
  max-width: 800px;
  margin-bottom: 1.5rem;
  line-height: 1.2;
  animation: fadeInUp 0.8s ease;
}

.hero p {
  font-size: 1.2rem;
  max-width: 600px;
  margin-bottom: 2rem;
  color: rgba(255, 255, 255, 0.8);
  animation: fadeInUp 0.8s ease 0.2s both;
}

.hero .btn-group {
  display: flex;
  gap: 15px;
  flex-wrap: wrap;
  animation: fadeInUp 0.8s ease 0.4s both;
}

.hero .btn {
  font-size: 1.1rem;
  padding: 15px 40px;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 768px) {
  .hero {
    padding: 120px 0 70px;
  }
  .hero h1 {
    font-size: 2.2rem;
  }
  .hero p {
    font-size: 1rem;
  }
}

/* ===== About ===== */
.about {
  background: var(--light);
  position: relative;
}

.about .grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 50px;
  align-items: center;
}

@media (max-width: 768px) {
  .about .grid {
    grid-template-columns: 1fr;
  }
}

.company-info {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-top: 30px;
}

.company-info .item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px;
  background: var(--card-bg);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow);
  transition: all var(--transition);
}

.company-info .item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
}

.company-info .item .icon {
  font-size: 1.5rem;
}

/* ===== Products ===== */
.products .card {
  padding: 25px;
  background: var(--gradient-card);
  border: 1px solid rgba(255, 102, 0, 0.05);
}

.products .card h3 {
  color: var(--primary);
}

.products .card .price {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--dark);
  margin: 10px 0;
}

body.dark .products .card .price {
  color: #fff;
}

/* ===== Services ===== */
.services .grid {
  grid-template-columns: 1fr 1fr 1fr;
}

.services .card {
  text-align: center;
  background: var(--gradient-card);
}

.services .card .icon {
  font-size: 3rem;
  margin-bottom: 15px;
  color: var(--primary);
  transition: transform var(--transition);
}

.services .card:hover .icon {
  transform: scale(1.2) rotate(5deg);
}

/* ===== Advantages ===== */
.advantages .grid {
  grid-template-columns: 1fr 1fr 1fr 1fr;
}

.advantages .card {
  text-align: center;
  padding: 20px;
  background: var(--gradient-card);
}

.advantages .card .num {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--num-color);
  margin-bottom: 5px;
  transition: all var(--transition);
}

.advantages .card:hover .num {
  transform: scale(1.1);
}

/* ===== Testimonials ===== */
.testimonials .grid {
  grid-template-columns: 1fr 1fr 1fr;
}

.testimonials .card {
  position: relative;
  padding-top: 40px;
}

.testimonials .card::before {
  content: '\201C';
  font-size: 4rem;
  color: var(--primary);
  position: absolute;
  top: 5px;
  left: 20px;
  opacity: 0.3;
  transition: opacity var(--transition);
}

.testimonials .card:hover::before {
  opacity: 0.6;
}

.testimonials .card .author {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 15px;
}

.testimonials .card .author img {
  width: 45px;
  height: 45px;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--primary-light);
  transition: border-color var(--transition);
}

.testimonials .card:hover .author img {
  border-color: var(--primary);
}

/* ===== Insights ===== */
.insights .grid {
  grid-template-columns: 1fr 1fr 1fr;
}

.insights .card {
  position: relative;
  overflow: hidden;
}

.insights .card .date {
  color: var(--gray);
  font-size: 0.9rem;
  margin-bottom: 10px;
}

.insights .card .tag {
  display: inline-block;
  padding: 4px 12px;
  background: var(--primary-light);
  color: var(--primary);
  border-radius: 20px;
  font-size: 0.85rem;
  margin-bottom: 10px;
  transition: background var(--transition);
}

.insights .card:hover .tag {
  background: var(--primary);
  color: #fff;
}

.insights .card a {
  font-weight: 600;
}

/* ===== FAQ ===== */
.faq .grid {
  grid-template-columns: 1fr 1fr;
  gap: 15px;
}

.faq-item {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: all var(--transition);
}

.faq-item:hover {
  box-shadow: var(--shadow-hover);
}

.faq-question {
  width: 100%;
  padding: 18px 25px;
  background: none;
  border: none;
  text-align: left;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: color var(--transition);
}

.faq-question:hover {
  color: var(--primary);
}

.faq-question .arrow {
  transition: transform var(--transition);
  font-size: 1.2rem;
}

.faq-item.active .faq-question .arrow {
  transform: rotate(180deg);
}

.faq-answer {
  padding: 0 25px 18px;
  display: none;
  color: var(--gray);
  line-height: 1.6;
  animation: fadeIn 0.3s ease;
}

.faq-item.active .faq-answer {
  display: block;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ===== HowTo ===== */
.howto .steps {
  display: grid;
  gap: 20px;
  counter-reset: step;
}

.howto .step {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  padding: 25px;
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: all var(--transition);
}

.howto .step:hover {
  transform: translateX(5px);
  box-shadow: var(--shadow-hover);
}

.howto .step .num {
  flex-shrink: 0;
  width: 50px;
  height: 50px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  font-weight: 700;
  transition: transform var(--transition);
}

.howto .step:hover .num {
  transform: scale(1.1);
}

/* ===== Contact ===== */
.contact .grid {
  grid-template-columns: 1fr 1fr;
  gap: 50px;
}

.contact-info .item {
  display: flex;
  gap: 15px;
  margin-bottom: 20px;
  padding: 15px;
  background: var(--card-bg);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow);
  transition: all var(--transition);
}

.contact-info .item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
}

.contact-info .item .icon {
  font-size: 1.5rem;
  color: var(--primary);
}

/* 联系表单 */
.contact form input,
.contact form textarea {
  padding: 12px;
  border: 1px solid #ddd;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  background: var(--card-bg);
  color: var(--text);
  transition: border-color var(--transition), box-shadow var(--transition);
}

.contact form input:focus,
.contact form textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-light);
}

body.dark .contact form input,
body.dark .contact form textarea {
  border-color: #444;
  background: #2a2a2a;
  color: #e0e0e0;
}

/* ===== Footer ===== */
.footer {
  background: var(--dark);
  color: rgba(255, 255, 255, 0.8);
  padding: 60px 0 30px;
}

.footer .grid {
  grid-template-columns: 2fr 1fr 1fr 1fr;
}

.footer h4 {
  color: #fff;
  margin-bottom: 20px;
  font-size: 1.1rem;
  position: relative;
  display: inline-block;
}

.footer h4::after {
  content: '';
  display: block;
  width: 30px;
  height: 2px;
  background: var(--primary);
  margin-top: 5px;
}

.footer ul {
  list-style: none;
}

.footer ul li {
  margin-bottom: 10px;
}

.footer ul li a {
  color: rgba(255, 255, 255, 0.7);
  transition: color var(--transition);
  position: relative;
  padding-left: 0;
}

.footer ul li a::before {
  content: '›';
  position: absolute;
  left: -15px;
  opacity: 0;
  transition: left var(--transition), opacity var(--transition);
}

.footer ul li a:hover {
  color: var(--primary);
  padding-left: 15px;
}

.footer ul li a:hover::before {
  left: 0;
  opacity: 1;
}

.footer .bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  margin-top: 40px;
  padding-top: 30px;
  text-align: center;
  font-size: 0.9rem;
}

.footer .bottom a {
  color: rgba(255, 255, 255, 0.7);
  margin: 0 10px;
  transition: color var(--transition);
}

.footer .bottom a:hover {
  color: var(--primary);
}

/* ===== 返回顶部 ===== */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 50px;
  height: 50px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 50%;
  font-size: 1.5rem;
  cursor: pointer;
  display: none;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 15px rgba(255, 102, 0, 0.3);
  transition: all var(--transition);
  z-index: 999;
  opacity: 0;
  transform: translateY(20px);
}

.back-to-top.show {
  display: flex;
  opacity: 1;
  transform: translateY(0);
}

.back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(255, 102, 0, 0.4);
}

/* ===== 暗色切换 ===== */
.dark-toggle {
  position: fixed;
  bottom: 30px;
  left: 30px;
  width: 50px;
  height: 50px;
  background: var(--card-bg);
  color: var(--text);
  border: 1px solid var(--gray);
  border-radius: 50%;
  font-size: 1.3rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow);
  transition: all var(--transition);
  z-index: 999;
}

.dark-toggle:hover {
  transform: scale(1.1);
  box-shadow: var(--shadow-hover);
}

/* ===== 搜索条 ===== */
.search-bar {
  display: flex;
  max-width: 500px;
  margin: 20px auto;
  background: var(--card-bg);
  border-radius: 50px;
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: box-shadow var(--transition);
}

.search-bar:focus-within {
  box-shadow: 0 0 0 3px var(--primary-light);
}

.search-bar input {
  flex: 1;
  padding: 14px 20px;
  border: none;
  background: transparent;
  font-size: 1rem;
  color: var(--text);
  outline: none;
}

.search-bar input::placeholder {
  color: var(--gray);
}

.search-bar button {
  padding: 14px 25px;
  background: var(--primary);
  color: #fff;
  border: none;
  cursor: pointer;
  font-weight: 600;
  transition: background var(--transition);
}

.search-bar button:hover {
  background: var(--primary-hover);
}

/* ===== 辅助 ===== */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

/* ===== 滚动动画 ===== */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== 毛玻璃效果 ===== */
.glass {
  background: var(--glass-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
}

/* ===== 响应式微调 ===== */
@media (max-width: 480px) {
  .hero h1 {
    font-size: 1.8rem;
  }
  .hero .btn {
    font-size: 0.9rem;
    padding: 12px 25px;
  }
  .company-info {
    grid-template-columns: 1fr;
  }
  .footer .grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
}

/* ===== 暗色模式 @media 查询 ===== */
@media (prefers-color-scheme: dark) {
  body:not(.dark) {
    --bg: #121212;
    --text: #e0e0e0;
    --card-bg: #1e1e1e;
    --light: #2a2a2a;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
    --shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.5);
    --gradient-card: linear-gradient(145deg, #1e1e1e, #252525);
  }
}