/* 全局样式重置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
}

/* 颜色变量定义 */
:root {
  --black-primary: #121212;    /* 神秘黑 */
  --black-secondary: #1E1E1E;  /* 深灰黑 */
  --yellow-primary: #FFC107;   /* 工程黄 */
  --yellow-light: #FFD54F;     /* 浅黄 */
  --white-primary: #FFFFFF;    /* 纯白 */
  --gray-primary: #757575;     /* 浅灰 */
}

/* 通用样式 */
body {
  background-color: var(--black-primary);
  color: var(--white-primary);
  line-height: 1.6;
}

.container {
  width: 90%;
  max-width: 1200px;
  margin: 0 auto;
}

a {
  text-decoration: none;
  color: var(--yellow-primary);
  transition: color 0.3s ease;
}

a:hover {
  color: var(--yellow-light);
}

/* 头部样式 */
header {
  background-color: var(--black-secondary);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 10px rgba(0,0,0,0.5);
}

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

.logo {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--yellow-primary);
}

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-links a {
  font-size: 1.1rem;
  font-weight: 500;
}

/* 英雄区样式 */
.hero {
  padding: 5rem 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 3rem;
}

.hero-content {
  flex: 1;
}

.hero-title {
  font-size: 3rem;
  margin-bottom: 1.5rem;
  line-height: 1.2;
}

.hero-title span {
  color: var(--yellow-primary);
}

.hero-desc {
  font-size: 1.2rem;
  color: var(--gray-primary);
  margin-bottom: 2rem;
  max-width: 600px;
}

.cta-btn {
  display: inline-block;
  padding: 1rem 2rem;
  background-color: var(--yellow-primary);
  color: var(--black-primary);
  font-size: 1.1rem;
  font-weight: 600;
  border-radius: 8px;
  transition: background-color 0.3s ease;
}

.cta-btn:hover {
  background-color: var(--yellow-light);
  color: var(--black-primary);
}

/* 浮动产品图片样式 */
.hero-image {
  flex: 1;
  position: relative;
}

.floating-img {
  width: 100%;
  max-width: 500px;
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(255, 193, 7, 0.2);
  /* 浮动动画 */
  animation: float 3s ease-in-out infinite;
}

@keyframes float {
  0% { transform: translateY(0px); }
  50% { transform: translateY(-15px); }
  100% { transform: translateY(0px); }
}

/* 产品介绍样式 */
.product-intro {
  padding: 4rem 0;
  background-color: var(--black-secondary);
  margin: 3rem 0;
  border-radius: 12px;
}

.intro-title {
  font-size: 2.2rem;
  text-align: center;
  margin-bottom: 2rem;
  color: var(--yellow-primary);
}

.intro-desc {
  font-size: 1.1rem;
  color: var(--gray-primary);
  text-align: center;
  max-width: 800px;
  margin: 0 auto 3rem;
}

/* 文章列表样式 */
.articles {
  padding: 2rem 0 5rem;
}

.articles-title {
  font-size: 2rem;
  margin-bottom: 2.5rem;
  color: var(--yellow-primary);
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: 2rem;
}

.article-card {
  background-color: var(--black-secondary);
  padding: 1.5rem;
  border-radius: 8px;
  transition: transform 0.3s ease;
}

.article-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 20px rgba(255, 193, 7, 0.1);
}

.article-title {
  font-size: 1.3rem;
  margin-bottom: 1rem;
  color: var(--yellow-primary);
}

.article-desc {
  color: var(--gray-primary);
  font-size: 1rem;
}

/* 下载页样式 */
.download-page {
  padding: 4rem 0;
}

.download-card {
  background-color: var(--black-secondary);
  padding: 2rem;
  border-radius: 12px;
  margin-bottom: 3rem;
  display: flex;
  align-items: center;
  gap: 2rem;
}

.download-icon {
  font-size: 3rem;
  color: var(--yellow-primary);
}

.download-info h3 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.download-info p {
  color: var(--gray-primary);
  margin-bottom: 1rem;
}

.download-btn {
  padding: 0.8rem 1.5rem;
  background-color: var(--yellow-primary);
  color: var(--black-primary);
  border-radius: 6px;
  font-weight: 600;
  display: inline-block;
}

/* 404页面样式 */
.error-page {
  height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
}

.error-code {
  font-size: 8rem;
  color: var(--yellow-primary);
  margin-bottom: 1rem;
}

.error-message {
  font-size: 2rem;
  margin-bottom: 2rem;
}

.error-desc {
  font-size: 1.2rem;
  color: var(--gray-primary);
  margin-bottom: 3rem;
  max-width: 600px;
}

.back-home {
  padding: 1rem 2rem;
  background-color: var(--yellow-primary);
  color: var(--black-primary);
  border-radius: 8px;
  font-weight: 600;
}

/* 页脚样式 */
footer {
  background-color: var(--black-secondary);
  padding: 2rem 0;
  text-align: center;
  margin-top: 3rem;
}

.footer-text {
  color: var(--gray-primary);
}