/* ================= 全局设计系统 ================= */
:root {
  --bg-color: #f7f7f9;
  --surface-color: #ffffff;
  --text-main: #1d1d1f;
  --text-secondary: #86868b;
  --accent-color: #0066cc;
  --accent-hover: #004c99;
  --border-color: #eaeaea;
  --shadow-subtle: 0 4px 20px rgba(0, 0, 0, 0.03);
  --shadow-hover: 0 12px 30px rgba(0, 0, 0, 0.08);
  --border-radius: 12px;
  --spacing-base: 24px;
}

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

body {
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue",
    Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  text-decoration: none;
  color: inherit;
}
img,
video {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ================= 导航栏 ================= */
nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 5%;
  background-color: var(--surface-color);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-logo {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.5px;
}

.nav-links {
  display: flex;
  gap: 24px;
  align-items: center;
}
.nav-link {
  font-size: 0.95rem;
  color: var(--text-secondary);
  transition: color 0.2s;
}
.nav-link:hover {
  color: var(--text-main);
}

.btn-primary {
  background-color: var(--accent-color);
  color: #fff;
  padding: 8px 20px;
  border-radius: 6px;
  font-size: 0.95rem;
  font-weight: 500;
  transition: background-color 0.2s ease;
}
.btn-primary:hover {
  background-color: var(--accent-hover);
}

/* ================= 通用容器 ================= */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 60px 5%;
}

/* ================= 首页英雄区 ================= */
.hero {
  padding: 40px 0 20px;
  text-align: center;
}
.hero h1 {
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: -1px;
}
.hero p {
  font-size: 1.2rem;
  color: var(--text-secondary);
  max-width: 700px;
  margin: 0 auto;
}

/* ================= 主页新增：关于我与技能区 ================= */
.about-section {
  padding: 60px 5%;
  background-color: var(--surface-color);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}
.about-grid {
  max-width: 1100px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 80px;
}
.about-text h2,
.about-details h3 {
  font-size: 1.8rem;
  margin-bottom: 24px;
  font-weight: 700;
  letter-spacing: -0.5px;
}
.about-details h3 {
  font-size: 1.3rem;
  margin-bottom: 16px;
}
.about-text p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 16px;
  line-height: 1.8;
}
.skills-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.skill-tag {
  background: var(--bg-color);
  border: 1px solid var(--border-color);
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 0.9rem;
  color: var(--accent-color);
  font-weight: 600;
}
.honor-list {
  list-style: none;
  color: var(--text-secondary);
}
.honor-list li {
  margin-bottom: 12px;
  padding-left: 24px;
  position: relative;
  font-size: 0.95rem;
}
.honor-list li::before {
  content: "🏆";
  position: absolute;
  left: 0;
  top: 1px;
  font-size: 1rem;
}

/* ================= 项目列表 ================= */
.project-list {
  display: flex;
  flex-direction: column;
  gap: 40px;
}

.project-card {
  display: flex;
  background-color: var(--surface-color);
  border-radius: var(--border-radius);
  overflow: hidden;
  box-shadow: var(--shadow-subtle);
  transition:
    transform 0.3s ease,
    box-shadow 0.3s ease;
  border: 1px solid var(--border-color);
}
.project-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.project-card-img {
  flex: 1.2;
  position: relative;
  background: #efefef;
  overflow: hidden;
}
.project-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  position: absolute;
}

.project-card-content {
  flex: 1;
  padding: 40px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.project-tag {
  font-size: 0.85rem;
  color: var(--accent-color);
  font-weight: 600;
  margin-bottom: 12px;
}
.project-title {
  font-size: 1.7rem;
  margin-bottom: 16px;
  font-weight: 700;
  line-height: 1.3;
}
.project-desc {
  color: var(--text-secondary);
  margin-bottom: 24px;
  font-size: 1.05rem;
}
.project-link {
  color: var(--accent-color);
  font-weight: 600;
  font-size: 0.95rem;
}
.project-link::after {
  content: "→";
  margin-left: 6px;
  transition: transform 0.2s;
  display: inline-block;
}
.project-card:hover .project-link::after {
  transform: translateX(4px);
}

/* ================= 详情页通用样式 ================= */
.project-header {
  text-align: center;
  padding: 40px 0;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 40px;
}
.project-header h1 {
  font-size: 2.5rem;
  margin: 16px 0;
  line-height: 1.2;
}
.project-meta {
  display: flex;
  justify-content: center;
  gap: 40px;
  color: var(--text-secondary);
}
.meta-item strong {
  color: var(--text-main);
  display: block;
  margin-bottom: 4px;
}

.project-body {
  font-size: 1.1rem;
  color: var(--text-main);
  line-height: 1.8;
}
.project-body h2 {
  font-size: 1.5rem;
  margin: 40px 0 20px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-color);
}
.project-body p {
  margin-bottom: 20px;
}

.media-container {
  margin: 30px 0;
  border-radius: var(--border-radius);
  overflow: hidden;
  border: 1px solid var(--border-color);
  background-color: #000;
  box-shadow: var(--shadow-subtle);
}
.media-container video,
.media-container img {
  width: 100%;
  display: block;
}
.media-caption {
  text-align: center;
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-top: 10px;
}

.file-download-list {
  list-style: none;
  margin-top: 20px;
}
.file-download-list li {
  background-color: var(--surface-color);
  border: 1px solid var(--border-color);
  padding: 16px 20px;
  border-radius: 8px;
  margin-bottom: 12px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: border-color 0.2s;
}
.file-download-list li:hover {
  border-color: var(--accent-color);
}
.file-name::before {
  content: "📁";
  margin-right: 12px;
}
.btn-download {
  color: var(--accent-color);
  font-size: 0.95rem;
  font-weight: 600;
}
.btn-download:hover {
  text-decoration: underline;
}

/* 底部声明 */
footer {
  text-align: center;
  padding: 40px 5%;
  color: var(--text-secondary);
  font-size: 0.9rem;
  border-top: 1px solid var(--border-color);
}

/* ================= 响应式设计 ================= */
@media (max-width: 992px) {
  .project-card {
    flex-direction: column;
  }
  .project-card-img {
    min-height: 300px;
    position: relative;
  }
  .project-card-img img {
    position: static;
  }
  .about-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 40px 5%;
  }
  .hero {
    padding: 20px 0;
  }
  .hero h1 {
    font-size: 2.2rem;
  }
  .hero p {
    font-size: 1.05rem;
  }

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

  .project-card-img {
    min-height: 220px;
  }
  .project-card-content {
    padding: 24px;
  }
  .project-title {
    font-size: 1.4rem;
  }

  .project-header h1 {
    font-size: 2rem;
  }
  .project-meta {
    flex-direction: column;
    gap: 16px;
    align-items: center;
  }

  .file-download-list li {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
  .btn-download {
    align-self: flex-end;
  }
}