:root {
  --bg: #0f172a;
  --bg-alt: #1e293b;
  --card: #1e293b;
  --text: #e2e8f0;
  --muted: #94a3b8;
  --primary: #38bdf8;
  --primary-dark: #0ea5e9;
  --radius: 12px;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
}

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- 导航栏 ---------- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  z-index: 100;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text);
  text-decoration: none;
  letter-spacing: 0.5px;
}

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

.nav-links {
  display: flex;
  list-style: none;
  gap: 32px;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.95rem;
  transition: color 0.25s;
}

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

.menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text);
  font-size: 1.5rem;
  cursor: pointer;
}

/* ---------- Hero ---------- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: radial-gradient(ellipse at 20% 20%, #1e3a5f 0%, transparent 50%),
    radial-gradient(ellipse at 80% 80%, #164e63 0%, transparent 50%);
  padding-top: 64px;
}

.hero-content {
  max-width: 640px;
}

.hero-greet {
  color: var(--primary);
  font-size: 1.1rem;
  margin-bottom: 8px;
  letter-spacing: 2px;
}

.hero-name {
  font-size: clamp(2.8rem, 7vw, 4.2rem);
  font-weight: 900;
  line-height: 1.15;
  background: linear-gradient(135deg, #e2e8f0, #38bdf8);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 16px;
}

.hero-title {
  font-size: 1.35rem;
  color: var(--primary-dark);
  font-weight: 600;
  margin-bottom: 20px;
}

.hero-desc {
  color: var(--muted);
  font-size: 1.05rem;
  margin-bottom: 32px;
}

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

/* ---------- 按钮 ---------- */
.btn {
  display: inline-block;
  padding: 12px 28px;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  transition: all 0.25s;
  border: 1px solid transparent;
  cursor: pointer;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #0b1220;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(56, 189, 248, 0.35);
}

.btn-outline {
  border-color: rgba(148, 163, 184, 0.4);
  color: var(--text);
}

.btn-outline:hover {
  border-color: var(--primary);
  color: var(--primary);
}

/* ---------- 通用 Section ---------- */
.section {
  padding: 100px 0;
}

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

.section-title {
  font-size: 2rem;
  font-weight: 800;
  text-align: center;
  margin-bottom: 56px;
  position: relative;
}

.section-title::after {
  content: "";
  display: block;
  width: 56px;
  height: 4px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--primary), transparent);
  margin: 16px auto 0;
}

/* ---------- 关于我 ---------- */
.about-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.about-card {
  background: var(--card);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: transform 0.3s, box-shadow 0.3s;
}

.about-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow);
}

.about-icon {
  font-size: 2rem;
  margin-bottom: 16px;
}

.about-card h3 {
  margin-bottom: 12px;
  font-size: 1.15rem;
}

.about-card p {
  color: var(--muted);
  font-size: 0.95rem;
}

/* ---------- 技能 ---------- */
.skills-grid {
  max-width: 720px;
  margin: 0 auto 48px;
  display: grid;
  gap: 24px;
}

.skill-item {
  background: var(--card);
  border-radius: var(--radius);
  padding: 20px 24px;
  border: 1px solid rgba(255, 255, 255, 0.06);
}

.skill-info {
  display: flex;
  justify-content: space-between;
  margin-bottom: 10px;
  font-size: 0.95rem;
}

.skill-info span:last-child {
  color: var(--primary);
  font-weight: 600;
}

.skill-bar {
  height: 8px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.08);
  overflow: hidden;
}

.skill-fill {
  height: 100%;
  border-radius: 4px;
  background: linear-gradient(90deg, var(--primary-dark), var(--primary));
  width: 0;
  transition: width 1s ease;
}

.tech-tags {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  max-width: 720px;
  margin: 0 auto;
}

.tag {
  padding: 8px 18px;
  border-radius: 999px;
  background: rgba(56, 189, 248, 0.1);
  border: 1px solid rgba(56, 189, 248, 0.25);
  color: var(--primary);
  font-size: 0.9rem;
  font-weight: 500;
}

/* ---------- 项目 ---------- */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 28px;
}

.project-card {
  background: var(--card);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.3s, box-shadow 0.3s;
}

.project-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow);
}

.project-thumb {
  height: 160px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3.5rem;
}

.project-thumb-1 {
  background: linear-gradient(135deg, #164e63, #0f766e);
}

.project-thumb-2 {
  background: linear-gradient(135deg, #312e81, #4338ca);
}

.project-thumb-3 {
  background: linear-gradient(135deg, #7c2d12, #b45309);
}

.project-card h3 {
  padding: 20px 24px 0;
  font-size: 1.15rem;
}

.project-card p {
  padding: 10px 24px 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.project-meta {
  padding: 16px 24px 20px;
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.project-meta span {
  font-size: 0.78rem;
  padding: 4px 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.07);
  color: var(--muted);
}

/* ---------- 联系 ---------- */
.contact-intro {
  text-align: center;
  color: var(--muted);
  margin-bottom: 32px;
}

.contact-actions {
  text-align: center;
  margin-bottom: 40px;
}

.social-links {
  display: flex;
  justify-content: center;
  gap: 16px;
}

.social-link {
  padding: 10px 24px;
  border-radius: 999px;
  border: 1px solid rgba(148, 163, 184, 0.35);
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
  transition: all 0.25s;
}

.social-link:hover {
  color: var(--primary);
  border-color: var(--primary);
}

/* ---------- 页脚 ---------- */
.footer {
  padding: 32px 0;
  text-align: center;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  color: var(--muted);
  font-size: 0.9rem;
}

/* ---------- 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);
}

/* ---------- 响应式 ---------- */
@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--bg-alt);
    flex-direction: column;
    padding: 24px;
    gap: 20px;
    transform: translateY(-100%);
    transition: transform 0.3s ease;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  }

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

  .menu-toggle {
    display: block;
  }

  .section {
    padding: 72px 0;
  }
}