/* === 基础重置 & 变量 === */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary: #4f46e5;
  --primary-dark: #4338ca;
  --primary-light: #e0e7ff;
  --bg: #f8fafc;
  --bg-card: #ffffff;
  --text: #1e293b;
  --text-light: #64748b;
  --border: #e2e8f0;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.08), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
  --radius: 16px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

/* === 导航栏 === */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  transition: var(--transition);
}

.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-logo {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  letter-spacing: -0.5px;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 8px;
}

.nav-menu a {
  text-decoration: none;
  color: var(--text-light);
  padding: 8px 16px;
  border-radius: 8px;
  font-weight: 500;
  font-size: 0.95rem;
  transition: var(--transition);
}

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

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

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 99px;
  transition: var(--transition);
}

/* === Hero === */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 80px;
  padding: 120px 24px 80px;
  max-width: 1100px;
  margin: 0 auto;
}

.hero-content {
  flex: 1;
}

.hero-greeting {
  font-size: 1.2rem;
  color: var(--primary);
  font-weight: 500;
  margin-bottom: 8px;
}

.hero-name {
  font-size: 3.5rem;
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -1px;
  color: var(--text);
  background: linear-gradient(135deg, #4f46e5, #7c3aed);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-title {
  font-size: 1.25rem;
  color: var(--text-light);
  margin-top: 12px;
  font-weight: 500;
}

.hero-desc {
  font-size: 1.05rem;
  color: #94a3b8;
  margin-top: 8px;
  max-width: 420px;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  margin-top: 36px;
}

.btn {
  display: inline-flex;
  align-items: center;
  padding: 12px 28px;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  font-family: inherit;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(79, 70, 229, 0.35);
}

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

.btn-outline:hover {
  background: var(--primary-light);
  transform: translateY(-2px);
}

.hero-visual {
  flex: 1;
  display: flex;
  justify-content: center;
}

.hero-avatar {
  width: 300px;
  height: 300px;
  border-radius: 50%;
  background: linear-gradient(135deg, #4f46e5, #7c3aed, #a78bfa);
  position: relative;
  animation: float 6s ease-in-out infinite;
}

.hero-avatar::after {
  content: '👨‍💻';
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 80px;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-20px); }
}

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

.section-title {
  text-align: center;
  font-size: 2.2rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 56px;
  position: relative;
}

.section-title::after {
  content: '';
  display: block;
  width: 50px;
  height: 4px;
  background: var(--primary);
  border-radius: 99px;
  margin: 14px auto 0;
}

/* === 关于我 === */
.about {
  background: var(--bg-card);
}

.about-content {
  max-width: 720px;
  margin: 0 auto;
}

.about-text p {
  font-size: 1.05rem;
  color: var(--text-light);
  margin-bottom: 20px;
  line-height: 1.9;
}

.about-info {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  margin-top: 32px;
}

.info-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.95rem;
  color: var(--text);
  font-weight: 500;
}

.info-item span {
  font-size: 1.2rem;
}

/* === 技能 === */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.skill-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 24px;
  text-align: center;
  transition: var(--transition);
}

.skill-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}

.skill-icon {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.skill-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--text);
}

.skill-card p {
  font-size: 0.9rem;
  color: var(--text-light);
  line-height: 1.6;
}

/* === 项目 === */
.projects {
  background: var(--bg-card);
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.project-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: var(--transition);
}

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

.project-img {
  height: 180px;
  background: linear-gradient(135deg, #4f46e5, #7c3aed);
}

.project-img-1 {
  background: linear-gradient(135deg, #4f46e5, #6366f1);
}

.project-img-2 {
  background: linear-gradient(135deg, #7c3aed, #a78bfa);
}

.project-img-3 {
  background: linear-gradient(135deg, #2563eb, #60a5fa);
}

.project-info {
  padding: 24px;
}

.project-info h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.project-info p {
  font-size: 0.9rem;
  color: var(--text-light);
  margin-bottom: 16px;
  line-height: 1.6;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.project-tags span {
  background: var(--primary-light);
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 99px;
}

/* === 联系 === */
.contact-subtitle {
  text-align: center;
  color: var(--text-light);
  margin-bottom: 40px;
  margin-top: -36px;
  font-size: 1rem;
}

.contact-form {
  max-width: 600px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.contact-form .form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 14px 18px;
  border: 2px solid var(--border);
  border-radius: 12px;
  font-size: 0.95rem;
  font-family: inherit;
  color: var(--text);
  background: var(--bg-card);
  transition: var(--transition);
  outline: none;
}

.contact-form input:focus,
.contact-form textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(79, 70, 229, 0.1);
}

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

.contact-form .btn {
  align-self: flex-start;
}

.social-links {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-top: 48px;
}

.social-link {
  font-size: 2rem;
  text-decoration: none;
  transition: var(--transition);
}

.social-link:hover {
  transform: translateY(-4px) scale(1.15);
}

/* === Footer === */
.footer {
  text-align: center;
  padding: 32px 24px;
  border-top: 1px solid var(--border);
  color: var(--text-light);
  font-size: 0.9rem;
}

/* === 响应式 === */
@media (max-width: 900px) {
  .hero {
    flex-direction: column-reverse;
    text-align: center;
    gap: 40px;
    padding-top: 100px;
  }

  .hero-desc {
    max-width: 100%;
  }

  .hero-buttons {
    justify-content: center;
  }

  .hero-name {
    font-size: 2.5rem;
  }

  .hero-avatar {
    width: 200px;
    height: 200px;
  }

  .hero-avatar::after {
    font-size: 56px;
  }

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

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

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

@media (max-width: 600px) {
  .nav-menu {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    flex-direction: column;
    padding: 16px 24px;
    gap: 4px;
    border-bottom: 1px solid var(--border);
    transform: translateY(-120%);
    transition: var(--transition);
  }

  .nav-menu.active {
    transform: translateY(0);
  }

  .nav-toggle {
    display: flex;
  }

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

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

  section {
    padding: 64px 0;
  }

  .section-title {
    font-size: 1.8rem;
  }

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