/* ===== 基础重置 & 变量 ===== */
:root {
  --bg: #FFFFFF;
  --bg-alt: #F7F8FA;
  --text-primary: #1A1A2E;
  --text-secondary: #4A4A68;
  --text-muted: #8888A0;
  --accent: #2563EB;
  --accent-light: #EFF6FF;
  --accent-dark: #1D4ED8;
  --border: #E8E8EE;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.04);
  --shadow: 0 4px 16px rgba(0,0,0,0.06);
  --radius: 10px;
  --radius-sm: 6px;
  --max-width: 1100px;
}

* {
  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", "Helvetica Neue", Arial, sans-serif;
  color: var(--text-primary);
  background: var(--bg);
  line-height: 1.7;
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 32px;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: var(--accent-dark);
}

/* ===== 导航栏 ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s, box-shadow 0.3s;
}

.navbar.scrolled {
  border-bottom-color: var(--border);
  box-shadow: var(--shadow-sm);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.nav-logo {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.3px;
}

.nav-logo:hover {
  color: var(--accent);
}

.nav-links {
  display: flex;
  gap: 28px;
}

.nav-links a {
  font-size: 14px;
  color: var(--text-secondary);
  font-weight: 500;
  transition: color 0.2s;
}

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

.btn-download-pdf {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  background: var(--accent);
  color: #fff;
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 600;
  transition: background 0.2s, transform 0.15s;
}

.btn-download-pdf:hover {
  background: var(--accent-dark);
  color: #fff;
  transform: translateY(-1px);
}

/* ===== Hero / 个人简介 ===== */
.hero {
  padding: 140px 0 80px;
  background: linear-gradient(180deg, var(--accent-light) 0%, var(--bg) 100%);
}

.hero-content {
  max-width: 720px;
}

.hero-greeting {
  font-size: 15px;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: 0.5px;
}

.hero-name {
  font-size: 42px;
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1.2;
  margin-bottom: 12px;
  letter-spacing: -0.5px;
}

.hero-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 15px;
  color: var(--text-secondary);
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.meta-dot {
  color: var(--text-muted);
}

.hero-target {
  font-size: 16px;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 20px;
  padding: 8px 16px;
  background: var(--accent-light);
  border-radius: var(--radius-sm);
  display: inline-block;
}

.hero-intro {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.85;
  margin-bottom: 28px;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.hero-tags .tag {
  padding: 6px 16px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all 0.2s;
}

.hero-tags .tag:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-light);
}

/* ===== 通用 Section ===== */
.section {
  padding: 80px 0;
}

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

.section-title {
  font-size: 26px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 40px;
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.section-num {
  font-size: 14px;
  font-weight: 700;
  color: var(--accent);
  background: var(--accent-light);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  letter-spacing: 0.5px;
}

/* ===== 核心能力 ===== */
.abilities-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.ability-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  transition: box-shadow 0.3s, transform 0.2s;
}

.ability-card:hover {
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}

.ability-card h3 {
  font-size: 17px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.ability-card h3::before {
  content: "";
  display: inline-block;
  width: 4px;
  height: 18px;
  background: var(--accent);
  border-radius: 2px;
  flex-shrink: 0;
}

.ability-card p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 12px;
}

.ability-result {
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  padding: 8px 14px;
  background: var(--accent-light);
  border-radius: var(--radius-sm);
  display: inline-block;
}

/* ===== 经历时间线 ===== */
.timeline {
  position: relative;
  padding-left: 32px;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--border);
}

.timeline-item {
  position: relative;
  margin-bottom: 36px;
}

.timeline-item:last-child {
  margin-bottom: 0;
}

.timeline-dot {
  position: absolute;
  left: -32px;
  top: 8px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--bg);
  border: 3px solid var(--accent);
  z-index: 1;
}

.timeline-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 28px;
  transition: box-shadow 0.3s;
}

.timeline-card:hover {
  box-shadow: var(--shadow);
}

.timeline-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 8px;
  flex-wrap: wrap;
}

.timeline-header h3 {
  font-size: 17px;
  font-weight: 700;
  color: var(--text-primary);
}

.timeline-time {
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 500;
  white-space: nowrap;
  flex-shrink: 0;
}

.timeline-role {
  font-size: 14px;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 12px;
}

.timeline-actions {
  list-style: none;
  margin-bottom: 16px;
}

.timeline-actions li {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.8;
  padding-left: 16px;
  position: relative;
  margin-bottom: 4px;
}

.timeline-actions li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  opacity: 0.5;
}

.timeline-result {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.result-item {
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  padding: 5px 14px;
  background: var(--accent-light);
  border-radius: 20px;
}

/* 高亮数字 */
.highlight-num {
  font-weight: 700;
  color: var(--accent);
}

/* ===== 专业技能 ===== */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.skill-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: box-shadow 0.3s;
}

.skill-card:hover {
  box-shadow: var(--shadow);
}

.skill-card h3 {
  font-size: 15px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--accent-light);
}

.skill-card ul {
  list-style: none;
}

.skill-card li {
  font-size: 14px;
  color: var(--text-secondary);
  padding: 3px 0;
  padding-left: 14px;
  position: relative;
}

.skill-card li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
  opacity: 0.4;
}

.skill-note {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px dashed var(--border);
  font-style: italic;
}

/* ===== 持续学习 ===== */
.learning-note {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 24px;
  margin-top: -20px;
}

.learning-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.learning-tag {
  padding: 10px 22px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 24px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all 0.2s;
}

.learning-tag:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-light);
}

/* ===== 教育背景 ===== */
.edu-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
}

.edu-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 20px;
  flex-wrap: wrap;
  gap: 12px;
}

.edu-header h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
}

.edu-time {
  font-size: 14px;
  color: var(--text-muted);
  font-weight: 500;
}

.edu-major {
  font-size: 15px;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 20px;
}

.edu-details {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.edu-detail-group h4 {
  font-size: 13px;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 10px;
}

.edu-detail-group ul {
  list-style: none;
}

.edu-detail-group li {
  font-size: 14px;
  color: var(--text-secondary);
  padding: 3px 0;
  padding-left: 14px;
  position: relative;
}

.edu-detail-group li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
  opacity: 0.4;
}

/* ===== 联系方式 ===== */
.contact-box {
  text-align: center;
  padding: 48px 32px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.contact-label {
  font-size: 13px;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 8px;
}

.contact-email {
  font-size: 22px;
  font-weight: 700;
  color: var(--accent);
  display: inline-block;
  margin-bottom: 16px;
}

.contact-closing {
  font-size: 14px;
  color: var(--text-muted);
}

/* ===== 页脚 ===== */
.footer {
  padding: 32px 0;
  text-align: center;
  border-top: 1px solid var(--border);
}

.footer p {
  font-size: 13px;
  color: var(--text-muted);
}

/* ===== 滚动动画 ===== */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  .container {
    padding: 0 20px;
  }

  .hero {
    padding: 110px 0 60px;
  }

  .hero-name {
    font-size: 32px;
  }

  .section {
    padding: 60px 0;
  }

  .section-title {
    font-size: 22px;
    margin-bottom: 28px;
  }

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

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

  .edu-details {
    grid-template-columns: 1fr;
  }

  .nav-links {
    display: none;
  }

  .btn-download-pdf {
    font-size: 12px;
    padding: 6px 12px;
  }

  .timeline-header {
    flex-direction: column;
    gap: 4px;
  }
}

@media (max-width: 480px) {
  .hero-name {
    font-size: 28px;
  }

  .hero-meta {
    font-size: 13px;
  }

  .hero-target {
    font-size: 14px;
  }

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

  .contact-email {
    font-size: 18px;
  }
}