:root {
  --bg: #0b0d12;
  --bg-alt: #11141c;
  --surface: #161a24;
  --text: #e6e8ef;
  --text-dim: #9aa1b2;
  --accent: #6366f1;
  --accent-2: #8b5cf6;
  --border: rgba(255, 255, 255, 0.08);
  --radius: 16px;
  --max-width: 1080px;
  --font: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== 顶部导航 ===== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(11, 13, 18, 0.7);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s ease;
}

.nav.scrolled {
  border-bottom-color: var(--border);
}

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

.brand {
  font-size: 20px;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.brand-dot {
  color: var(--accent);
}

.nav-links {
  display: flex;
  gap: 32px;
}

.nav-links a {
  color: var(--text-dim);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: color 0.2s ease;
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.nav-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle.open span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ===== Hero ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  padding-top: 64px;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 50% at 50% -10%, rgba(99, 102, 241, 0.18), transparent),
    radial-gradient(ellipse 40% 40% at 85% 60%, rgba(139, 92, 246, 0.12), transparent);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  padding: 80px 24px;
}

.hero-eyebrow {
  font-size: 15px;
  color: var(--text-dim);
  margin-bottom: 16px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.hero-title {
  font-size: clamp(56px, 10vw, 104px);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.05;
  background: linear-gradient(120deg, #ffffff 20%, var(--accent) 70%, var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 20px;
}

.hero-subtitle {
  font-size: clamp(18px, 2.5vw, 24px);
  font-weight: 600;
  color: var(--accent);
  min-height: 34px;
  margin-bottom: 20px;
}

.hero-subtitle::after {
  content: '|';
  animation: blink 1s step-end infinite;
  color: var(--accent);
  margin-left: 2px;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

.hero-desc {
  font-size: 17px;
  color: var(--text-dim);
  max-width: 560px;
  margin-bottom: 40px;
}

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

.btn {
  display: inline-block;
  padding: 13px 30px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn-primary {
  background: linear-gradient(120deg, var(--accent), var(--accent-2));
  color: #fff;
  box-shadow: 0 8px 24px rgba(99, 102, 241, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(99, 102, 241, 0.45);
}

.btn-ghost {
  border: 1px solid var(--border);
  color: var(--text);
  background: transparent;
}

.btn-ghost:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.hero-scroll {
  position: absolute;
  bottom: 36px;
  left: 50%;
  transform: translateX(-50%);
}

.scroll-line {
  display: block;
  width: 2px;
  height: 48px;
  background: linear-gradient(var(--accent), transparent);
  animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
  0% { transform: scaleY(0); transform-origin: top; }
  45% { transform: scaleY(1); transform-origin: top; }
  55% { transform: scaleY(1); transform-origin: bottom; }
  100% { transform: scaleY(0); transform-origin: bottom; }
}

/* ===== 通用区块 ===== */
.section {
  padding: 110px 0;
}

.section-alt {
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.section-tag {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--accent);
  margin-bottom: 12px;
  text-transform: uppercase;
}

.section-title {
  font-size: clamp(32px, 5vw, 44px);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

/* ===== 关于 ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 56px;
  align-items: center;
  margin-top: 40px;
}

.about-text p {
  color: var(--text-dim);
  font-size: 17px;
  margin-bottom: 18px;
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.stat {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 16px;
  text-align: center;
}

.stat-num {
  display: block;
  font-size: 34px;
  font-weight: 800;
  color: var(--accent);
  margin-bottom: 6px;
}

.stat-label {
  font-size: 13px;
  color: var(--text-dim);
}

/* ===== 技能 ===== */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 40px;
}

.skill-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  transition: transform 0.3s ease, border-color 0.3s ease;
}

.skill-card:hover {
  transform: translateY(-4px);
  border-color: rgba(99, 102, 241, 0.4);
}

.skill-card h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 18px;
}

.skill-bar {
  height: 6px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 999px;
  overflow: hidden;
  margin-bottom: 14px;
}

.skill-fill {
  display: block;
  height: 100%;
  width: 0;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  transition: width 1.2s cubic-bezier(0.22, 1, 0.36, 1);
}

.skill-card p {
  font-size: 14px;
  color: var(--text-dim);
}

/* ===== 项目 ===== */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 40px;
}

.project-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.3s ease, border-color 0.3s ease;
}

.project-card:hover {
  transform: translateY(-4px);
  border-color: rgba(99, 102, 241, 0.4);
}

.project-thumb {
  height: 140px;
  background:
    radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.15), transparent 50%),
    linear-gradient(135deg, var(--tint), rgba(0, 0, 0, 0.3));
}

.project-body {
  padding: 24px;
}

.project-body h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 10px;
}

.project-body p {
  font-size: 14px;
  color: var(--text-dim);
  margin-bottom: 16px;
}

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

.project-tags span {
  font-size: 12px;
  color: var(--accent);
  background: rgba(99, 102, 241, 0.12);
  border-radius: 999px;
  padding: 4px 12px;
}

/* ===== 联系方式 ===== */
.contact-desc {
  font-size: 17px;
  color: var(--text-dim);
  max-width: 480px;
  margin-bottom: 36px;
}

.contact-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 48px;
}

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

.contact-links a {
  color: var(--text-dim);
  text-decoration: none;
  font-size: 15px;
  font-weight: 500;
  transition: color 0.2s ease;
}

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

/* ===== 页脚 ===== */
.footer {
  border-top: 1px solid var(--border);
  padding: 28px 0;
  text-align: center;
}

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

/* ===== 滚动显示动画 ===== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== 响应式 ===== */
@media (max-width: 860px) {
  .nav-links {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    transform: translateY(-120%);
    transition: transform 0.3s ease;
  }

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

  .nav-links a {
    padding: 16px 24px;
    border-bottom: 1px solid var(--border);
  }

  .nav-toggle {
    display: flex;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

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

  .section {
    padding: 80px 0;
  }
}