:root {
  --primary: #4f6ef7;
  --primary-dark: #3b55d9;
  --primary-light: #eef1ff;
  --ink: #1a2333;
  --ink-soft: #4a5568;
  --ink-mute: #8492a6;
  --bg: #ffffff;
  --bg-alt: #f7f8fc;
  --border: #e6e9f0;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow: 0 10px 30px rgba(26, 35, 51, 0.08);
  --shadow-lg: 0 20px 50px rgba(26, 35, 51, 0.12);
  --max-width: 1080px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

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

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

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

/* ---------- Nav ---------- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s, box-shadow 0.3s;
}

.nav.scrolled {
  border-bottom-color: var(--border);
  box-shadow: 0 2px 12px rgba(26, 35, 51, 0.05);
}

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

.logo {
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.5px;
}

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

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

.nav-links a {
  font-size: 15px;
  color: var(--ink-soft);
  position: relative;
  padding: 4px 0;
  transition: color 0.2s;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 2px;
  background: var(--primary);
  border-radius: 2px;
  transition: width 0.25s;
}

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

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  flex-direction: column;
  gap: 5px;
}

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

.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;
  justify-content: center;
  position: relative;
  overflow: hidden;
  padding: 120px 24px 80px;
  text-align: center;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(600px 400px at 15% 20%, rgba(79, 110, 247, 0.1), transparent 60%),
    radial-gradient(500px 380px at 85% 30%, rgba(79, 110, 247, 0.08), transparent 60%),
    radial-gradient(700px 500px at 60% 90%, rgba(59, 85, 217, 0.06), transparent 60%);
}

.hero-content {
  max-width: 720px;
  animation: fadeUp 0.9s ease both;
}

.avatar-wrap {
  margin-bottom: 24px;
}

.avatar {
  width: 104px;
  height: 104px;
  margin: 0 auto;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  font-size: 36px;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  letter-spacing: -1px;
  box-shadow: 0 12px 32px rgba(79, 110, 247, 0.35);
  position: relative;
}

.avatar::after {
  content: "";
  position: absolute;
  inset: -6px;
  border-radius: 50%;
  border: 2px dashed rgba(79, 110, 247, 0.35);
  animation: spin 18s linear infinite;
}

.hero-name {
  font-size: clamp(30px, 5vw, 46px);
  font-weight: 800;
  letter-spacing: -1px;
  margin-bottom: 12px;
}

.hero-role {
  font-size: clamp(17px, 2.5vw, 21px);
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 16px;
}

.hero-desc {
  font-size: 16px;
  color: var(--ink-soft);
  max-width: 520px;
  margin: 0 auto 36px;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  border: 2px solid transparent;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s, color 0.2s;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 6px 18px rgba(79, 110, 247, 0.3);
}

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 10px 26px rgba(79, 110, 247, 0.4);
}

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

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

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  margin-top: 56px;
  flex-wrap: wrap;
}

.stat {
  text-align: center;
}

.stat-num {
  display: block;
  font-size: 28px;
  font-weight: 800;
  color: var(--ink);
}

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

.scroll-hint {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  opacity: 0.7;
}

.mouse {
  display: block;
  width: 24px;
  height: 40px;
  border: 2px solid var(--ink-mute);
  border-radius: 14px;
  position: relative;
}

.wheel {
  position: absolute;
  top: 7px;
  left: 50%;
  transform: translateX(-50%);
  width: 4px;
  height: 8px;
  border-radius: 2px;
  background: var(--primary);
  animation: wheel 1.8s ease infinite;
}

/* ---------- Section ---------- */
.section {
  padding: 96px 0;
}

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

.section-title {
  font-size: clamp(26px, 4vw, 34px);
  font-weight: 800;
  letter-spacing: -0.5px;
  text-align: center;
}

.section-sub {
  text-align: center;
  color: var(--ink-mute);
  font-size: 14px;
  letter-spacing: 3px;
  text-transform: uppercase;
  margin: 8px 0 56px;
}

/* ---------- About ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 40px;
  align-items: start;
}

.about-text p {
  color: var(--ink-soft);
  font-size: 16px;
  margin-bottom: 16px;
}

.about-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.tag {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 999px;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 13px;
  font-weight: 600;
}

.tag-small {
  font-size: 12px;
  padding: 4px 10px;
}

.about-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
}

.about-card h3 {
  font-size: 17px;
  margin-bottom: 18px;
}

.info-list li {
  display: flex;
  justify-content: space-between;
  padding: 10px 0;
  border-bottom: 1px dashed var(--border);
  font-size: 14px;
}

.info-list li:last-child {
  border-bottom: none;
}

.info-list li span:first-child {
  color: var(--ink-mute);
}

.info-list li span:last-child {
  font-weight: 600;
}

.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: #16a34a;
}

.status-badge .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #22c55e;
  box-shadow: 0 0 0 3px rgba(34, 197, 94, 0.2);
}

.about-links {
  display: flex;
  gap: 10px;
  margin-top: 20px;
}

.social {
  padding: 8px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: var(--ink-soft);
  transition: all 0.2s;
}

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

/* ---------- Skills ---------- */
.skills-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px 48px;
}

.skill-head {
  display: flex;
  justify-content: space-between;
  margin-bottom: 10px;
  font-size: 15px;
}

.skill-name {
  font-weight: 600;
}

.skill-pct {
  color: var(--primary);
  font-weight: 700;
}

.skill-bar {
  height: 8px;
  background: var(--border);
  border-radius: 999px;
  overflow: hidden;
}

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

/* ---------- Projects ---------- */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

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

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

.project-thumb {
  height: 160px;
  background-size: cover;
  background-position: center;
}

.thumb-1 {
  background: linear-gradient(135deg, #4f6ef7, #8a5cf6);
}

.thumb-2 {
  background: linear-gradient(135deg, #0ea5e9, #6366f1);
}

.thumb-3 {
  background: linear-gradient(135deg, #f59e0b, #ef4444);
}

.project-thumb {
  position: relative;
}

.project-thumb::before {
  content: attr(data-icon);
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 40px;
}

.thumb-1::before {
  content: "🗂️";
}

.thumb-2::before {
  content: "🛠️";
}

.thumb-3::before {
  content: "📊";
}

.project-body {
  padding: 22px;
}

.project-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
}

.year {
  font-size: 13px;
  color: var(--ink-mute);
}

.project-title {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 8px;
}

.project-desc {
  font-size: 14px;
  color: var(--ink-soft);
  margin-bottom: 16px;
}

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

.project-tech span {
  font-size: 12px;
  padding: 3px 10px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--ink-soft);
}

/* ---------- Contact ---------- */
.contact-wrap {
  max-width: 640px;
}

.contact-desc {
  text-align: center;
  color: var(--ink-soft);
  margin-bottom: 36px;
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

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

.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 14px 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-family: inherit;
  color: var(--ink);
  background: #fff;
  transition: border-color 0.2s, box-shadow 0.2s;
  resize: vertical;
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(79, 110, 247, 0.15);
}

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

.form-tip {
  text-align: center;
  font-size: 14px;
  color: #16a34a;
  min-height: 20px;
  margin-top: 12px;
}

.contact-alt {
  text-align: center;
  margin-top: 32px;
  font-size: 14px;
  color: var(--ink-mute);
}

.contact-alt a {
  color: var(--primary);
  font-weight: 600;
}

/* ---------- Footer ---------- */
.footer {
  background: var(--ink);
  color: rgba(255, 255, 255, 0.6);
  padding: 40px 0;
  font-size: 14px;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- Animations ---------- */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

@keyframes wheel {
  0% {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
  }
  100% {
    opacity: 0;
    transform: translateX(-50%) translateY(12px);
  }
}

.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

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

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .about-grid {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 640px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: rgba(255, 255, 255, 0.98);
    padding: 16px 24px 24px;
    gap: 4px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow);
    transform: translateY(-8px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.25s, transform 0.25s;
  }

  .nav-links.open {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
  }

  .nav-links a {
    display: block;
    padding: 12px 0;
  }

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

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

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

  .hero-stats {
    gap: 32px;
  }

  .section {
    padding: 72px 0;
  }
}