:root {
  --deep-space-blue: #0B1D3A;
  --deep-space-blue-light: #1A3A6B;
  --gold-start: #F5D061;
  --gold-end: #E8A33D;
  --neon-purple: #9B3CFF;
  --china-red: #E63B3B;
  --text-primary: #FFFFFF;
  --text-secondary: #C0D4F0;
  --text-muted: #8FA3C2;
  --bg-panel: #13294B;
  --border-line: rgba(255, 255, 255, 0.12);
  --font-head: "Arial Black", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  --font-mono: "Roboto Mono", "Source Code Pro", Consolas, monospace;
  --navy-deep: #081226;
  --content-max: 1440px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.7;
  background-color: var(--deep-space-blue);
  color: var(--text-primary);
  min-height: 100vh;
}

ul,
ol {
  list-style: none;
}

a {
  color: inherit;
}

img {
  display: block;
  max-width: 100%;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: none;
  cursor: pointer;
}

:focus-visible {
  outline: 3px solid var(--neon-purple);
  outline-offset: 3px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.container {
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
}

.section {
  padding: 64px 0;
  position: relative;
}

.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 32px;
  flex-wrap: wrap;
}

.section-title-group {
  max-width: 720px;
}

.section-index {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  letter-spacing: 0.1em;
  color: var(--neon-purple);
  margin-bottom: 6px;
}

.section-title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  letter-spacing: 0.02em;
  color: var(--text-primary);
}

.section-desc {
  color: var(--text-secondary);
  margin-top: 8px;
  max-width: 640px;
}

.grid {
  display: grid;
  gap: 24px;
}

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

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

.panel {
  background:
    linear-gradient(135deg, rgba(245, 208, 97, 0.04), rgba(155, 60, 255, 0.03)),
    var(--bg-panel);
  border: 1px solid var(--border-line);
  border-radius: 20px;
  padding: 32px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.35);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.panel:hover {
  transform: translateY(-4px);
  box-shadow: 0 24px 56px rgba(155, 60, 255, 0.18);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 24px;
  border-radius: 999px;
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
  border: 1px solid transparent;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
  cursor: pointer;
}

.btn-primary {
  background: linear-gradient(135deg, var(--gold-start), var(--gold-end));
  color: var(--deep-space-blue);
  box-shadow: 0 8px 24px rgba(232, 163, 61, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(155, 60, 255, 0.4);
}

.btn-outline {
  border-color: rgba(255, 255, 255, 0.25);
  color: var(--text-primary);
  background: transparent;
}

.btn-outline:hover {
  border-color: var(--neon-purple);
  background: rgba(155, 60, 255, 0.1);
  transform: translateY(-2px);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.breadcrumb a {
  color: var(--text-secondary);
  text-decoration: none;
}

.breadcrumb a:hover {
  color: var(--gold-start);
}

.breadcrumb .current {
  color: var(--gold-start);
}

.index-list {
  display: grid;
  gap: 12px;
}

.index-item {
  background: rgba(255, 255, 255, 0.03);
  border-left: 2px solid var(--neon-purple);
  border-radius: 0 12px 12px 0;
  padding: 16px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  transition: background 0.25s ease;
}

.index-item:hover {
  background: rgba(155, 60, 255, 0.08);
}

.index-item a {
  color: var(--text-primary);
  text-decoration: none;
  font-weight: 600;
}

.index-item .meta {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  white-space: nowrap;
}

.mono-label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  letter-spacing: 0.06em;
}

.data-list {
  display: grid;
  gap: 0;
}

.data-list li {
  padding: 16px 0;
  border-bottom: 1px solid var(--border-line);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
}

.data-list li:last-child {
  border-bottom: 0;
}

.data-num {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 2rem;
  background: linear-gradient(135deg, var(--gold-start), var(--gold-end));
  -webkit-background-clip: text;
  background-clip: text;
  color: var(--gold-start);
}

.skill-tree {
  display: flex;
  flex-direction: column;
}

.skill-step {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  position: relative;
  padding-bottom: 24px;
}

.skill-node {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--neon-purple), var(--deep-space-blue-light));
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-primary);
  box-shadow: 0 0 0 4px rgba(155, 60, 255, 0.15);
  z-index: 1;
}

.skill-line {
  border-left: 1px dashed var(--border-line);
  height: 24px;
  margin-left: 15px;
}

.image-frame {
  position: relative;
  overflow: hidden;
  border-radius: 16px;
  background: linear-gradient(135deg, var(--deep-space-blue-light), var(--bg-panel));
  border: 1px solid var(--border-line);
  min-height: 200px;
}

.image-frame img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.image-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 50%, rgba(11, 29, 58, 0.4));
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(11, 29, 58, 0.85);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-line);
}

.site-header::before {
  content: "";
  display: block;
  height: 3px;
  background: linear-gradient(90deg, var(--gold-start), var(--gold-end), var(--neon-purple));
}

.header-inner {
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 12px 24px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  position: relative;
}

.site-header .header-brand {
  display: flex;
  align-items: center;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 16px;
  text-decoration: none;
  color: var(--text-primary);
}

.brand-logo {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 2.4rem;
  line-height: 1;
  background: linear-gradient(135deg, var(--gold-start), var(--gold-end));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: var(--gold-start);
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.3;
}

.brand-name {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1.4rem;
  letter-spacing: 0.04em;
  color: var(--text-primary);
}

.brand-tagline {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  color: var(--text-muted);
}

.site-nav {
  flex-basis: 100%;
  width: 100%;
  display: flex;
  justify-content: center;
  margin-top: 8px;
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 4px;
}

.nav-list a {
  display: block;
  padding: 8px 16px;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.25s ease, background 0.25s ease;
}

.nav-list a:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.08);
}

.nav-list a[aria-current="page"] {
  color: var(--gold-start);
  background: rgba(245, 208, 97, 0.08);
  box-shadow: inset 0 0 0 1px rgba(245, 208, 97, 0.3);
}

.nav-toggle {
  display: none;
  position: absolute;
  right: 16px;
  top: 16px;
  z-index: 10;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border-line);
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}

.nav-toggle-line {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.progress-read {
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 3px;
  pointer-events: none;
  overflow: hidden;
}

.progress-read span {
  display: block;
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--gold-start), var(--gold-end), var(--neon-purple));
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 3px;
  background: linear-gradient(135deg, var(--neon-purple), var(--deep-space-blue-light));
  color: var(--text-primary);
  padding: 8px 16px;
  border-radius: 0 0 10px 0;
  text-decoration: none;
  z-index: 1000;
}

.skip-link:focus {
  left: 0;
}

.site-footer {
  background: var(--navy-deep);
  border-top: 1px solid var(--border-line);
  padding: 48px 24px 24px;
}

.footer-main {
  max-width: var(--content-max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 48px;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 12px;
}

.footer-logo {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 2.4rem;
  line-height: 1;
  background: linear-gradient(135deg, var(--gold-start), var(--gold-end));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: var(--gold-start);
}

.footer-name {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1.4rem;
  color: var(--text-primary);
}

.footer-trust {
  color: var(--text-muted);
  font-size: 0.9rem;
  max-width: 420px;
}

.footer-heading {
  font-family: var(--font-head);
  font-size: 1rem;
  font-weight: 900;
  color: var(--text-primary);
  margin-bottom: 16px;
  letter-spacing: 0.04em;
}

.footer-list {
  display: grid;
  gap: 10px;
}

.footer-list a {
  display: inline-flex;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.95rem;
  transition: color 0.2s ease;
}

.footer-list a:hover {
  color: var(--gold-start);
}

.footer-contact {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-contact-line {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.footer-bottom {
  max-width: var(--content-max);
  margin: 48px auto 0;
  padding-top: 24px;
  border-top: 1px solid var(--border-line);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-muted);
}

@media (max-width: 768px) {
  .section {
    padding: 48px 0;
  }

  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }

  .header-inner {
    justify-content: space-between;
    align-items: center;
    padding-top: 12px;
    padding-bottom: 12px;
  }

  .header-inner .header-brand {
    order: 1;
  }

  .nav-toggle {
    order: 2;
    display: flex;
  }

  .site-nav {
    order: 3;
    display: none;
    margin-top: 12px;
  }

  .site-nav[data-open] {
    display: block;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
  }

  .nav-list a {
    border-radius: 12px;
    text-align: center;
  }

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

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }

  .brand-logo {
    font-size: 2rem;
  }

  .brand-name {
    font-size: 1.2rem;
  }

  .container {
    padding-left: 20px;
    padding-right: 20px;
  }

  .section-header {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 480px) {
  .brand-tagline {
    max-width: 140px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .progress-read span {
    transition: none;
  }
}