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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: "Helvetica Neue", "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-weight: 300;
  font-size: 16px;
  line-height: 1.75;
  color: #0B1B3F;
  background: #F4F7FF;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4,
h5,
h6,
p,
ul,
ol,
figure,
blockquote,
dl,
dd,
pre {
  margin: 0;
}

ul,
ol {
  padding: 0;
  list-style: none;
}

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

input,
button,
textarea,
select {
  font: inherit;
}

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

button {
  background: none;
  border: 0;
  cursor: pointer;
}

:root {
  --c-primary: #0B1B3F;
  --c-primary-2: #0E2050;
  --c-accent: #39FF14;
  --c-highlight: #FF6A00;
  --c-card: #E0E8FF;
  --c-dark: #1A1A2E;
  --c-page: #F4F7FF;
  --c-muted: #8A94A6;
  --c-purple: #9B59B6;
  --c-white: #FFFFFF;
  --font-head: "Arial Black", "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Helvetica Neue", "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --container-w: 1240px;
  --header-h: 76px;
  --radius-lg: 28px;
  --radius-md: 16px;
  --radius-sm: 10px;
  --radius-pill: 100px;
  --shadow-sm: 0 4px 16px rgba(11, 27, 63, 0.08);
  --shadow-md: 0 12px 40px rgba(11, 27, 63, 0.16);
  --transition: 0.3s ease;
  --fs-h1: clamp(32px, 4.5vw, 48px);
  --fs-h2: clamp(24px, 3vw, 32px);
  --fs-h3: clamp(18px, 2vw, 24px);
}

:focus-visible {
  outline: 3px solid var(--c-highlight);
  outline-offset: 2px;
}

.container {
  width: min(100% - 48px, var(--container-w));
  margin-inline: auto;
}

.section {
  padding: clamp(56px, 7vw, 96px) 0;
}

.section--tight {
  padding: clamp(32px, 4vw, 48px) 0;
}

.section--dark {
  background: var(--c-primary);
  color: var(--c-white);
}

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 12px 24px;
  margin-bottom: 32px;
}

.section-head__sub {
  font-size: 15px;
  color: var(--c-muted);
  max-width: 40em;
}

.section-title {
  font-family: var(--font-head);
  font-size: var(--fs-h2);
  font-weight: 900;
  line-height: 1.2;
  color: var(--c-primary);
}

.section-title--light {
  color: var(--c-white);
}

.section-label {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-head);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--c-highlight);
  margin-bottom: 12px;
}

.section-label::before {
  content: "";
  display: block;
  width: 24px;
  height: 8px;
  background: var(--c-highlight);
  border-radius: 8px;
  transform: skewX(-20deg);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius-pill);
  font-weight: 700;
  font-size: 15px;
  line-height: 1.4;
  white-space: nowrap;
  transition: transform var(--transition), box-shadow var(--transition), background-color var(--transition), color var(--transition), border-color var(--transition);
}

.btn--primary {
  background: var(--c-accent);
  color: var(--c-primary);
}

.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(57, 255, 20, 0.35);
}

.btn--orange {
  background: var(--c-highlight);
  color: var(--c-white);
}

.btn--orange:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(255, 106, 0, 0.35);
}

.btn--outline {
  border: 2px solid rgba(255, 255, 255, 0.4);
  color: var(--c-white);
}

.btn--outline:hover {
  border-color: var(--c-accent);
  color: var(--c-accent);
}

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

.btn--outline-dark:hover {
  border-color: var(--c-highlight);
  color: var(--c-highlight);
}

.tag {
  display: inline-block;
  padding: 4px 14px;
  border-radius: var(--radius-pill);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
  line-height: 1.6;
}

.tag--green {
  background: rgba(57, 255, 20, 0.14);
  color: var(--c-accent);
  border: 1px solid rgba(57, 255, 20, 0.35);
}

.tag--orange {
  background: rgba(255, 106, 0, 0.14);
  color: var(--c-highlight);
  border: 1px solid rgba(255, 106, 0, 0.35);
}

.tag--purple {
  background: rgba(155, 89, 182, 0.14);
  color: var(--c-purple);
  border: 1px solid rgba(155, 89, 182, 0.35);
}

.skip-link {
  position: fixed;
  top: -100px;
  left: 16px;
  z-index: 3000;
  background: var(--c-accent);
  color: var(--c-primary);
  font-weight: 700;
  padding: 12px 20px;
  border-radius: var(--radius-pill);
  font-size: 14px;
  transition: top 0.3s ease;
}

.skip-link:focus {
  top: 16px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: linear-gradient(135deg, #0B1B3F 0%, #0F2454 70%, #122A66 100%);
  color: var(--c-white);
  box-shadow: 0 4px 24px rgba(11, 27, 63, 0.25);
  transition: box-shadow var(--transition);
}

.site-header[data-scrolled="true"] {
  box-shadow: 0 8px 32px rgba(11, 27, 63, 0.38);
}

.site-header::before {
  content: "";
  position: absolute;
  top: 10px;
  left: 10px;
  width: 18px;
  height: 18px;
  border-left: 2px solid var(--c-accent);
  border-top: 2px solid var(--c-accent);
  border-top-left-radius: 8px;
  opacity: 0.7;
  pointer-events: none;
}

.site-header::after {
  content: "";
  position: absolute;
  bottom: 10px;
  right: 10px;
  width: 18px;
  height: 18px;
  border-right: 2px solid var(--c-highlight);
  border-bottom: 2px solid var(--c-highlight);
  border-bottom-right-radius: 8px;
  opacity: 0.7;
  pointer-events: none;
}

.site-header__glow {
  position: absolute;
  top: 0;
  right: 12%;
  width: 240px;
  height: 100px;
  background: radial-gradient(ellipse, rgba(57, 255, 20, 0.12), transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.site-header__inner {
  position: relative;
  z-index: 1;
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}

.brand__badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 14px;
  background: linear-gradient(135deg, var(--c-accent), var(--c-purple));
  color: var(--c-primary);
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 20px;
  letter-spacing: -0.02em;
  box-shadow: 0 4px 16px rgba(57, 255, 20, 0.25);
  transition: transform var(--transition);
}

.brand:hover .brand__badge {
  transform: rotate(-8deg) scale(1.05);
}

.brand__copy {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand__name {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 18px;
  letter-spacing: 0.02em;
  color: var(--c-white);
}

.brand__name span {
  margin-left: 4px;
  font-size: 0.72em;
  font-weight: 400;
  color: var(--c-accent);
  letter-spacing: 0.08em;
}

.brand__slogan {
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--c-muted);
  white-space: nowrap;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.08);
  transition: background-color var(--transition);
}

.nav-toggle:hover {
  background: rgba(255, 255, 255, 0.14);
}

.nav-toggle__bar {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--c-white);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

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

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

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

.site-nav__list {
  display: flex;
  align-items: center;
  gap: 4px;
}

.site-nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: 10px 18px;
  font-weight: 500;
  font-size: 14px;
  letter-spacing: 0.02em;
  border-radius: var(--radius-pill);
  color: rgba(255, 255, 255, 0.85);
  transition: color var(--transition), background-color var(--transition);
}

.site-nav__link::after {
  content: "";
  position: absolute;
  bottom: 2px;
  left: 50%;
  transform: translateX(-50%);
  width: 18px;
  height: 3px;
  background: var(--c-accent);
  border-radius: 3px;
  opacity: 0;
  transition: opacity var(--transition), width var(--transition);
}

.site-nav__link:hover {
  color: var(--c-white);
  background: rgba(255, 255, 255, 0.06);
}

.site-nav__link:hover::after,
.site-nav__link[aria-current="page"]::after {
  opacity: 1;
  width: 24px;
}

.site-nav__link[aria-current="page"] {
  color: var(--c-white);
  font-weight: 700;
}

.site-nav__num {
  font-size: 10px;
  font-weight: 700;
  color: var(--c-accent);
  opacity: 0.7;
  margin-right: 4px;
  vertical-align: 2px;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  z-index: 2000;
  background: rgba(255, 255, 255, 0.08);
  pointer-events: none;
}

.scroll-progress__bar {
  display: block;
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--c-accent), var(--c-highlight));
  border-radius: 0 3px 3px 0;
}

@media (max-width: 920px) {
  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    padding: 16px;
    background: linear-gradient(180deg, var(--c-primary) 0%, #0E2050 100%);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    box-shadow: 0 24px 48px rgba(11, 27, 63, 0.4);
  }

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

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
  }

  .site-nav__link {
    display: block;
    padding: 14px 20px;
    border-radius: var(--radius-md);
    font-size: 16px;
  }

  .site-nav__link::after {
    display: none;
  }

  .site-nav__link[aria-current="page"] {
    background: rgba(57, 255, 20, 0.1);
    color: var(--c-accent);
  }

  .site-nav__link:hover {
    background: rgba(255, 255, 255, 0.06);
  }

  .site-header__glow {
    right: 0;
    width: 140px;
  }
}

body.nav-lock {
  overflow: hidden;
}

.site-footer {
  position: relative;
  background: var(--c-primary);
  color: var(--c-white);
  margin-top: 96px;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--c-accent) 0%, var(--c-highlight) 55%, var(--c-purple) 100%);
  z-index: 1;
}

.site-footer::after {
  content: "MB";
  position: absolute;
  right: 0;
  bottom: -20px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 180px;
  line-height: 1;
  color: rgba(255, 255, 255, 0.025);
  pointer-events: none;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.4fr 0.8fr 0.8fr 1.2fr;
  gap: 48px;
  padding: 72px 0 48px;
}

.footer-block__title {
  font-family: var(--font-head);
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 16px;
  padding-bottom: 8px;
  position: relative;
}

.footer-block__title::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 32px;
  height: 3px;
  background: var(--c-highlight);
  border-radius: 3px;
}

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

.footer-block__list a {
  font-size: 14px;
  color: var(--c-muted);
  transition: color var(--transition), padding-left var(--transition);
}

.footer-block__list a:hover {
  color: var(--c-accent);
  padding-left: 4px;
}

.footer-block__list--contact a {
  color: var(--c-card);
}

.footer-block__list--contact a:hover {
  color: var(--c-highlight);
}

.footer-block__note {
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-muted);
  margin: 16px 0;
}

.footer-block__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.brand--footer .brand__name {
  font-size: 20px;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 12px 24px;
  padding: 24px 0 28px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 13px;
  color: var(--c-muted);
}

.footer-bottom__copyright {
  font-weight: 500;
}

.footer-bottom__icp {
  padding: 2px 12px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.06);
  font-size: 12px;
  letter-spacing: 0.04em;
}

.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--c-primary);
  color: var(--c-accent);
  font-size: 20px;
  line-height: 1;
  padding-bottom: 6px;
  box-shadow: 0 8px 24px rgba(11, 27, 63, 0.4);
  border: 2px solid rgba(57, 255, 20, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity var(--transition), transform var(--transition), visibility var(--transition), background-color var(--transition), border-color var(--transition);
  z-index: 900;
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--c-primary-2);
  border-color: var(--c-accent);
  transform: translateY(-3px);
}

@media (max-width: 1024px) {
  .footer-top {
    grid-template-columns: 1fr 1fr;
    gap: 40px;
  }
}

@media (max-width: 640px) {
  .footer-top {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 48px 0 32px;
  }

  .footer-bottom {
    flex-direction: column;
    justify-content: center;
    text-align: center;
    gap: 8px;
  }

  .back-to-top {
    right: 16px;
    bottom: 16px;
    width: 42px;
    height: 42px;
  }
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--c-muted);
  padding: 16px 0;
}

.breadcrumbs a {
  color: var(--c-primary);
  font-weight: 500;
  transition: color var(--transition);
}

.breadcrumbs a:hover {
  color: var(--c-highlight);
}

.breadcrumbs__sep {
  color: var(--c-muted);
  opacity: 0.6;
}

.breadcrumbs [aria-current="page"] {
  color: var(--c-muted);
  font-weight: 400;
}

.page-hero {
  position: relative;
  background: var(--c-primary);
  color: var(--c-white);
  padding: clamp(48px, 8vw, 88px) 0;
  overflow: hidden;
}

.page-hero::before {
  content: "";
  position: absolute;
  top: 0;
  right: -40px;
  width: 50%;
  height: 100%;
  background: linear-gradient(135deg, transparent 25%, rgba(57, 255, 20, 0.08) 25%, rgba(57, 255, 20, 0.08) 38%, transparent 38%, transparent 62%, rgba(255, 106, 0, 0.05) 62%, rgba(255, 106, 0, 0.05) 75%, transparent 75%);
  background-size: 48px 48px;
  transform: skewX(-10deg);
  pointer-events: none;
}

.page-hero::after {
  content: "";
  position: absolute;
  bottom: -60px;
  left: -60px;
  width: 180px;
  height: 180px;
  background: radial-gradient(circle, rgba(155, 89, 182, 0.25), transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.page-hero__inner {
  position: relative;
  z-index: 1;
}

.page-hero__title {
  font-family: var(--font-head);
  font-size: var(--fs-h1);
  font-weight: 900;
  line-height: 1.15;
  max-width: 12em;
}

.page-hero__subtitle {
  font-size: 18px;
  line-height: 1.6;
  color: var(--c-muted);
  max-width: 36em;
  margin-top: 16px;
}

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

.card {
  background: var(--c-card);
  border-radius: var(--radius-lg);
  padding: 28px;
  border: 1px solid transparent;
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: rgba(57, 255, 20, 0.4);
}

.card--dark {
  background: var(--c-dark);
  color: var(--c-white);
}

@media (max-width: 1024px) {
  .card-grid {
    --grid-cols: 2;
  }
}

@media (max-width: 640px) {
  .card-grid {
    --grid-cols: 1;
  }
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.filter-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 500;
  border: 1.5px solid rgba(11, 27, 63, 0.15);
  color: var(--c-primary);
  background: var(--c-white);
  transition: background-color var(--transition), color var(--transition), border-color var(--transition);
}

.filter-btn:hover {
  border-color: var(--c-accent);
}

.filter-btn.is-active {
  background: var(--c-primary);
  border-color: var(--c-primary);
  color: var(--c-accent);
}

[data-filter-item].is-hidden {
  display: none;
}

.skill-tree {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 20px;
  margin: 32px 0;
}

.skill-tree__node {
  position: relative;
  background: var(--c-card);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  border: 2px solid transparent;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}

.skill-tree__node:hover {
  border-color: var(--c-accent);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.skill-tree__index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--c-accent);
  color: var(--c-primary);
  font-weight: 900;
  font-size: 14px;
  margin-bottom: 12px;
  box-shadow: 0 4px 12px rgba(57, 255, 20, 0.3);
}

.skill-tree__title {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: var(--fs-h3);
  margin-bottom: 8px;
  color: var(--c-primary);
}

.skill-tree__desc {
  font-size: 14px;
  line-height: 1.6;
  color: var(--c-muted);
}

html.js-enabled [data-reveal] {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

html.js-enabled [data-reveal][data-revealed="true"] {
  opacity: 1;
  transform: none;
}

@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;
    transition-delay: 0ms !important;
  }

  html.js-enabled [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
}