:root {
  --bg-deep: #0A0E17;
  --bg-card: #121826;
  --surface-muted: #1B2333;
  --accent-neon: #2AF598;
  --accent-orange: #FF7A00;
  --text-primary: #F2F4F8;
  --text-secondary: #B8C0CC;
  --border-soft: rgba(42, 245, 152, 0.16);
  --overlay-light: rgba(255, 255, 255, 0.05);
  --gradient-blue: rgba(27, 97, 255, 0.2);
  --font-heading: 'Archivo Black', 'Noto Sans SC Black', 'Source Han Sans CN Heavy', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC Regular', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-mono: 'IBM Plex Mono', 'Noto Sans Mono', monospace;
  --container-max: 1280px;
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
}

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

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

body {
  min-height: 100vh;
  background:
    radial-gradient(900px 400px at 50% -100px, rgba(42, 245, 152, 0.05), transparent 65%),
    var(--bg-deep);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

main {
  display: block;
}

#main-content {
  min-height: 70vh;
  outline: none;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-primary);
}

p {
  margin: 0 0 16px;
}

a {
  color: var(--accent-neon);
  text-underline-offset: 4px;
}

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

ul,
ol {
  margin: 0;
  padding: 0;
}

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

::selection {
  background: rgba(42, 245, 152, 0.25);
  color: var(--text-primary);
}

:focus-visible {
  outline: 2px solid var(--accent-neon);
  outline-offset: 3px;
  border-radius: 2px;
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: clamp(20px, 4vw, 40px);
}

.section {
  padding: 80px 0;
}

.section--tight {
  padding: 48px 0;
}

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 5000;
  padding: 12px 24px;
  background: var(--accent-neon);
  color: var(--bg-deep);
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 700;
  line-height: 1;
  text-decoration: none;
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
  transform: translateY(calc(-100% - 24px));
  transition: transform 0.3s var(--ease-out);
}

.skip-link:focus-visible {
  transform: translateY(0);
  color: var(--bg-deep);
  background: var(--accent-neon);
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-neon), var(--accent-orange));
  transform: scaleX(0);
  transform-origin: 0 50%;
  z-index: 4000;
  pointer-events: none;
}

.site-header {
  position: relative;
  z-index: 1000;
  background:
    radial-gradient(1100px 320px at 75% -60px, var(--gradient-blue), transparent 70%),
    var(--bg-deep);
  border-bottom: 1px solid var(--border-soft);
}

.masthead {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  max-width: var(--container-max);
  margin-inline: auto;
  padding: 26px clamp(20px, 4vw, 48px) 18px;
}

.masthead__side {
  display: flex;
  align-items: center;
  min-width: 0;
  overflow: hidden;
}

.masthead__side--left {
  justify-content: flex-start;
}

.masthead__side--right {
  justify-content: flex-end;
}

.masthead__label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.12em;
  color: var(--text-secondary);
  background: var(--overlay-light);
  border: 1px solid var(--border-soft);
  white-space: nowrap;
  clip-path: polygon(0 0, calc(100% - 8px) 0, 100% 8px, 100% 100%, 0 100%);
}

.masthead__label::before {
  content: '';
  width: 6px;
  height: 6px;
  background: var(--accent-orange);
  transform: rotate(45deg);
  flex: none;
}

.masthead__label--solid {
  color: var(--accent-neon);
  border-color: rgba(42, 245, 152, 0.35);
}

.masthead__brand {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  padding: 4px 20px;
  text-decoration: none;
  color: var(--text-primary);
  transition: transform 0.25s var(--ease-out);
}

.masthead__brand:hover,
.masthead__brand:focus-visible {
  transform: translateY(-2px);
  color: var(--text-primary);
}

.masthead__mark {
  display: inline-flex;
  align-items: baseline;
  gap: 2px;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: clamp(30px, 4vw, 46px);
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--text-primary);
  transform: skewX(-5deg);
  transition: color 0.25s ease;
}

.masthead__mark-app {
  color: var(--accent-neon);
}

.masthead__brand:hover .masthead__mark-app,
.masthead__brand:focus-visible .masthead__mark-app {
  color: var(--accent-orange);
}

.masthead__sub {
  display: block;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 9px;
  font-weight: 500;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  text-align: center;
  color: var(--text-secondary);
  white-space: nowrap;
}

.site-nav {
  border-top: 1px solid var(--border-soft);
}

.site-nav__brand {
  display: none;
}

.site-nav__list {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: clamp(20px, 4vw, 48px);
}

.site-nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: 12px 22px 14px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--text-secondary);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.2s ease;
}

.site-nav__link::after {
  content: '';
  position: absolute;
  left: 22px;
  right: 22px;
  bottom: 5px;
  height: 2px;
  background: var(--accent-neon);
  transform: skewX(-32deg) scaleX(0);
  transform-origin: left bottom;
  transition: transform 0.3s var(--ease-out);
}

.site-nav__link:hover,
.site-nav__link:focus-visible,
.site-nav__link[aria-current='page'] {
  color: var(--text-primary);
}

.site-nav__link:hover::after,
.site-nav__link:focus-visible::after,
.site-nav__link[aria-current='page']::after {
  transform: skewX(-32deg) scaleX(1);
}

.site-header__cutline {
  height: 4px;
  background: linear-gradient(90deg, transparent 4%, var(--accent-neon) 28%, var(--accent-orange) 72%, transparent 96%);
  transform: skewY(-0.8deg);
  transform-origin: left center;
  pointer-events: none;
}

.nav-toggle {
  display: none;
}

body.has-open-nav {
  overflow: hidden;
}

@media (max-width: 991px) {
  .site-header {
    position: sticky;
    top: 0;
  }

  .masthead {
    grid-template-columns: 1fr auto;
    padding: 14px 16px 12px;
  }

  .masthead__side {
    display: none;
  }

  .masthead__mark {
    font-size: 30px;
  }

  .masthead__sub {
    font-size: 8px;
    letter-spacing: 0.18em;
    margin-top: 6px;
  }

  .nav-toggle {
    position: absolute;
    top: 14px;
    right: 16px;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 10px 12px;
    background: var(--surface-muted);
    border: 1px solid var(--border-soft);
    color: var(--text-secondary);
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.1em;
    z-index: 302;
    transition: border-color 0.25s ease, color 0.25s ease;
  }

  .nav-toggle:hover,
  .nav-toggle:focus-visible {
    border-color: var(--accent-neon);
    color: var(--text-primary);
  }

  .nav-toggle__bars {
    display: inline-flex;
    flex-direction: column;
    gap: 5px;
  }

  .nav-toggle__bar {
    display: block;
    width: 20px;
    height: 2px;
    background: var(--accent-neon);
    transition: transform 0.3s var(--ease-out), opacity 0.25s ease;
  }

  .nav-toggle__text {
    font-size: 12px;
  }

  .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 {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    z-index: 300;
    width: min(320px, 86vw);
    padding: 96px 24px 32px;
    background:
      radial-gradient(600px 300px at 100% 0%, var(--gradient-blue), transparent 70%),
      var(--bg-deep);
    border-left: 1px solid var(--border-soft);
    border-top: none;
    transform: translateX(102%);
    transition: transform 0.35s var(--ease-out);
    overflow-y: auto;
  }

  .site-nav[data-open='true'] {
    transform: translateX(0);
  }

  .site-nav__brand {
    display: block;
    margin: 4px 8px 28px;
    font-family: var(--font-heading);
    font-size: 22px;
    font-weight: 700;
    letter-spacing: 0.04em;
    color: var(--text-primary);
    transform: skewX(-4deg);
  }

  .site-nav__list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 0;
    padding: 0;
  }

  .site-nav__link {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 8px;
    font-size: 17px;
    border-bottom: 1px solid var(--border-soft);
  }

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

  .site-nav__link[aria-current='page'] {
    color: var(--accent-neon);
    border-left: 3px solid var(--accent-neon);
    padding-left: 16px;
  }
}

@media (max-width: 991px) {
  body.has-open-nav::after {
    content: '';
    position: fixed;
    inset: 0;
    z-index: 150;
    background: rgba(10, 14, 23, 0.64);
    pointer-events: none;
  }
}

.site-footer {
  position: relative;
  background: var(--bg-deep);
  border-top: 1px solid var(--border-soft);
  overflow: hidden;
}

.site-footer__diagonal {
  height: 3px;
  background: linear-gradient(90deg, transparent 8%, var(--accent-orange) 40%, var(--accent-neon) 72%, transparent 96%);
  transform: skewY(-0.8deg);
  transform-origin: left top;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1.3fr 1fr;
  gap: 48px 40px;
  padding: 64px 0 48px;
}

.footer-brand__logo {
  display: inline-block;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 30px;
  line-height: 1.2;
  color: var(--text-primary);
  text-decoration: none;
  transform: skewX(-4deg);
}

.footer-brand__accent {
  color: var(--accent-neon);
}

.footer-brand__text {
  margin-top: 16px;
  max-width: 34ch;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-secondary);
}

.footer-col {
  min-width: 0;
}

.footer-col__title {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 20px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent-neon);
}

.footer-col__title::before {
  content: '';
  width: 22px;
  height: 2px;
  background: var(--accent-orange);
  transform: skewX(-32deg);
}

.footer-col__list {
  display: grid;
  gap: 12px;
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-col__list a {
  color: var(--text-secondary);
  font-size: 15px;
  text-decoration: none;
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.footer-col__list a:hover,
.footer-col__list a:focus-visible {
  color: var(--accent-neon);
  padding-left: 4px;
}

.footer-col__list--contact li {
  display: grid;
  gap: 2px;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.6;
  overflow-wrap: anywhere;
}

.footer-col__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-primary);
}

.footer-bottom {
  border-top: 1px solid var(--border-soft);
  padding: 18px 0 22px;
}

.footer-bottom__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--text-secondary);
}

@media (max-width: 991px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 40px 32px;
    padding: 48px 0 40px;
  }
}

@media (max-width: 599px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 40px 0 32px;
  }

  .footer-bottom__inner {
    flex-direction: column;
    align-items: flex-start;
    font-size: 11px;
  }
}

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

.grid--2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid--3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid--4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

@media (max-width: 991px) {
  .grid--3,
  .grid--4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 599px) {
  .grid--2,
  .grid--3,
  .grid--4 {
    grid-template-columns: 1fr;
  }
}

.display-title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: clamp(38px, 6vw, 68px);
  line-height: 1.08;
  letter-spacing: -0.01em;
  color: var(--text-primary);
  transform: skewX(-3deg);
  transform-origin: left;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 28px;
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.05em;
  text-decoration: none;
  color: var(--text-primary);
  background: var(--surface-muted);
  border: 1px solid var(--border-soft);
  cursor: pointer;
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
  transition: background 0.25s ease, color 0.25s ease, border-color 0.25s ease, transform 0.25s var(--ease-out);
}

.btn:hover,
.btn:focus-visible {
  color: var(--text-primary);
  border-color: var(--accent-neon);
  transform: translateY(-2px);
}

.btn--primary {
  background: var(--accent-neon);
  border-color: transparent;
  color: var(--bg-deep);
}

.btn--primary:hover,
.btn--primary:focus-visible {
  background: var(--accent-orange);
  border-color: transparent;
  color: var(--bg-deep);
}

.btn--ghost {
  background: transparent;
  border-color: rgba(242, 244, 248, 0.35);
  color: var(--text-secondary);
}

.btn--ghost:hover,
.btn--ghost:focus-visible {
  border-color: var(--accent-neon);
  color: var(--accent-neon);
}

.btn--sm {
  padding: 9px 18px;
  font-size: 13px;
  clip-path: polygon(0 0, calc(100% - 9px) 0, 100% 9px, 100% 100%, 9px 100%, 0 calc(100% - 9px));
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent-orange);
  background: rgba(255, 122, 0, 0.08);
  border: 1px solid rgba(255, 122, 0, 0.35);
  clip-path: polygon(0 0, calc(100% - 8px) 0, 100% 8px, 100% 100%, 0 100%);
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--surface-muted);
  border: 1px solid var(--border-soft);
  border-radius: 999px;
  text-decoration: none;
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.chip:hover,
.chip:focus-visible {
  color: var(--accent-neon);
  border-color: var(--accent-neon);
  background: rgba(42, 245, 152, 0.07);
}

.section-number {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent-neon);
}

.section-number::before {
  content: '';
  width: 32px;
  height: 2px;
  background: var(--accent-neon);
  transform: skewX(-32deg);
}

.chapter-head {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 20px;
  align-items: start;
  margin-bottom: 32px;
}

.chapter-head__num {
  font-family: var(--font-mono);
  font-size: clamp(44px, 6vw, 72px);
  font-weight: 700;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px var(--accent-neon);
  opacity: 0.45;
  transform: skewX(-8deg);
  user-select: none;
}

.chapter-head__title {
  font-family: var(--font-heading);
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.3;
  padding-top: 4px;
}

.chapter-head__desc {
  margin-top: 10px;
  font-size: 14px;
  color: var(--text-secondary);
  max-width: 60ch;
}

.panel {
  position: relative;
  padding: 28px;
  background: var(--bg-card);
  border: 1px solid var(--border-soft);
  transition: border-color 0.3s ease, transform 0.3s var(--ease-out);
}

.panel:hover,
.panel:focus-within {
  border-color: rgba(42, 245, 152, 0.5);
  transform: translateY(-4px);
}

.panel--cut {
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 0 100%);
}

.panel--paper {
  background:
    linear-gradient(135deg, var(--overlay-light), transparent 38%),
    var(--bg-card);
}

.prose {
  max-width: 76ch;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-secondary);
}

.prose h1,
.prose h2,
.prose h3 {
  font-family: var(--font-heading);
  color: var(--text-primary);
  line-height: 1.25;
}

.prose h1 {
  margin: 40px 0 16px;
  font-size: clamp(30px, 4vw, 44px);
}

.prose h2 {
  position: relative;
  margin: 40px 0 14px;
  padding-left: 16px;
  font-size: 26px;
}

.prose h2::before {
  content: '';
  position: absolute;
  left: 0;
  top: 6px;
  bottom: 6px;
  width: 4px;
  background: linear-gradient(180deg, var(--accent-neon), var(--accent-orange));
  transform: skewX(-14deg);
}

.prose h3 {
  margin: 28px 0 10px;
  font-size: 20px;
}

.prose p {
  margin-bottom: 20px;
}

.prose ul,
.prose ol {
  margin: 0 0 20px;
  padding-left: 24px;
}

.prose li {
  margin-bottom: 8px;
}

.prose li::marker {
  color: var(--accent-neon);
}

.prose blockquote {
  margin: 32px 0;
  padding: 20px 24px;
  background: var(--surface-muted);
  border-left: 4px solid var(--accent-orange);
  color: var(--text-primary);
  font-size: 18px;
}

.prose a {
  color: var(--accent-neon);
}

.prose a:hover {
  color: var(--accent-orange);
}

.prose strong {
  color: var(--text-primary);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  margin-bottom: 32px;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--text-secondary);
}

.breadcrumb li {
  display: inline-flex;
  align-items: center;
}

.breadcrumb li + li::before {
  content: '/';
  margin-inline: 10px;
  color: var(--accent-orange);
}

.breadcrumb a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
}

.breadcrumb a:hover,
.breadcrumb a:focus-visible {
  color: var(--accent-neon);
}

.breadcrumb [aria-current='page'] {
  color: var(--text-primary);
}

.img-frame {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background:
    linear-gradient(135deg, var(--surface-muted), var(--bg-card));
  border: 1px solid var(--border-soft);
}

.img-frame::before {
  content: 'IMG';
  position: absolute;
  right: 16px;
  bottom: 14px;
  z-index: 2;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.2em;
  color: var(--text-secondary);
  opacity: 0.8;
}

.img-frame::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent-neon), var(--accent-orange));
  transform: skewY(-0.6deg);
  transform-origin: left bottom;
}

.img-frame--wide {
  aspect-ratio: 21 / 9;
}

.img-frame--portrait {
  aspect-ratio: 3 / 4;
}

.img-frame--skew {
  clip-path: polygon(0 0, calc(100% - 32px) 0, 100% 32px, 100% 100%, 0 100%);
}

.js-enabled [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.6s ease, transform 0.6s var(--ease-out);
}

.js-enabled [data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 1180px) {
  .masthead__label {
    padding: 5px 8px;
    font-size: 10px;
    letter-spacing: 0.08em;
  }
}

@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;
  }

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

  .scroll-progress {
    display: none;
  }
}