:root {
  --lb-primary: #0B3D2E;
  --lb-primary-deep: #07281E;
  --lb-primary-mid: #116B4E;
  --lb-accent: #FF6B35;
  --lb-accent-light: #FFD166;
  --lb-bg: #F2F2F2;
  --lb-text: #1A1A1A;
  --lb-text-muted: #66736C;
  --lb-border: #E0E0E0;
  --lb-white: #FFFFFF;
  --lb-cyan: #00C8C8;

  --lb-font-heading: 'Anton', 'Impact', 'Arial Black', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --lb-font-body: 'Inter', -apple-system, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --lb-font-mono: 'JetBrains Mono', 'SFMono-Regular', 'Liberation Mono', Consolas, 'PingFang SC', monospace;

  --lb-rail-width: 96px;
  --lb-header-height: 72px;
  --lb-max-width: 1440px;
  --lb-content-gutter: 32px;
  --lb-section-y: clamp(48px, 8vw, 96px);
}

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

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

body {
  font-family: var(--lb-font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--lb-text);
  background: var(--lb-bg);
  padding-left: var(--lb-rail-width);
}

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

button {
  font-family: inherit;
  font-size: inherit;
  cursor: pointer;
}

a,
button {
  outline: none;
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--lb-accent);
  outline-offset: 3px;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--lb-font-heading);
  font-weight: 600;
  line-height: 1.12;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--lb-primary);
}

h1 {
  font-size: clamp(2.75rem, 7vw, 5.25rem);
}

h2 {
  font-size: clamp(2rem, 4.5vw, 3.25rem);
}

h3 {
  font-size: 1.5rem;
}

h4 {
  font-size: 1.125rem;
}

p {
  margin-bottom: 1em;
}

#main-content {
  scroll-margin-top: calc(var(--lb-header-height) + 16px);
  min-height: 60vh;
}

.container {
  width: 100%;
  max-width: var(--lb-max-width);
  margin: 0 auto;
  padding: 0 var(--lb-content-gutter);
}

.section {
  padding: var(--lb-section-y) 0;
}

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

.section--dark h1,
.section--dark h2,
.section--dark h3,
.section--dark h4 {
  color: var(--lb-white);
}

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

.section__kicker {
  display: block;
  font-family: var(--lb-font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--lb-accent);
  margin-bottom: 10px;
}

.section__title {
  margin-bottom: 12px;
}

.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));
}

.card {
  background: var(--lb-white);
  border: 1px solid var(--lb-border);
  border-radius: 4px;
  padding: 24px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(11, 61, 46, 0.08);
}

.card__title {
  margin-bottom: 8px;
}

.card__desc {
  color: var(--lb-text-muted);
  font-size: 0.9375rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--lb-font-body);
  font-weight: 600;
  font-size: 0.9375rem;
  line-height: 1;
  padding: 13px 26px;
  border-radius: 2px;
  text-decoration: none;
  border: 2px solid transparent;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

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

.btn--primary:hover {
  background: #E85A2A;
}

.btn--ghost {
  background: transparent;
  border-color: rgba(255, 255, 255, 0.45);
  color: var(--lb-white);
}

.btn--ghost:hover {
  border-color: var(--lb-white);
  background: rgba(255, 255, 255, 0.08);
}

.btn--outline {
  background: transparent;
  border-color: var(--lb-accent);
  color: var(--lb-accent);
}

.btn--outline:hover {
  background: var(--lb-accent);
  color: var(--lb-white);
}

.breadcrumb {
  padding: 16px 0;
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px;
  list-style: none;
  font-size: 0.875rem;
}

.breadcrumb__item {
  color: var(--lb-text-muted);
}

.breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  margin: 0 8px;
  color: var(--lb-border);
}

.breadcrumb__link {
  color: var(--lb-primary);
  text-decoration: none;
}

.breadcrumb__link:hover {
  color: var(--lb-accent);
}

.breadcrumb__current {
  color: var(--lb-text-muted);
}

.kicker {
  display: block;
  font-family: var(--lb-font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--lb-accent);
}

.chapter {
  display: grid;
  grid-template-columns: minmax(100px, 140px) 1fr;
  gap: 16px 32px;
  padding: 28px 0;
  border-bottom: 1px solid var(--lb-border);
}

.chapter__index {
  font-family: var(--lb-font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.14em;
  color: var(--lb-accent);
  text-transform: uppercase;
  line-height: 1.8;
}

.chapter__body h3 {
  margin-bottom: 8px;
}

.block {
  padding: 24px 28px;
  border-radius: 4px;
}

.block--green {
  background: var(--lb-primary);
  color: var(--lb-white);
}

.block--orange {
  background: var(--lb-accent);
  color: var(--lb-white);
}

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

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

.num {
  font-family: var(--lb-font-mono);
  font-weight: 500;
  letter-spacing: -0.02em;
}

.skip-link {
  position: fixed;
  left: 16px;
  top: 16px;
  z-index: 3000;
  transform: translateY(-220%);
  background: var(--lb-accent);
  color: var(--lb-white);
  font-family: var(--lb-font-body);
  font-weight: 600;
  font-size: 0.875rem;
  padding: 10px 18px;
  border-radius: 2px;
  text-decoration: none;
  transition: transform 0.2s ease;
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 800;
  height: var(--lb-header-height);
  background: linear-gradient(135deg, var(--lb-primary-deep) 0%, var(--lb-primary) 60%);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.site-header__inner {
  max-width: var(--lb-max-width);
  height: 100%;
  margin: 0 auto;
  padding: 0 var(--lb-content-gutter);
  display: flex;
  align-items: center;
  gap: 24px;
}

.site-brand {
  font-family: var(--lb-font-heading);
  font-size: 1.6rem;
  letter-spacing: 0.06em;
  color: var(--lb-white);
  text-decoration: none;
  text-transform: uppercase;
  line-height: 1;
  white-space: nowrap;
}

.site-brand b {
  color: var(--lb-accent);
  font-weight: 400;
}

.site-header__notice {
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.78);
  text-decoration: none;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  padding: 7px 13px;
  border-radius: 2px;
  transition: background 0.2s ease, border-color 0.2s ease;
}

.site-header__notice:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.28);
}

.site-header__notice-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--lb-accent);
  box-shadow: 0 0 0 0 rgba(255, 107, 53, 0.6);
  animation: lb-pulse-dot 2s infinite;
}

@keyframes lb-pulse-dot {
  0% {
    box-shadow: 0 0 0 0 rgba(255, 107, 53, 0.6);
  }
  70% {
    box-shadow: 0 0 0 8px rgba(255, 107, 53, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(255, 107, 53, 0);
  }
}

.site-header__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  background: transparent;
  border: none;
}

.site-header__toggle-bar {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--lb-white);
  transition: transform 0.3s ease, opacity 0.3s ease;
}

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

.site-header__toggle[aria-expanded="true"] .site-header__toggle-bar:nth-child(2) {
  opacity: 0;
}

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

.site-track {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--lb-rail-width);
  height: 100vh;
  height: 100dvh;
  z-index: 1000;
  background: linear-gradient(180deg, var(--lb-primary) 0%, var(--lb-primary-deep) 100%);
  border-right: 1px solid rgba(255, 255, 255, 0.08);
  display: flex;
  flex-direction: column;
  align-items: stretch;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.site-track:focus {
  outline: none;
}

.site-track__head {
  display: none;
  justify-content: space-between;
  align-items: center;
  padding: 14px 10px 14px 16px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.site-track__label {
  font-family: var(--lb-font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.55);
}

.site-track__close {
  width: 40px;
  height: 40px;
  border: none;
  background: transparent;
  color: var(--lb-white);
  font-size: 1.375rem;
  line-height: 1;
  border-radius: 2px;
}

.site-track__close:hover {
  background: rgba(255, 255, 255, 0.08);
}

.site-track__list {
  list-style: none;
  display: flex;
  flex-direction: column;
  flex: 1;
  justify-content: center;
  margin: 0;
  padding: 0;
}

.site-track__item {
  margin: 2px 0;
}

.site-track__link {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 5px;
  padding: 12px 4px;
  color: rgba(255, 255, 255, 0.65);
  text-decoration: none;
  transition: color 0.2s ease, background 0.2s ease;
}

.site-track__link::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 3px;
  height: 0;
  background: var(--lb-accent);
  transition: height 0.3s ease;
}

.site-track__link:hover {
  color: var(--lb-white);
}

.site-track__link:hover::before,
.site-track__link[aria-current="page"]::before {
  height: 34px;
}

.site-track__link[aria-current="page"] {
  color: var(--lb-white);
}

.site-track__index {
  font-family: var(--lb-font-mono);
  font-size: 0.6875rem;
  color: var(--lb-accent);
  letter-spacing: 0.05em;
}

.site-track__text {
  font-size: 0.8125rem;
  letter-spacing: 0.06em;
}

.site-track__foot {
  padding: 16px 0;
  display: flex;
  justify-content: center;
}

.site-track__mark {
  font-family: var(--lb-font-heading);
  font-size: 1.25rem;
  color: rgba(255, 255, 255, 0.2);
  letter-spacing: 0.1em;
}

.site-footer {
  background: linear-gradient(150deg, var(--lb-primary) 0%, var(--lb-primary-deep) 80%);
  color: rgba(255, 255, 255, 0.75);
  margin-top: 80px;
}

.site-footer a {
  color: rgba(255, 255, 255, 0.68);
  text-decoration: none;
  transition: color 0.2s ease;
}

.site-footer a:hover {
  color: var(--lb-accent);
}

.site-footer__top {
  max-width: var(--lb-max-width);
  margin: 0 auto;
  padding: 64px var(--lb-content-gutter) 48px;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 40px;
}

.site-footer__logo {
  display: inline-block;
  font-family: var(--lb-font-heading);
  font-size: 1.75rem;
  letter-spacing: 0.06em;
  color: var(--lb-white);
  text-decoration: none;
  text-transform: uppercase;
  line-height: 1.1;
}

.site-footer__logo b {
  color: var(--lb-accent);
  font-weight: 400;
}

.site-footer__logo:hover {
  color: var(--lb-white);
}

.site-footer__tagline {
  color: rgba(255, 255, 255, 0.52);
  font-size: 0.9375rem;
  line-height: 1.7;
  max-width: 320px;
  margin-top: 14px;
  margin-bottom: 0;
}

.site-footer__section {
  min-width: 0;
}

.site-footer__title {
  font-family: var(--lb-font-heading);
  font-size: 0.9375rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--lb-white);
  margin-bottom: 16px;
  padding-bottom: 8px;
  position: relative;
}

.site-footer__title::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 24px;
  height: 2px;
  background: var(--lb-accent);
}

.site-footer__links,
.site-footer__contacts {
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-footer__links li,
.site-footer__contacts li {
  margin-bottom: 8px;
}

.site-footer__contacts li {
  display: flex;
  gap: 8px;
  font-size: 0.875rem;
  line-height: 1.6;
}

.site-footer__label {
  flex: 0 0 auto;
  display: inline-block;
  min-width: 38px;
  font-family: var(--lb-font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--lb-accent-light);
  padding-top: 2px;
}

.site-footer__value {
  color: rgba(255, 255, 255, 0.72);
  overflow-wrap: anywhere;
}

.site-footer__bottom {
  max-width: var(--lb-max-width);
  margin: 0 auto;
  padding: 18px var(--lb-content-gutter);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.site-footer__copyright,
.site-footer__icp,
.site-footer__service {
  margin: 0;
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.5);
}

.site-footer__domain {
  font-family: var(--lb-font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.02em;
}

.site-footer__icp a {
  color: rgba(255, 255, 255, 0.5);
}

.site-footer__icp a:hover {
  color: var(--lb-accent);
}

.site-footer__service {
  flex-basis: 100%;
  color: rgba(255, 255, 255, 0.35);
  font-size: 0.75rem;
}

.img-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: linear-gradient(135deg, var(--lb-primary-mid), var(--lb-primary));
  border-radius: 4px;
}

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

.img-frame--square {
  aspect-ratio: 1 / 1;
}

.img-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.img-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 55%, rgba(7, 40, 30, 0.55));
  pointer-events: none;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0;
  height: 3px;
  background: var(--lb-accent);
  z-index: 3000;
  pointer-events: none;
}

[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

@media (max-width: 991px) {
  body {
    padding-left: 0;
  }

  .site-header__toggle {
    display: flex;
  }

  .site-header__notice {
    margin-left: auto;
  }

  .site-track {
    width: min(320px, 85vw);
    transform: translateX(-100%);
    box-shadow: none;
  }

  .site-track[data-open="true"] {
    transform: translateX(0);
    box-shadow: 10px 0 36px rgba(7, 40, 30, 0.35);
  }

  .site-track__head {
    display: flex;
  }

  .site-track__list {
    justify-content: flex-start;
    padding-top: 24px;
    flex: 1;
  }

  .site-track__item {
    margin: 0;
  }

  .site-track__link {
    flex-direction: row;
    justify-content: flex-start;
    gap: 14px;
    padding: 15px 24px;
  }

  .site-track__link::before {
    left: 0;
    top: 0;
    transform: none;
    width: 3px;
    height: 0;
  }

  .site-track__link:hover::before,
  .site-track__link[aria-current="page"]::before {
    height: 100%;
  }

  .site-track__text {
    font-size: 0.9375rem;
  }

  .site-track__foot {
    padding: 18px 24px;
    justify-content: flex-end;
  }

  .site-track__mark {
    font-size: 0.9375rem;
  }

  body.nav-open {
    overflow: hidden;
  }

  .site-footer__top {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    padding: 48px var(--lb-content-gutter) 32px;
  }
}

@media (max-width: 767px) {
  :root {
    --lb-content-gutter: 20px;
    --lb-header-height: 64px;
  }

  .site-header__notice {
    width: 40px;
    height: 40px;
    padding: 0;
    border-radius: 50%;
    justify-content: center;
    border: none;
    background: rgba(255, 255, 255, 0.1);
  }

  .site-header__notice-text {
    display: none;
  }

  .site-header__toggle {
    width: 40px;
    height: 40px;
    margin-left: 4px;
  }

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

  .chapter {
    grid-template-columns: 1fr;
    gap: 4px 0;
    padding: 20px 0;
  }

  .site-footer__top {
    grid-template-columns: 1fr;
    gap: 28px;
    padding: 40px var(--lb-content-gutter) 28px;
  }

  .site-footer__bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .site-footer__service {
    flex-basis: auto;
  }
}

@media (min-width: 992px) {
  .site-track {
    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;
  }

  [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .site-track {
    transition: none;
  }
}