:root {
  --color-primary: #0A1B3D;
  --color-secondary: #12294D;
  --color-accent: #FF5A3C;
  --color-gold: #F0A202;
  --color-cream: #F5F0E6;
  --color-ink: #1A1A1A;
  --color-white: #FFFFFF;
  --color-cyan: #00E5FF;
  --color-grid: #33415C;
  --font-headline: system-ui, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "Roboto Mono", Consolas, monospace;
  --header-h: 72px;
  --container-w: 1280px;
  --container-pad: clamp(1rem, 4vw, 2.5rem);
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 2rem;
  --space-lg: 4rem;
  --space-xl: 7rem;
  --radius: 8px;
  --radius-lg: 12px;
}

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

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

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.75;
  color: var(--color-cream);
  background-color: var(--color-primary);
  background-image:
    linear-gradient(rgba(0, 229, 255, 0.022) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 255, 0.022) 1px, transparent 1px);
  background-size: 72px 72px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-headline);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--color-white);
}

h1 {
  font-size: clamp(2.5rem, 6vw, 4rem);
}

h2 {
  font-size: clamp(2rem, 4vw, 2.8rem);
}

h3 {
  font-size: 1.5rem;
}

p {
  margin: 0;
}

ul,
ol {
  list-style: none;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease;
}

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

button,
input,
select,
textarea {
  font: inherit;
  color: inherit;
  background: none;
  border: none;
  border-radius: 0;
}

button {
  cursor: pointer;
}

:focus-visible {
  outline: 2px solid var(--color-cyan);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection {
  background: var(--color-accent);
  color: var(--color-white);
}

.skip-link {
  position: fixed;
  top: -72px;
  left: 1rem;
  z-index: 2000;
  display: inline-block;
  padding: 0.7rem 1.4rem;
  background: var(--color-accent);
  color: var(--color-white);
  font-size: 0.9rem;
  font-weight: 700;
  border-radius: 0 0 var(--radius) var(--radius);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
  transition: top 0.3s ease;
}

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

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-h);
  background: transparent;
  border-bottom: 1px solid transparent;
  transition:
    background-color 0.4s ease,
    border-color 0.4s ease,
    box-shadow 0.4s ease,
    -webkit-backdrop-filter 0.4s ease,
    backdrop-filter 0.4s ease;
}

.site-header[data-scrolled="true"] {
  background-color: rgba(10, 27, 61, 0.92);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  border-bottom-color: rgba(0, 229, 255, 0.15);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.35);
}

.site-header[data-nav-open="true"] {
  background-color: var(--color-primary);
  border-bottom-color: rgba(0, 229, 255, 0.15);
}

.header-inner {
  height: 100%;
  max-width: var(--container-w);
  margin: 0 auto;
  padding: 0 var(--container-pad);
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 1.5rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  flex-shrink: 0;
}

.brand-mark {
  position: relative;
  width: 34px;
  height: 34px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  border: 1px solid rgba(0, 229, 255, 0.55);
  border-radius: 50%;
}

.brand-mark::before,
.brand-mark::after {
  content: "";
  position: absolute;
  background: rgba(0, 229, 255, 0.32);
  pointer-events: none;
}

.brand-mark::before {
  top: 50%;
  left: -4px;
  right: -4px;
  height: 1px;
}

.brand-mark::after {
  left: 50%;
  top: -4px;
  bottom: -4px;
  width: 1px;
}

.brand-dot {
  position: relative;
  z-index: 1;
  width: 8px;
  height: 8px;
  background: var(--color-accent);
  border-radius: 50%;
  animation: brand-pulse 2.4s ease-out infinite;
}

@keyframes brand-pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(255, 90, 60, 0.5);
  }
  70% {
    box-shadow: 0 0 0 12px rgba(255, 90, 60, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(255, 90, 60, 0);
  }
}

.brand-name {
  font-family: var(--font-headline);
  font-size: 1.35rem;
  font-weight: 800;
  line-height: 1;
  letter-spacing: 0.1em;
  color: var(--color-white);
  white-space: nowrap;
}

.header-coord {
  justify-self: center;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: rgba(245, 240, 230, 0.38);
  white-space: nowrap;
  text-transform: uppercase;
}

.header-coord__live {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-accent);
  animation: live-blink 2s ease-in-out infinite;
}

@keyframes live-blink {
  0%,
  100% {
    opacity: 1;
    box-shadow: 0 0 8px rgba(255, 90, 60, 0.8);
  }
  50% {
    opacity: 0.35;
    box-shadow: 0 0 0 rgba(255, 90, 60, 0);
  }
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 10px;
  transition: background-color 0.25s ease, border-color 0.25s ease, transform 0.15s ease;
}

.nav-toggle:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(0, 229, 255, 0.4);
}

.nav-toggle:active {
  transform: scale(0.95);
}

.nav-toggle__bar {
  width: 20px;
  height: 2px;
  background: var(--color-white);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.2s 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 {
  justify-self: end;
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: 0.15rem;
}

.site-nav__item {
  display: inline-flex;
}

.site-nav__link {
  display: inline-flex;
  align-items: baseline;
  position: relative;
  padding: 0.5rem 0.75rem;
  font-size: 0.92rem;
  font-weight: 600;
  color: rgba(245, 240, 230, 0.72);
  border-radius: 4px;
  white-space: nowrap;
  transition: color 0.25s ease, background-color 0.25s ease;
}

.site-nav__num {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  color: var(--color-accent);
  margin-right: 0.35rem;
  opacity: 0.85;
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: 0.75rem;
  right: 0.75rem;
  bottom: 0.3rem;
  height: 2px;
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.3s ease;
}

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

.site-nav__link:hover::after {
  transform: scaleX(1);
}

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

.site-nav__link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--color-cyan);
}

.scroll-progress {
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--color-accent), var(--color-cyan));
  transform: scaleX(0);
  transform-origin: left center;
  pointer-events: none;
}

.back-to-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  z-index: 990;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background: var(--color-secondary);
  border: 1px solid rgba(0, 229, 255, 0.3);
  border-radius: 50%;
  color: var(--color-cyan);
  font-size: 1.1rem;
  box-shadow: 0 10px 28px rgba(0, 0, 0, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition:
    opacity 0.25s ease,
    transform 0.25s ease,
    visibility 0s linear 0.25s,
    background-color 0.25s ease,
    border-color 0.25s ease,
    color 0.25s ease;
}

.back-to-top[data-visible="true"] {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  transition:
    opacity 0.25s ease,
    transform 0.25s ease,
    visibility 0s,
    background-color 0.25s ease,
    border-color 0.25s ease,
    color 0.25s ease;
}

.back-to-top:hover,
.back-to-top:focus-visible {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-white);
}

.back-to-top__icon {
  line-height: 1;
}

.site-footer {
  position: relative;
  flex-shrink: 0;
  background-color: var(--color-primary);
  background-image:
    linear-gradient(rgba(0, 229, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 255, 0.03) 1px, transparent 1px);
  background-size: 72px 72px;
  border-top: 1px solid rgba(0, 229, 255, 0.12);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(
    90deg,
    var(--color-accent) 0,
    var(--color-accent) 140px,
    rgba(245, 240, 230, 0.14) 140px,
    rgba(245, 240, 230, 0.14) calc(100% - 220px),
    var(--color-cyan) calc(100% - 220px),
    var(--color-cyan) 100%
  );
}

.footer-grid {
  max-width: var(--container-w);
  margin: 0 auto;
  padding: var(--space-lg) var(--container-pad) var(--space-md);
  display: grid;
  grid-template-columns: 1.3fr 1fr 1.2fr;
  gap: var(--space-lg);
  position: relative;
}

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

.footer-col--brand {
  padding-right: 1rem;
}

.footer-brand-name {
  display: inline-block;
  font-family: var(--font-headline);
  font-size: 1.75rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--color-white);
  margin-bottom: 0.85rem;
}

.footer-brand-name::after {
  content: "";
  display: block;
  width: 36px;
  height: 3px;
  background: var(--color-accent);
  margin-top: 10px;
}

.footer-slogan {
  font-family: var(--font-headline);
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--color-cyan);
  margin-bottom: 0.9rem;
}

.footer-trust {
  max-width: 28rem;
  font-size: 0.85rem;
  line-height: 1.85;
  color: rgba(245, 240, 230, 0.5);
}

.footer-heading {
  font-family: var(--font-body);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.22em;
  color: rgba(245, 240, 230, 0.35);
  margin-bottom: 1.1rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  text-transform: uppercase;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.35rem 0.5rem;
}

.footer-links a {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0;
  font-size: 0.9rem;
  color: rgba(245, 240, 230, 0.68);
  transition: color 0.2s ease;
}

.footer-links a::before {
  content: "";
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: currentColor;
  opacity: 0.35;
  margin-right: 0.55rem;
  flex-shrink: 0;
  transition: opacity 0.2s ease, background-color 0.2s ease;
}

.footer-links a:hover {
  color: var(--color-white);
}

.footer-links a:hover::before {
  background: var(--color-accent);
  opacity: 1;
}

.footer-contact li {
  padding: 0.6rem 0;
  border-bottom: 1px dashed rgba(255, 255, 255, 0.1);
}

.footer-contact li:last-child {
  border-bottom: none;
}

.footer-contact__label {
  display: block;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--color-cyan);
  margin-bottom: 0.2rem;
  text-transform: uppercase;
}

.footer-contact__value {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.92rem;
  line-height: 1.5;
  color: rgba(245, 240, 230, 0.8);
  word-break: break-all;
}

.footer-bottom {
  max-width: var(--container-w);
  margin: 0 auto;
  padding: 1.25rem var(--container-pad) 2.25rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.07);
}

.footer-copy,
.footer-icp {
  font-size: 0.8rem;
  color: rgba(245, 240, 230, 0.4);
}

.footer-icp {
  font-family: var(--font-mono);
}

#main-content {
  position: relative;
  flex: 1 0 auto;
  min-height: 60vh;
  scroll-margin-top: var(--header-h);
  outline: none;
}

.site-container {
  max-width: var(--container-w);
  margin: 0 auto;
  padding-left: var(--container-pad);
  padding-right: var(--container-pad);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  padding: 0.8rem 1.7rem;
  font-family: var(--font-body);
  font-size: 0.94rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-white);
  background: var(--color-accent);
  border: 1px solid var(--color-accent);
  border-radius: var(--radius);
  position: relative;
  overflow: hidden;
  transition:
    background-color 0.25s ease,
    border-color 0.25s ease,
    box-shadow 0.25s ease,
    transform 0.15s ease;
}

.btn:hover {
  background: #ff6a4d;
  border-color: #ff6a4d;
  box-shadow: 0 10px 28px rgba(255, 90, 60, 0.35);
  transform: translateY(-2px);
}

.btn:active {
  transform: translateY(0) scale(0.97);
}

.btn--ghost {
  background: transparent;
  border-color: rgba(0, 229, 255, 0.45);
  color: var(--color-cyan);
  box-shadow: none;
}

.btn--ghost:hover {
  background: rgba(0, 229, 255, 0.1);
  border-color: var(--color-cyan);
  color: var(--color-white);
  box-shadow: none;
}

.btn--dark {
  background: var(--color-secondary);
  border-color: rgba(255, 255, 255, 0.16);
  color: var(--color-white);
  box-shadow: none;
}

.btn--dark:hover {
  background: var(--color-primary);
  border-color: rgba(255, 255, 255, 0.3);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem;
  padding: 0.75rem 0;
  font-size: 0.82rem;
  color: rgba(245, 240, 230, 0.45);
}

.breadcrumb a {
  color: rgba(245, 240, 230, 0.7);
  transition: color 0.2s ease;
}

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

.breadcrumb__sep {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  opacity: 0.5;
}

.breadcrumb [aria-current="page"] {
  color: var(--color-cyan);
  font-weight: 600;
}

.grid {
  display: grid;
  gap: var(--space-md);
}

.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 {
  position: relative;
  padding: 1.5rem;
  background: var(--color-secondary);
  border: 1px solid var(--color-grid);
  border-radius: var(--radius-lg);
  transition:
    border-color 0.3s ease,
    transform 0.3s ease,
    box-shadow 0.3s ease;
}

.card:hover {
  border-color: rgba(0, 229, 255, 0.3);
  box-shadow: 0 14px 36px rgba(0, 0, 0, 0.35);
  transform: translateY(-4px);
}

.card__index {
  position: absolute;
  top: 0.9rem;
  right: 1rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: rgba(0, 229, 255, 0.6);
}

.card__title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: 0.5rem;
}

.card__text {
  font-size: 0.9rem;
  line-height: 1.7;
  color: rgba(245, 240, 230, 0.6);
}

.chapter {
  position: relative;
  padding: var(--space-xl) 0;
}

.chapter::before {
  content: attr(data-chapter);
  position: absolute;
  top: var(--space-lg);
  right: 0;
  font-family: var(--font-mono);
  font-size: clamp(3.5rem, 9vw, 7rem);
  font-weight: 700;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px rgba(0, 229, 255, 0.18);
  z-index: 0;
  pointer-events: none;
  user-select: none;
}

.chapter > * {
  position: relative;
  z-index: 1;
}

.chapter__label {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--color-accent);
  margin-bottom: 0.65rem;
  text-transform: uppercase;
}

.chapter__label::before {
  content: "";
  width: 32px;
  height: 1px;
  background: var(--color-accent);
}

.chapter__title {
  font-size: clamp(1.75rem, 4vw, 2.6rem);
  font-weight: 800;
  line-height: 1.15;
  color: var(--color-white);
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}

.chapter__lead {
  max-width: 36rem;
  font-size: 0.98rem;
  line-height: 1.8;
  color: rgba(245, 240, 230, 0.62);
}

.media {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: var(--color-secondary);
  border: 1px solid var(--color-grid);
  border-radius: var(--radius);
}

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

.media--square {
  aspect-ratio: 1 / 1;
}

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

.media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.media:hover img {
  transform: scale(1.04);
}

.media--placeholder {
  background-color: var(--color-secondary);
  background-image:
    linear-gradient(rgba(0, 229, 255, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 255, 0.06) 1px, transparent 1px);
  background-size: 28px 28px;
}

.media--placeholder::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 30% 40%, rgba(0, 229, 255, 0.12), transparent 55%),
    radial-gradient(circle at 75% 70%, rgba(255, 90, 60, 0.1), transparent 45%);
  pointer-events: none;
}

.page-hero {
  position: relative;
  padding-top: calc(var(--header-h) + var(--space-lg));
  padding-bottom: var(--space-lg);
  background: var(--color-primary);
  border-bottom: 1px solid rgba(0, 229, 255, 0.1);
  overflow: hidden;
}

.page-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0, 229, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 255, 0.05) 1px, transparent 1px);
  background-size: 64px 64px;
  pointer-events: none;
  -webkit-mask-image: linear-gradient(to bottom, #000 0%, transparent 85%);
  mask-image: linear-gradient(to bottom, #000 0%, transparent 85%);
}

.page-hero__container {
  position: relative;
  max-width: var(--container-w);
  margin: 0 auto;
  padding-left: var(--container-pad);
  padding-right: var(--container-pad);
}

.page-hero__meta {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  color: var(--color-accent);
  margin-bottom: 0.75rem;
}

.page-hero__meta::before {
  content: "";
  width: 28px;
  height: 1px;
  background: var(--color-accent);
}

.page-hero__title {
  font-size: clamp(2.2rem, 5vw, 3.4rem);
  margin-bottom: 0.75rem;
}

.page-hero__lead {
  max-width: 38rem;
  font-size: 1rem;
  line-height: 1.8;
  color: rgba(245, 240, 230, 0.62);
}

.grid-bg {
  position: relative;
  background-image:
    linear-gradient(rgba(0, 229, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 255, 0.05) 1px, transparent 1px);
  background-size: 64px 64px;
}

.coord-label {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: rgba(0, 229, 255, 0.6);
  text-transform: uppercase;
}

.coord-label::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--color-accent);
}

.note-vertical {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  font-size: 0.74rem;
  letter-spacing: 0.24em;
  color: rgba(245, 240, 230, 0.35);
}

.data-text {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  color: var(--color-cyan);
}

@media (max-width: 1160px) {
  .header-coord {
    display: none;
  }
}

@media (max-width: 1020px) {
  .grid--4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .grid--3 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 960px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-md);
    padding-top: var(--space-lg);
  }

  .footer-col--brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 900px) {
  .header-inner {
    display: flex;
    justify-content: space-between;
    gap: 1rem;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    z-index: 999;
    max-height: 0;
    overflow: hidden;
    background: var(--color-primary);
    box-shadow: 0 24px 48px rgba(0, 0, 0, 0.45);
    visibility: hidden;
    opacity: 0;
    transform: translateY(-10px);
    transition:
      opacity 0.3s ease,
      transform 0.3s ease,
      visibility 0s linear 0.35s,
      max-height 0.35s ease;
  }

  .site-nav[data-open="true"] {
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
    visibility: visible;
    opacity: 1;
    transform: translateY(0);
    transition:
      opacity 0.3s ease,
      transform 0.3s ease,
      visibility 0s,
      max-height 0.35s ease;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    padding: 1rem;
    gap: 0.25rem;
  }

  .site-nav__link {
    display: flex;
    align-items: center;
    padding: 0.85rem 1rem;
    font-size: 0.98rem;
    border-left: 3px solid transparent;
    border-radius: 0;
  }

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

  .site-nav__link[aria-current="page"] {
    background: rgba(0, 229, 255, 0.07);
    border-left-color: var(--color-cyan);
  }
}

@media (max-width: 640px) {
  :root {
    --header-h: 64px;
  }
}

@media (max-width: 620px) {
  .grid--2,
  .grid--3,
  .grid--4 {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 560px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }

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

  .back-to-top {
    right: 1rem;
    bottom: 1rem;
    width: 44px;
    height: 44px;
  }
}

@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;
    scroll-behavior: auto !important;
  }
}