:root {
  --color-primary-bg: #0A1F44;
  --color-secondary-bg: #1B2A4A;
  --color-accent-red: #E63946;
  --color-accent-gold: #F4A261;
  --color-text-white: #FFFFFF;
  --color-text-light: #B0C4DE;
  --color-data-font: #00FFC6;
  --color-link-hover: #FF6B6B;
  --color-border-line: #2A3F66;
  --font-headings: 'Inter', 'Helvetica Neue', Arial, sans-serif;
  --font-body: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-data: 'JetBrains Mono', 'Courier New', monospace;
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 2rem;
  --spacing-xl: 4rem;
  --container-max: 1200px;
  --header-height: 72px;
  --transition-base: 0.25s ease;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-body);
  background-color: var(--color-primary-bg);
  color: var(--color-text-white);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-base);
}

a:hover,
a:focus-visible {
  color: var(--color-link-hover);
}

ul, ol {
  list-style: none;
}

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

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

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

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  html {
    scroll-behavior: auto;
  }
}

.skip-link {
  position: absolute;
  top: -100%;
  left: var(--spacing-md);
  z-index: 1000;
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-accent-red);
  color: var(--color-text-white);
  font-family: var(--font-headings);
  font-weight: 700;
  font-size: 0.875rem;
  border-radius: 0 0 4px 4px;
  transition: top 0.2s ease;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 900;
  background: var(--color-primary-bg);
  border-bottom: 1px solid var(--color-border-line);
  overflow: hidden;
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  height: var(--header-height);
  position: relative;
  z-index: 2;
}

.header__brand {
  flex-shrink: 0;
}

.brand__link {
  display: flex;
  align-items: baseline;
  gap: var(--spacing-xs);
  color: var(--color-text-white);
}

.brand__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: var(--color-accent-gold);
  color: var(--color-primary-bg);
  font-family: var(--font-headings);
  font-weight: 800;
  font-size: 1.25rem;
  border-radius: 4px;
  flex-shrink: 0;
}

.brand__text {
  font-family: var(--font-headings);
  font-weight: 800;
  font-size: 1.375rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  line-height: 1.2;
}

.brand__desc {
  display: none;
  font-family: var(--font-body);
  font-weight: 400;
  font-size: 0.75rem;
  color: var(--color-text-light);
  letter-spacing: 0.08em;
  margin-left: var(--spacing-sm);
  padding-left: var(--spacing-sm);
  border-left: 1px solid var(--color-border-line);
  line-height: 1.3;
}

.header__nav {
  display: none;
  position: absolute;
  top: var(--header-height);
  left: 0;
  right: 0;
  background: var(--color-primary-bg);
  border-top: 1px solid var(--color-border-line);
  padding: var(--spacing-md) var(--spacing-lg);
}

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

.nav__list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.nav__link {
  display: block;
  padding: var(--spacing-sm) 0;
  font-family: var(--font-headings);
  font-weight: 700;
  font-size: 0.875rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text-light);
  border-bottom: 1px solid transparent;
  transition: color var(--transition-base), border-color var(--transition-base);
}

.nav__link:hover,
.nav__link:focus-visible {
  color: var(--color-accent-gold);
  border-bottom-color: var(--color-accent-gold);
}

.nav__link[aria-current="page"] {
  color: var(--color-accent-red);
  border-bottom-color: var(--color-accent-red);
}

.nav__toggle {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: var(--spacing-sm);
  background: transparent;
  border: 1px solid var(--color-border-line);
  border-radius: 4px;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
}

.toggle__bar {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text-white);
  border-radius: 1px;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

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

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

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

.header__speedline {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(135deg, var(--color-accent-red), var(--color-accent-gold), transparent 70%);
  opacity: 0.7;
  z-index: 1;
}

@media (min-width: 768px) {
  .brand__desc {
    display: inline-block;
  }

  .header__nav {
    display: flex;
    position: static;
    border-top: none;
    padding: 0;
    background: transparent;
  }

  .nav__list {
    flex-direction: row;
    gap: var(--spacing-lg);
  }

  .nav__link {
    padding: 0;
    border-bottom: none;
    position: relative;
  }

  .nav__link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    right: 0;
    height: 2px;
    background: transparent;
    transition: background var(--transition-base);
  }

  .nav__link:hover::after,
  .nav__link:focus-visible::after {
    background: var(--color-accent-gold);
  }

  .nav__link[aria-current="page"]::after {
    background: var(--color-accent-red);
  }

  .nav__toggle {
    display: none;
  }
}

@media (min-width: 1024px) {
  .header__inner {
    padding: 0 var(--spacing-xl);
  }

  .nav__list {
    gap: var(--spacing-xl);
  }
}

.site-footer {
  background: var(--color-secondary-bg);
  border-top: 2px solid var(--color-border-line);
  position: relative;
  overflow: hidden;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--color-accent-red), var(--color-accent-gold), var(--color-accent-red));
  opacity: 0.5;
}

.footer__inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: var(--spacing-xl) var(--spacing-lg);
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-lg);
  position: relative;
  z-index: 1;
}

.footer__brand {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.footer__logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.footer__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  background: var(--color-accent-gold);
  color: var(--color-primary-bg);
  font-family: var(--font-headings);
  font-weight: 800;
  font-size: 1rem;
  border-radius: 3px;
}

.footer__name {
  font-family: var(--font-headings);
  font-weight: 800;
  font-size: 1.125rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--color-text-white);
}

.footer__tagline {
  font-family: var(--font-body);
  font-size: 0.8125rem;
  color: var(--color-text-light);
  letter-spacing: 0.05em;
}

.footer__trust {
  font-family: var(--font-body);
  font-size: 0.75rem;
  color: var(--color-text-light);
  line-height: 1.6;
  padding: var(--spacing-sm) var(--spacing-md);
  background: rgba(255,255,255,0.04);
  border-left: 3px solid var(--color-accent-gold);
  border-radius: 0 4px 4px 0;
  margin-top: var(--spacing-xs);
}

.footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-md);
  padding: var(--spacing-md) 0;
  border-top: 1px solid var(--color-border-line);
  border-bottom: 1px solid var(--color-border-line);
}

.footer__link {
  font-family: var(--font-headings);
  font-weight: 600;
  font-size: 0.8125rem;
  letter-spacing: 0.05em;
  color: var(--color-text-light);
  padding: var(--spacing-xs) 0;
  transition: color var(--transition-base);
}

.footer__link:hover,
.footer__link:focus-visible {
  color: var(--color-accent-gold);
}

.footer__contact {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.contact__item {
  font-family: var(--font-body);
  font-size: 0.8125rem;
  color: var(--color-text-light);
  letter-spacing: 0.02em;
}

.footer__meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--spacing-sm);
  padding-top: var(--spacing-sm);
  font-family: var(--font-body);
  font-size: 0.75rem;
  color: var(--color-text-light);
  opacity: 0.8;
}

.footer__icp {
  letter-spacing: 0.03em;
}

.footer__year {
  letter-spacing: 0.03em;
}

@media (min-width: 768px) {
  .footer__inner {
    grid-template-columns: 2fr 1fr 1fr;
    gap: var(--spacing-xl);
  }

  .footer__brand {
    grid-column: 1;
  }

  .footer__links {
    grid-column: 2;
    border-top: none;
    border-bottom: none;
    flex-direction: column;
    padding: 0;
    gap: var(--spacing-sm);
  }

  .footer__contact {
    grid-column: 3;
  }

  .footer__meta {
    grid-column: 1 / -1;
    border-top: 1px solid var(--color-border-line);
    padding-top: var(--spacing-md);
    margin-top: var(--spacing-sm);
  }
}

@media (min-width: 1024px) {
  .footer__inner {
    padding: var(--spacing-xl) var(--spacing-xl);
  }
}

.section-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
}

.section__title {
  font-family: var(--font-headings);
  font-weight: 800;
  font-size: clamp(1.5rem, 4vw, 2.5rem);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-white);
}

.section__sub {
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--color-text-light);
  margin-top: var(--spacing-sm);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-lg);
  font-family: var(--font-headings);
  font-weight: 700;
  font-size: 0.875rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border-radius: 4px;
  transition: background var(--transition-base), color var(--transition-base), border-color var(--transition-base), transform var(--transition-base);
  cursor: pointer;
  min-height: 44px;
}

.btn:hover,
.btn:focus-visible {
  transform: translateY(-1px);
}

.btn[data-variant="primary"] {
  background: var(--color-accent-red);
  color: var(--color-text-white);
  border: 2px solid var(--color-accent-red);
}

.btn[data-variant="primary"]:hover,
.btn[data-variant="primary"]:focus-visible {
  background: transparent;
  color: var(--color-accent-red);
}

.btn[data-variant="outline"] {
  background: transparent;
  color: var(--color-text-white);
  border: 2px solid var(--color-border-line);
}

.btn[data-variant="outline"]:hover,
.btn[data-variant="outline"]:focus-visible {
  border-color: var(--color-accent-gold);
  color: var(--color-accent-gold);
}

.btn[data-variant="ghost"] {
  background: transparent;
  color: var(--color-text-light);
  border: 2px solid transparent;
}

.btn[data-variant="ghost"]:hover,
.btn[data-variant="ghost"]:focus-visible {
  color: var(--color-text-white);
  background: rgba(255,255,255,0.05);
}

.tag-label {
  display: inline-flex;
  align-items: center;
  padding: var(--spacing-xs) var(--spacing-md);
  font-family: var(--font-headings);
  font-weight: 600;
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  border: 1px solid var(--color-border-line);
  border-radius: 20px;
  background: transparent;
  color: var(--color-text-light);
  cursor: pointer;
  transition: all var(--transition-base);
  min-height: 32px;
}

.tag-label:hover,
.tag-label:focus-visible {
  border-color: var(--color-accent-gold);
  color: var(--color-accent-gold);
}

.tag-label[data-active] {
  background: var(--color-accent-red);
  border-color: var(--color-accent-red);
  color: var(--color-text-white);
}

.card {
  background: var(--color-secondary-bg);
  border: 1px solid var(--color-border-line);
  border-radius: 6px;
  padding: var(--spacing-lg);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--color-accent-red), var(--color-accent-gold));
  opacity: 0;
  transition: opacity var(--transition-base);
}

.card:hover,
.card:focus-within {
  transform: translateY(-4px);
  box-shadow: 0 8px 32px rgba(0,0,0,0.3);
}

.card:hover::before,
.card:focus-within::before {
  opacity: 1;
}

.card__title {
  font-family: var(--font-headings);
  font-weight: 700;
  font-size: 1.125rem;
  letter-spacing: 0.05em;
  color: var(--color-text-white);
  margin-bottom: var(--spacing-sm);
}

.card__meta {
  font-family: var(--font-body);
  font-size: 0.8125rem;
  color: var(--color-text-light);
  line-height: 1.5;
}

.card__content {
  font-family: var(--font-body);
  font-size: 0.9375rem;
  color: var(--color-text-white);
  line-height: 1.6;
}

.data-number {
  font-family: var(--font-data);
  font-weight: 600;
  font-size: clamp(1.5rem, 5vw, 3rem);
  color: var(--color-data-font);
  letter-spacing: 0.02em;
  line-height: 1.1;
}

.speed-line {
  display: block;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--color-accent-red), var(--color-accent-gold), transparent);
  opacity: 0.4;
  width: 100%;
}

.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  z-index: 999;
  background: transparent;
  pointer-events: none;
}

.progress-bar__fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-accent-red), var(--color-accent-gold));
  width: 0%;
  transition: width 0.1s linear;
}

.back-to-top {
  position: fixed;
  bottom: var(--spacing-lg);
  right: var(--spacing-lg);
  z-index: 800;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--color-accent-red);
  color: var(--color-text-white);
  border: 2px solid var(--color-accent-red);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  cursor: pointer;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--transition-base), transform var(--transition-base), background var(--transition-base);
  pointer-events: none;
}

.back-to-top[data-visible] {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

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

.back-to-top::after {
  content: '↑';
  font-weight: 700;
  font-size: 1.25rem;
}

@media (prefers-reduced-motion: reduce) {
  .card {
    transition: none;
  }
  .card:hover {
    transform: none;
  }
  .back-to-top {
    transition: opacity 0.01ms;
  }
}

.grid {
  display: grid;
  gap: var(--spacing-lg);
  grid-template-columns: 1fr;
}

@media (min-width: 600px) {
  .grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 960px) {
  .grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

@media (min-width: 1024px) {
  .container {
    padding: 0 var(--spacing-xl);
  }
}

.content-area {
  padding: var(--spacing-xl) 0;
}

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

[hidden] {
  display: none !important;
}