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

:root {
  --bg: #0a0a0a;
  --text-primary: #ffffff;
  --text-secondary: #888888;
  --text-muted: #666666;
  --border: rgba(255, 255, 255, 0.35);
  --border-hover: rgba(255, 255, 255, 0.6);
  --font-sans: "Inter", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100dvh;
  font-family: var(--font-sans);
  background-color: var(--bg);
  color: var(--text-primary);
  overflow-x: hidden;
}

.page {
  position: relative;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}

.header {
  position: relative;
  z-index: 10;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 28px 40px;
}

.header__brand {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.28em;
  color: var(--text-muted);
  text-transform: uppercase;
}

.lang-switcher {
  position: relative;
  z-index: 10;
}

.lang-switcher__btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--text-secondary);
  font-family: inherit;
  font-size: 0.8125rem;
  font-weight: 400;
  cursor: pointer;
  transition: border-color 0.2s ease, background-color 0.2s ease, color 0.2s ease;
}

.lang-switcher__btn:hover {
  border-color: var(--border-hover);
  background-color: rgba(255, 255, 255, 0.04);
  color: var(--text-primary);
}

.lang-switcher__btn:focus-visible {
  outline: 2px solid rgba(255, 255, 255, 0.5);
  outline-offset: 3px;
}

.lang-switcher__arrow {
  transition: transform 0.2s ease;
}

.lang-switcher__btn[aria-expanded="true"] .lang-switcher__arrow {
  transform: rotate(180deg);
}

.lang-switcher__menu {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  min-width: 140px;
  padding: 6px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background-color: rgba(10, 10, 10, 0.95);
  backdrop-filter: blur(12px);
  list-style: none;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition: opacity 0.2s ease, visibility 0.2s ease, transform 0.2s ease;
}

.lang-switcher__menu.open {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.lang-switcher__item {
  width: 100%;
  padding: 10px 12px;
  border: none;
  border-radius: 8px;
  background: transparent;
  color: var(--text-secondary);
  font-family: inherit;
  font-size: 0.8125rem;
  font-weight: 400;
  text-align: left;
  cursor: pointer;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.lang-switcher__item:hover {
  background-color: rgba(255, 255, 255, 0.06);
  color: var(--text-primary);
}

.lang-switcher__item:active {
  background-color: rgba(255, 255, 255, 0.1);
}

.main {
  position: relative;
  z-index: 1;
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 24px 80px;
}

.hero {
  width: 100%;
  max-width: 640px;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.hero__logo {
  display: block;
  width: min(280px, 72vw);
  height: auto;
  margin-bottom: 40px;
}

.hero__title {
  font-size: clamp(1.375rem, 3.2vw, 1.75rem);
  font-weight: 600;
  line-height: 1.45;
  letter-spacing: 0.01em;
  margin-bottom: 20px;
}

.hero__desc {
  font-size: clamp(0.875rem, 2vw, 0.9375rem);
  line-height: 1.75;
  color: var(--text-secondary);
  max-width: 480px;
  margin-bottom: 36px;
}

.hero__cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  min-width: 140px;
  padding: 11px 28px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--text-primary);
  font-family: inherit;
  font-size: 0.875rem;
  font-weight: 400;
  letter-spacing: 0.02em;
  text-decoration: none;
  cursor: pointer;
  transition: border-color 0.2s ease, background-color 0.2s ease;
}

.hero__cta:hover {
  border-color: var(--border-hover);
  background-color: rgba(255, 255, 255, 0.04);
}

.hero__cta:focus-visible {
  outline: 2px solid rgba(255, 255, 255, 0.5);
  outline-offset: 3px;
}

.footer {
  position: relative;
  z-index: 1;
  padding: 24px 40px 32px;
}

.footer__copy {
  font-size: 0.75rem;
  color: var(--text-muted);
  letter-spacing: 0.01em;
}

@media (max-width: 768px) {
  .header {
    padding: 20px 20px;
  }

  .header__brand {
    font-size: 0.6875rem;
    letter-spacing: 0.22em;
  }

  .main {
    padding: 24px 20px 60px;
  }

  .hero__logo {
    width: min(240px, 78vw);
    margin-bottom: 32px;
  }

  .hero__desc {
    margin-bottom: 32px;
  }

  .footer {
    padding: 20px;
  }
}

@media (max-width: 480px) {
  .hero__title {
    line-height: 1.5;
  }

  .hero__desc {
    line-height: 1.8;
  }
}

@media (min-width: 1200px) {
  .header {
    padding: 32px 56px;
  }

  .footer {
    padding: 28px 56px 40px;
  }
}