:root {
  --header-h: 60px;
  --footer-h: 52px;
}

body {
  padding-top: var(--header-h);
  padding-bottom: var(--footer-h);
  min-height: 100vh;
}

.app {
  max-width: 1100px;
  width: 100%;
  margin: 0 auto;
  padding: var(--sp-xl) var(--sp-lg) var(--sp-lg);
}

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 200;
  height: var(--header-h);
  background: var(--c-bg);
  border-bottom: 1px solid var(--c-border);
  display: flex;
  align-items: center;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.header__inner {
  max-width: 1100px;
  width: 100%;
  margin: 0 auto;
  padding: 0 var(--sp-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-md);
}

.header__brand {
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
  flex-shrink: 0;
}

.header__icon {
  display: block;
  flex-shrink: 0;
  width: 28px;
  height: 28px;
}

.header__title {
  font-size: var(--fs-xl);
  font-weight: 700;
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.header__subtitle {
  color: var(--c-text-muted);
  font-size: var(--fs-sm);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.tabs {
  display: flex;
  gap: var(--sp-xs);
  border-bottom: 1px solid var(--c-border);
  margin-bottom: var(--sp-xl);
}

.tab {
  background: none;
  border: none;
  color: var(--c-text-muted);
  padding: 0.75rem 1.25rem;
  font-size: var(--fs-base);
  font-weight: 500;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  transition: all 0.15s ease;
}

.tab:hover {
  color: var(--c-text);
}

.tab--active {
  color: var(--c-accent);
  border-bottom-color: var(--c-accent);
}

.panel {
  display: none;
}

.panel--active {
  display: block;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.25rem;
}

.content {
  min-height: 200px;
}

.footer {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 200;
  height: var(--footer-h);
  background: var(--c-bg);
  border-top: 1px solid var(--c-border);
  display: flex;
  align-items: center;
}

.footer__inner {
  max-width: 1100px;
  width: 100%;
  margin: 0 auto;
  padding: 0 var(--sp-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-md);
  font-size: var(--fs-xs);
  color: var(--c-text-muted);
}

.footer__links {
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
  flex-shrink: 0;
}

.footer__sep {
  opacity: 0.4;
}

@media (max-width: 768px) {
  :root {
    --header-h: 52px;
    --footer-h: 64px;
  }

  .app {
    padding: var(--sp-lg) var(--sp-md) var(--sp-md);
  }

  .header__subtitle {
    display: none;
  }

  .header__title {
    font-size: var(--fs-lg);
  }

  .theme-toggle {
    width: 1.75rem;
    height: 1.75rem;
  }

  .tabs {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }

  .tabs::-webkit-scrollbar {
    display: none;
  }

  .tab {
    padding: 0.6rem 1rem;
    font-size: var(--fs-sm);
    white-space: nowrap;
  }

  .grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .footer__inner {
    flex-direction: column;
    gap: 0.2rem;
    justify-content: center;
    padding: var(--sp-xs) var(--sp-md);
  }
}

@media (max-width: 480px) {
  .app {
    padding: var(--sp-md) var(--sp-sm) var(--sp-sm);
  }

  .header__title {
    font-size: var(--fs-base);
  }

  .footer__meta {
    display: none;
  }
}