/* Violet C语言教程 - 响应式：手机等小屏可用 */
@media (max-width: 768px) {
  html { font-size: 15px; }

  .site-header {
    padding: var(--space-sm) var(--space-md);
  }
  .site-title { font-size: 1.1rem; }

  .site-nav {
    padding: var(--space-sm) var(--space-md);
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-sm);
  }
  .nav-toggle {
    display: flex;
    transition: opacity 0.2s;
  }
  .nav-toggle .nav-toggle-bar {
    transition: transform 0.2s, opacity 0.2s;
  }
  .nav-list {
    display: none;
    flex-basis: 100%;
    flex-direction: column;
    gap: 0;
    padding: var(--space-sm) 0;
    border-top: 1px solid var(--color-border);
    margin-top: var(--space-xs);
  }
  .nav-list.is-open {
    display: flex;
  }
  .nav-list a {
    padding: var(--space-md);
    font-size: 0.95rem;
    border-radius: 4px;
    display: block;
  }

  .content {
    padding: var(--space-md) var(--space-sm);
    min-height: 50vh;
  }
  .content h1 { font-size: 1.5rem; }
  .content h2 { font-size: 1.15rem; }
  .content h3 { font-size: 1rem; }
  .content .lead { font-size: 1rem; }

  .content pre,
  .content pre code {
    font-size: 0.8rem;
    padding: 0.75em;
    border-radius: 4px;
  }
  .content pre { margin: var(--space-sm) 0; }

  .content .tip,
  .content .summary {
    padding: var(--space-sm) var(--space-md);
    margin: var(--space-md) 0;
  }
  .content .vocab-box {
    padding: var(--space-sm) var(--space-md);
  }
  .content .exam-question {
    padding: var(--space-md);
    margin-bottom: var(--space-lg);
  }

  .content .practice-area {
    margin: var(--space-lg) 0;
    padding: var(--space-md);
  }
  .content .practice-area .CodeMirror {
    min-height: 140px;
    font-size: 0.8rem;
  }
  .content .practice-run {
    padding: var(--space-md) var(--space-lg);
    min-height: 44px;
  }
  .content .practice-output {
    font-size: 0.8rem;
    padding: var(--space-sm);
  }

  .content .flowchart .flow-box {
    padding: 4px 8px;
    font-size: 0.85rem;
  }
  .content .flowchart .flow-row {
    gap: 12px;
    margin: 4px 0;
  }
  .content .flowchart .flow-branch { gap: 24px; }
  .content .flowchart.flowchart-seq {
    gap: 2px 0;
  }
  .content .flowchart .flow-diamond-wrap {
    width: 80px;
    height: 72px;
  }
  .content .flowchart .flow-diamond-wrap .flow-diamond-inner {
    width: 52px;
    height: 52px;
    margin-left: -26px;
    margin-top: -26px;
  }
  .content .flowchart .flow-diamond-wrap .flow-diamond-label {
    font-size: 0.75rem;
  }

  .site-footer {
    padding: var(--space-md);
    font-size: 0.85rem;
  }
  .content .chapter-nav {
    flex-direction: column;
  }
  .content .chapter-nav .chapter-next-link { margin-left: 0; }
}

@media (max-width: 480px) {
  html { font-size: 14px; }
  .nav-list a { font-size: 0.85rem; }
  .content { padding: var(--space-sm) var(--space-xs); }
  .content .practice-area .CodeMirror { min-height: 120px; }
}