   --card-bg: #1f2937;
        --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -1px rgba(0, 0, 0, 0.2);
      }

      * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
        font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
      }

      body {
        background-color: var(--bg-primary);
        color: var(--text-primary);
        min-height: 100vh;
        display: flex;
        flex-direction: colum