:root {
    --c-bg:              #f5f5f5;
    --c-surface:         #ffffff;
    --c-input:           #ffffff;
    --c-subtle:          #f0f0f0;
    --c-hover:           #f5f5f5;
    --c-hover2:          #f0f0f0;
    --c-course:          #e6f7ff;
    --c-text:            #333333;
    --c-muted:           #999999;
    --c-hint:            #888888;
    --c-border:          #dddddd;
    --c-grid:            #dddddd;
    --c-primary:         #1890ff;
    --c-accent:          #1890ff;
    --c-disabled-bg:     #fafafa;
    --c-disabled-text:   #bbbbbb;
    --c-border-input:    #d9d9d9;
    --c-border-soft:     #f0f0f0;
    --c-primary-dark:    #0d5aa7;
    --c-badge-user-bg:   #f0f5ff;
    --c-badge-user-text: #2f54eb;
    --c-badge-user-bdr:  #adc6ff;
}
@media (prefers-color-scheme: dark) {
    :root {
        --c-bg:              #1a1a1a;
        --c-surface:         #2d2d2d;
        --c-input:           #3a3a3a;
        --c-subtle:          #3a3a3a;
        --c-hover:           #444444;
        --c-hover2:          #4a4a4a;
        --c-course:          #1a3a4a;
        --c-text:            #e0e0e0;
        --c-muted:           #888888;
        --c-hint:            #aaaaaa;
        --c-border:          #444444;
        --c-grid:            #444444;
        --c-primary:         #0d5aa7;
        --c-accent:          #40a9ff;
        --c-disabled-bg:     #2a2a2a;
        --c-disabled-text:   #666666;
        --c-border-input:    #555555;
        --c-border-soft:     #3a3a3a;
        --c-primary-dark:    #0d5aa7;
        --c-badge-user-bg:   #1a1f3a;
        --c-badge-user-text: #85a5ff;
        --c-badge-user-bdr:  #2f54eb;
    }
}
* { box-sizing: border-box; }
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Arial, sans-serif;
    margin: 0;
    background: var(--c-bg);
    color: var(--c-text);
}