:root {
    --primary: #1890ff;
    --success: #52c41a;
    --warning: #faad14;
    --danger: #f5222d;
    --bg: #f5f7fa;
    --card-bg: #ffffff;
    --text: #333;
    --text-secondary: #666;
    --border: #e8e8e8;
    --sidebar-width: 220px;
    --topbar-height: 56px;
    --radius: 8px;
    --shadow: 0 2px 8px rgba(0,0,0,0.1);
}

* { margin:0; padding:0; box-sizing:border-box; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    font-size: 14px;
}
a { color: var(--primary); text-decoration: none; }
button { cursor: pointer; font-family: inherit; }
input, textarea, select { font-family: inherit; font-size: 14px; }