:root{--color-primary: #007bff;--color-secondary: #6c757d;--color-success: #28a745;--color-danger: #dc3545;--color-warning: #ffc107;--color-info: #17a2b8;--color-light: #f8f9fa;--color-dark: #343a40;--spacing-xs: 8px;--spacing-sm: 16px;--spacing-md: 24px;--spacing-lg: 32px;--spacing-xl: 48px;--font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;--font-size-sm: 14px;--font-size-base: 16px;--font-size-lg: 18px;--sidebar-width: 250px;--header-height: 60px}*{box-sizing:border-box}body{margin:0;min-width:320px;font-family:var(--font-family);font-size:var(--font-size-base);line-height:1.5;color:var(--color-dark);background-color:var(--color-light)}button,input,select{font:inherit}.btn{display:inline-block;padding:var(--spacing-sm) var(--spacing-md);border:1px solid transparent;border-radius:4px;text-decoration:none;cursor:pointer;transition:all .2s ease}.btn:disabled{cursor:not-allowed;opacity:.65}.btn-primary{background-color:var(--color-primary);color:#fff;border-color:var(--color-primary)}.btn-secondary{background-color:var(--color-secondary);color:#fff;border-color:var(--color-secondary)}.btn-danger{background-color:var(--color-danger);color:#fff;border-color:var(--color-danger)}.btn-sm{padding:8px 12px;font-size:var(--font-size-sm)}.form-group{margin-bottom:var(--spacing-md)}.form-label{display:block;margin-bottom:var(--spacing-xs);font-weight:500}.form-input{width:100%;padding:var(--spacing-sm);border:1px solid #ddd;border-radius:4px;font-size:var(--font-size-base)}.form-input:focus{outline:none;border-color:var(--color-primary);box-shadow:0 0 0 2px #007bff40}