:root{--primary-color: #667eea;--primary-hover: #5a6fd6;--primary-light: #e8ebff;--secondary-color: #764ba2;--background-color: #f5f7fa;--sidebar-color: #1a1f36;--text-color: #333;--text-muted: #6b7280;--border-color: #e5e7eb;--success-color: #10b981;--error-color: #ef4444;--warning-color: #f59e0b}*{box-sizing:border-box}html,body{margin:0;padding:0;height:100%;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,sans-serif;font-size:16px;line-height:1.5;color:var(--text-color);background:var(--background-color)}a{color:var(--primary-color);text-decoration:none}a:hover{text-decoration:underline}button,input,textarea,select{font-family:inherit}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-track{background:#f1f1f1}::-webkit-scrollbar-thumb{background:#c1c1c1;border-radius:4px}::-webkit-scrollbar-thumb:hover{background:#a1a1a1}.mention{background:var(--primary-light);color:var(--primary-color);padding:0 .25rem;border-radius:4px;font-weight:500}