:root{--primary-color: #3498db;--secondary-color: #2ecc71;--text-color: #333}body{font-family:Open Sans,sans-serif;color:var(--text-color);margin:0;padding:0}.text-primary{color:var(--primary-color)}.btn-primary{background-color:var(--primary-color);color:#fff;padding:10px 20px;border:none;border-radius:4px;cursor:pointer}.btn-primary:hover{background-color:#2980b9}.fade-in{animation:fadeIn .5s ease-in}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}button:disabled,button[disabled],.btn:disabled,.btn.disabled{cursor:not-allowed!important}