.button-ai { background-color: rgba(0, 0, 0, 0.5); color: #fff; border: none; padding: 10px 20px; text-align: center; text-decoration: none; display: inline-block; font-size: 16px; transition-duration: 0.4s; cursor: pointer; }
.button-ai:hover { background-color: rgba(0, 0, 0, 0.7); }
.button-ai:active { background-color: rgba(0, 0, 0, 0.9); }