.custom-underline {
    position: relative;
    text-decoration: none;
    color: #2c3e50;
}
.custom-underline::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -2px;
    width: 100%;
    height: 3px;
    background: linear-gradient(45deg, #3498db, #e74c3c);
    border-radius: 2px;
}