.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    opacity: 0;
    visibility: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: opacity 0.2s ease, visibility 0.2s ease;
}

.overlay.active {
    opacity: 1;
    visibility: visible;
}

.popup {
    background: #fff;
    padding: 20px;
    border-radius: 8px;
    width: 33%;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.25);
    position: relative;
}

.close-btn {
    position: absolute;
    top: 10px;
    right: 10px;
    font-size: 18px;
    cursor: pointer;
    background: none;
    border: none;
}

.popup h3 {
    margin: 0 0 20px;
    text-align: center;
}

.popup .form-group {
    margin-bottom: 15px;
}

.popup input[type="url"] {
    width: calc(100% - 80px);
    padding: 8px;
    border: 1px solid #ccc;
    border-radius: 4px;
}