#rect-btn .submit-btn {
    position: relative;
}

#rect-btn .submit-btn.is-loading {
    pointer-events: none;
    opacity: 0.85;
}

#rect-btn .submit-btn .btn-spinner {
    display: none;
    width: 18px;
    height: 18px;
    margin-left: 10px;
    border: 2px solid rgba(255, 255, 255, 0.35);
    border-top-color: #fff;
    border-radius: 50%;
    animation: inquiry-btn-spin 0.8s linear infinite;
    vertical-align: middle;
}

#rect-btn .submit-btn.is-loading .btn-spinner {
    display: inline-block;
}

@keyframes inquiry-btn-spin {
    from {
        transform: rotate(0deg);
    }

    to {
        transform: rotate(360deg);
    }
}