.required-login {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    vertical-align: middle;
    margin-left: 6px;
    line-height: 1;
}

.wpmcp-custom-icon {
    display: inline-block;
    width: 20px;
    height: 20px;
    background: url('../images/chapter-permission-icon.png') no-repeat center center;
    background-size: contain;
    transition: transform 0.2s ease, filter 0.2s ease;
}

.required-login:hover .wpmcp-custom-icon,
.required-login:focus .wpmcp-custom-icon {
    transform: scale(1.06);
    filter: brightness(1.05);
}