• Ignore !important to force override css to make an impact directly style of the element. For example:

document.getElementById("option_no_sequence").style.display = "block";
document.getElementById("option_sequence").style.display = "none";

• Apply !important on DOM element. For instance:

document.getElementById("option_no_sequence").setAttribute("style", "display: block !important;");
document.getElementById("option_sequence").setAttribute("style", "display: block !important;");