javascript multiple AND conditions in IF statement inside for loop javascript

I feel stupid because I´m stuck with a basic. I have three set of classes that contains paragraphs and I want to change the background color of each one depending on day (with New Dat.getDay().

I dont know how to mix for loop and if statements for each set of classes correctly. I guess it´s something simple but I missing it!

function changecolor() {
  var d = new Date();
  var n = d.getDay();
  var weekda = document.getElementsByClassName('weekdays');
  var sat = document.getElementsByClassName('saturday');
  var dom = document.getElementsByClassName('sun-fer');
  for (var i = 0; i < weekda.length && i < sat.length && i < dom.length; i++)
    if (n > 0 || n < 6) {
      weekda[i].setAttribute("style", "background-color:#0091ea;color:white;");
    }
  else if (n == 6) {
    sat[i].setAttribute("style", "background-color:#0091ea;color:white;");
  } else {
    dom[i].setAttribute("style", "background-color:#0091ea;color:white;");
  }
}
}
changecolor();