function randomButtons () {
    var randomnumber1=Math.floor(Math.random()*5)+1;
    var randomnumber2=Math.floor(Math.random()*4)+1;
    var randomnumber3=Math.floor(Math.random()*4)+1;
    var randomnumber4=Math.floor(Math.random()*5)+1;
    document.getElementById("feature1").style.backgroundImage='url(/css/images/feature1-' + randomnumber1 + '.jpg)';
    document.getElementById("feature2").style.backgroundImage='url(/css/images/feature2-' + randomnumber2 + '.jpg)';
    document.getElementById("feature3").style.backgroundImage='url(/css/images/feature3-' + randomnumber3 + '.jpg)';
    document.getElementById("feature4").style.backgroundImage='url(/css/images/feature4-' + randomnumber4 + '.jpg)';
   //document.getElementById("feature1").style.backgroundImage='url(/css/images/feature1-1.jpg)';
   //document.getElementById("feature2").style.backgroundImage='url(/css/images/feature2-1.jpg)';
   //document.getElementById("feature3").style.backgroundImage='url(/css/images/feature3-1.jpg)';
   //document.getElementById("feature4").style.backgroundImage='url(/css/images/feature4-1.jpg)';
   
}