.odd_number 
{
background-color:pink;
font-family:verdana,"DejaVu Sans",sans-serif;
}

#number_2
{
color:rgb(22, 84, 218);  
font-size:36px;  
}

.number_3
{
font-size:36px;
}

#number_4 
{
background:rgb(143, 228, 126);
font-size:24px;
font-weight:bold;    
}