body {
     
}
header {
   background-color: #d1f2eb
}   
footer {
   background-color: #32e7e1

}

#main-content {
   display: flex;
}

#main-content--top{
   width: 100%;  
}

#main-content--left{
   width: 33%;
}
#main-content--center{
   width: 33%;
}

#main-content--right{
   width: 33%;  
}

#main-content--bottom{
   width: 100%;  
}