left side

center

right side

#main{ width: 90%; max-width: 795px; margin: auto; border: 2px solid blue; } #header{ border: 2px solid yellow; text-align: center; } #columns{ display: flex; } #leftcol{ width: 25%; float: left; border: 2px solid red; } #centercol{ border: 2px solid green; margin-left: auto; margin-right: auto; width: 50%; } #rightcol{ width: 25%; float: right; border: 2px solid red; } #footer{ border: 2px solid yellow; text-align: center; }