Hi, To make your height constant then give same value for both min-height and max-height properties.
For Example :
p
{
min-height:100px;
max-height:100px;
}
And to make your height to change based on precentage, then go with the following example
Example :
body {
margin: 0 auto;
height: 100%;
width: 100%;
}
.header {
height: 50%;
width: 100%;
position:absolute;
border: 1px solid red;
box-sizing:border-box;
}
please click this
link[
^] for reference.