% relative to parent width.
em relative to element font-size.
rem relative to root font-size.
vw & vh relative to viewport.
Example Code:
<div class="responsive">Responsive Box</div>

<style>
.responsive {
width:50%; height:10vh; font-size:2rem; background:#ffc107; text-align:center; line-height:10vh;
}
</style>
YouTube Description:
Jifunze kutumia responsive units kama %, em, rem, vw, vh kwa website zinazobadilika.
Hashtags:
#CSSUnits #ResponsiveDesign #Faulink