#rectangle { width: 200px; height: 100px; backgrount-color: red; } #circle { width: 100px; height: 100px; -webkit-border-radius: 100px; -moz-border-radius: 100px; border-radius: 100px; background-color: red; }
#triangle-up { width: 0; height: 0; border-left: 50px solid transparent; border-right: 50px solid transparent; border-bottom: 100px solid red; }
#triangle-leftbottom { width: 0; height: 0; border-left: 100px solid red; border-top: 100px solid transparent; }
#triangle-righttop { width: 0; height: 0; border-right: 100px solid red; border-top: 100px solid transparent; }