CSS_html/css_WEB-ITnose で描いた絵

div{    width: 100px;    height: 100px;    background-color: red;}

div{    width: 100px;    height: 100px;    background-color: red;    border-radius: 50%;}

div{    width: 100px;    height: 50px;    background-color: red;    border-radius: 50%;}

div{    width: 0;    height: 0;    border: 50px solid transparent;    border-bottom-color: red;}

div{    width: 0;    height: 0;    border: 50px solid transparent;    border-width: 86.6px 50px;    border-bottom-color: red;}