3-13.線を引こう
border-width: 1px;
border-width: thick;
border-width: 1px 4px 8px 4px;
border-style: solid
border-style: double
border-style: dashed
border-style: dotted
border-style: groove
border-style: ridge
border-style: inset
border-style: outset
border-style: dashed solid
線の色 boder-coror
border-color: tomato;
border-color: tomato;
border-color: tomato;
sitano senn
border-color: tomato;
border-color: tomato;