Стиль границы Mdn
pre {
height: 80px;
width: 120px;
margin: 20px;
padding: 20px;
display: inline-block;
background-color: palegreen;
border-width: 10px;
box-sizing: border-box;
}
/* border-style example classes */
.b1 {
border-style: none;
}
.b2 {
border-style: hidden;
}
.b3 {
border-style: dotted;
}
.b4 {
border-style: dashed;
}
.b5 {
border-style: solid;
}
.b6 {
border-style: double;
}
.b7 {
border-style: groove;
}
.b8 {
border-style: ridge;
}
.b9 {
border-style: inset;
}
.b10 {
border-style: outset;
}
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