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                <html lang=“ja”>
    <meta charset=“UFT-8”>
    <title>border-bottom 使い方</title>
    <link rel="stylesheet" href="style.css">
    <p><spna class="border-bottom1">2pxの一重下線(赤)</span></p>
    <p><spna class="border-bottom2">4pxの二重下線(青)</span></p>
    <p><spna class="border-bottom3">6pxの点線下線(緑)</span></p>
    <p><spna class="border-bottom4">8pxの破線下線(橙)</span></p>


                /* 一重線の下線 */
.border-bottom1 {
    border-bottom:solid 2px red
/* 二重線の下線 */
.border-bottom2 {
    border-bottom:double 4px blue
/* 点線の下線 */
.border-bottom3 {
    border-bottom:dotted 6px green
/* 破線の下線 */
.border-bottom4 {
    border-bottom:dashed 8px orange