コピペで使えるボーダー(下線)のカスタマイズサンプル一覧[HTML/CSS]

<p class="t8-border-1">Sample</p>

.t8-border-1{
    border-bottom: 3px solid #0dcaf0;
}

<p class="t8-border-1a">Sample</p>

.t8-border-1a{
    border-bottom: 3px solid #0dcaf0;
}

.t8-border-1a:after {
    position: absolute;
    padding: 0.5em;
    content: " ";
    display: block;
    border-bottom: solid 3px blue;
    bottom: -0.5px;
    left:-5px;
    width: 50%;
}

<p class="t8-border-1b"></p>

.t8-border-1b{
    border-bottom: 3px solid #0dcaf0;
}

<p class="t8-border-2">Sample</p>

.t8-border-2{
    border-bottom: 3px dashed #0dcaf0;
}

<p class="t8-border-3">Sample</p>

.t8-border-3{
    border-bottom: 3px dotted #0dcaf0;
}

<p class="t8-border-4">Sample</p>

.t8-border-4{
    border-bottom: 3px double #0dcaf0;
}

<p class="t8-border-5">Sample</p>

.t8-border-5{
   background: linear-gradient(transparent 70%, #0d6efd 70%);
}

<p class="t8-border-5a">Sample</p>

.t8-border-5a {
    position: relative;
    background-color: transparent;
    border-bottom: solid 2px #0d6efd;
    padding: 15px;
    min-width: 250px;
    max-width: 100%;
    text-align: center;
}
.t8-border-5a:before,
.t8-border-5a:after {
    content: "";
    position: absolute;
    top: 100%;
    left: 50%;
    -webkit-transform: translateX(-50%);
    transform: translateX(-50%);
}
.t8-border-5a:before {
    border: solid 12px transparent;
    border-top: solid 12px #0d6efd;
}
.t8-border-5a:after {
    border: solid 14px transparent;
    border-top: solid 14px #0d6efd;
    margin-top: -5px;
}
.t8-border-5a::after {
    border-color: transparent;
}

<p class="t8-border-6">Sample</p>

.t8-border-6 {
    position: relative;
    color: #fff;
    font-size:1.5em;
}

.t8-border-6:after {
    content: "";
    position: absolute;
    left: 0;
    bottom: 0;
    width: 100%;
    height: 10px;
    background: repeating-linear-gradient(-45deg, #0d6efd, #0d6efd 2px, transparent 2px, transparent 6px);
}

<p class="t8-border-7">Sample</p>

.t8-border-7 {
    color: #fff;
    font-size:1.5em;
    position: relative;
    padding: 0.5em 0;
}

<p class="t8-border-8">Sample</p>

.t8-border-8 {
    padding: 0.5rem 0 1rem;
    background: linear-gradient(90deg, #0dcaf0 0% 33%, #0dcaf0 33% 66%, #0dcaf0 66%);
    background-repeat: no-repeat;
    background-size: 3rem 0.3rem;
    background-position: bottom;
    font-weight: bold;
    font-size: 1.5em;
    text-align: center;
}

<p class="t8-border-9">Sample</p>

.t8-border-9{
    text-align: center;
}

.t8-border-9::after {
    position: absolute;
    left: 0;
    content: '';
    width: 100%;
    height: 2px;
    background: #0dcaf0;
    bottom: -1px;
    transform: scale(0, 1);
    transform-origin: center top;
    transition: transform 0.3s;  
}

.t8-border-9:hover::after {
    transform: scale(1, 1); 
}

<p class="t8-border-10">Sample</p>

.t8-border-10::after {
    position: absolute;
    left: 0;
    content: '';
    width: 100%;
    height: 2px;
    background: #0dcaf0;
    bottom: -1px;               
    transform: scale(0, 1);    
    transform-origin: left top; 
    transition: transform 0.5s; 
}

.t8-border-10:hover::after {
    transform: scale(1, 1);    
}

<p class="t8-border-10a">Sample</p>

.t8-border-10a::after {
    position: absolute;
    left: 0;
    content: '';
    width: 100%;
    height: 3px;
    background: #0dcaf0;
    bottom: -10px; 
    opacity: 0;
    visibility: hidden;
    transition: 0.5s;
}

.t8-border-10a:hover::after {
    visibility: visible;
    bottom: 5px;
    opacity: 1;
}

<p class="t8-border-12">Sample</p>

.t8-border-12 {
    padding: 0.5rem 0 1rem;
    background-image: url(http://temp8.plat4.net/wp-content/uploads/2023/09/Ciri_staroceanoverlayelectricfairyidolgirl4k_aad1e0c6-cf24-400c-9ac4-fd87a2350a99.png);
    background-repeat: repeat-x;
    background-size: 30rem 0.5rem;
    background-position: bottom;
    font-weight: bold;
    font-size: 1.5em;
    text-align: center;
}

<p class="t8-border-13">Sample</p>

.t8-border-13 {
    padding: 0.5rem 0 1rem;
    background-image: url(http://temp8.plat4.net/wp-content/uploads/2023/09/Ciri_staroceanoverlayelectricfairyidolgirl4k_aad1e0c6-cf24-400c-9ac4-fd87a2350a99.png);
    background-repeat: repeat-x;
    background-size: 30rem 0.5rem;
    font-weight: bold;
    font-size: 1.5em;
    text-align: center;
    animation: loop 20s linear infinite;
}

@keyframes loop {
    from {
        background-position: 0 0;
    }
    to {
        background-position: 2000px 0;
    }
}