JSFiddle - React, Tailwind, and code Playground

HTML

<hr class="style-one">
<hr class="style-two">
<hr class="style-three">
<hr class="style-four">
<hr class="style-five">
<hr class="style-six">
<hr class="style-seven">
<hr class="style-eight">

CSS

hr {margin: 20px 0;}

/* Gradient color1 - color2 - color1 */
hr.style-one {    border: 0;
    height: 1px;
    background: #333;
    background-image: -webkit-linear-gradient(left, #ccc, #333, #ccc); 
    background-image:    -moz-linear-gradient(left, #ccc, #333, #ccc); 
    background-image:     -ms-linear-gradient(left, #ccc, #333, #ccc); 
    background-image:      -o-linear-gradient(left, #ccc, #333, #ccc); 
}
 
/* Gradient transparent - color - transparent */
  	
hr.style-two {
    border: 0;
    height: 1px;
    background-image: -webkit-linear-gradient(left, rgba(0,0,0,0), rgba(0,0,0,0.75), rgba(0,0,0,0)); 
    background-image:    -moz-linear-gradient(left, rgba(0,0,0,0), rgba(0,0,0,0.75), rgba(0,0,0,0)); 
    background-image:     -ms-linear-gradient(left, rgba(0,0,0,0), rgba(0,0,0,0.75), rgba(0,0,0,0)); 
    background-image:      -o-linear-gradient(left, rgba(0,0,0,0), rgba(0,0,0,0.75), rgba(0,0,0,0)); 
}
 
/* Double-color dashed line */
  	
hr.style-three {
    border: 0;
    border-bottom: 1px dashed #ccc;
    background: #999;
}
 
/* Single-direction drop shadow */
  	
hr.style-four {
    height: 12px;
    border: 0;
    box-shadow: inset 0 12px 12px -12px rgba(0,0,0,0.5);
}
 
/* Flaired edges, by Tomas Theunissen */
  	
hr.style-seven {
    height: 30px;
    border-style: solid;
    border-color: black;
    border-width: 1px 0 0 0;
    border-radius: 20px;
}
hr.style-seven:before { /* Not really supposed to work, but does */
    display: block;
    content: "";
    height: 30px;
    margin-top: -31px;    
    border-style: solid;
    border-color: black;
    border-width: 0 0 1px 0;
    border-radius: 20px;
}
 
/* Glyph, by Harry Roberts */
    	
hr.style-eight {
    padding: 0;
    border: none;
    border-top: medium double #333;
    color: #333;
    text-align: center;
}
hr.style-eight:after {
    content: "§";
    display: inline-block;
    position: relative; 
    top: -0.7em;  
    font-size: 1.5em;
    padding: 0 0.25em;
    background:...