JSFiddle - React, Tailwind, and code Playground

HTML

<div class="main">
            <div class="panel">
                <a href="#login_form" id="login_pop" onmouseup="document.getElementById('login').select();">Log In</a>
               
            </div>

        </div>

        <!-- popup form #1 -->
        <a href="#x" class="overlay" id="login_form"></a>
        <div class="popup">
            <h2>Welcome Guest!</h2>
            <p>Please enter your login and password here</p>
            <div>
                <label for="login">Login</label>
                <input type="text" id="login" value="" autofocus />
            </div>
            <div>
                <label for="password">Password</label>
                <input type="password" id="password" value="" />
            </div>
            <input type="button" value="Log In" />

            <a class="close" href="#close"></a>
        </div>

CSS

.main {
    background: #f8f8f8 url(superhero.png) no-repeat;
    width: 469px;
    height: 450px;
    margin: 50px auto; 
	-moz-box-shadow: 0 3px 3px rgba(255,255,255,.1), 0 3px 0 #bbb, 0 4px 0 #aaa, 0 5px 5px #444;
    -webkit-box-shadow: 0 3px 3px rgba(255,255,255,.1), 0 3px 0 #bbb, 0 4px 0 #aaa, 0 5px 5px #444;
    box-shadow: 0 3px 3px rgba(255,255,255,.1), 0 3px 0 #bbb, 0 4px 0 #aaa, 0 5px 5px #444;
    -moz-border-radius: 10px;
    -webkit-border-radius: 10px;
    border-radius: 10px;
}
.panel {
    height: 34px;
    padding: 10px;
}
.panel a#login_pop, .panel a#join_pop {
    border: 2px solid #07839f;
    color: #fff; background-color: #0483a0;
	background-image: -webkit-gradient(linear, left top, left bottom, from(#31b2c3), to(#0483a0));
	background-image: -webkit-linear-gradient(top, #31b2c3, #0483a0);
	background-image: -moz-linear-gradient(top, #31b2c3, #0483a0);
	background-image: -ms-linear-gradient(top, #31b2c3, #0483a0);
	background-image: -o-linear-gradient(top, #31b2c3, #0483a0);
	background-image: linear-gradient(top, #31b2c3, #0483a0);
    display: block;
    float: right;
    margin-right: 10px;
    padding: 5px 10px;
    text-decoration: none;
    text-shadow: 1px 1px #000;

    -webkit-border-radius: 10px;
    -moz-border-radius: 10px;
    -ms-border-radius: 10px;
    -o-border-radius: 10px;
    border-radius: 10px;
}
a#login_pop:hover, a#join_pop:hover {
    border-color: #31b2c3; background:#31b2c3;
}
.overlay {
    background-color: rgba(0, 0, 0, 0.6);
    bottom: 0;
    cursor: default;
    left: 0;
    opacity: 0;
    position: fixed;
    right: 0;
    top: 0;
    visibility: hidden;
    z-index: 1;

    -webkit-transition: opacity .5s;
    -moz-transition: opacity .5s;
    -ms-transition: opacity .5s;
    -o-transition: opacity .5s;
    transition: opacity .5s;
}
.overlay:target {
    visibility: visible;
    opacity: 1;
}
.popup h2{color:#07839f; line-height:1.8em}
.popup {
    background-color: #fff;
    border: 3px solid #fff;
   ...