JSFiddle - React, Tailwind, and code Playground

HTML

<div class="halfWidth">
    <div class="input-wrapper">
        <input type="text" placeholder="Input text here"/>
    </div>
    <button type="submit">Search</button>
</div>

CSS

.halfWidth {
    width:50%;
}
.input-wrapper {
    margin-right:100px;
}
input {
    float: left;
    width: 100%;
    -ms-box-sizing: border-box; /* ie8 */
    -khtml-box-sizing: border-box; /* konqueror */
    -webkit-box-sizing: border-box; /* Safari/Chrome, other WebKit */
    -moz-box-sizing: border-box;    /* Firefox, other Gecko */
    box-sizing: border-box;         /* Opera/IE 8+ */
    box-sizing: border-box; /* css3 rec */
}