JSFiddle - React, Tailwind, and code Playground

HTML

<div id="split">
<form>
    <fieldset>
        <legend><h1>Big Headline</h1>
            <h2>Small Headline</h2></legend>
<ul>
    <li class="fl">
        <label for="firstname">Label 1</label>
        <input type="text" id="label1" name="label1" tabindex="10" autocomplete="off">
    </li>

    <li class="fl">
        <label for="lastname">Label 2</label>
        <input type="text" id="label2" name="label2" tabindex="20" autocomplete="off">
    </li>

    <li class="fll">
        <label for="label3">Label 3</label>
        <input type="text" id="label3" name="label3" tabindex="10" autocomplete="off">
    </li>

    <li class="fll">
        <label for="label4">Label 4</label>
        <input type="text" id="label4" name="label4" tabindex="40" autocomplete="off">
</li>

    <li class="fd">
        <input type="checkbox" id="tandc" name="tandc" tabindex="30" autocomplete="off" />
        <label class ="tandc">this line should be on one line with that checkbox.</label>
    </li>


</ul>
    </fieldset>
</form>
</div>

CSS

#split {
    height: 286px;
    width: 440px;
}
 #split h1 {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 16px;
    font-weight: bold;
    text-decoration: none;
}
 #split h2 {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 13px;
    font-weight:lighter;
    text-decoration: none;
}
#split fieldset { 
    height: 230px;
    width: 440px;
    border: none;
}
#split legend { 
    font-family: Arial, Helvetica, sans-serif;
    font-size: 12px;
    font-weight: bold;
    text-decoration: none;
}
 #split ul {
    text-decoration: none;
    list-style-type: none;
}
label {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 12px;
    font-weight: bolder;
    text-decoration: none;
    width: 80px;
    display: block;
    margin-left: 2px;
    margin-bottom: 2px;
}
.tandc {
font-family: Arial, Helvetica, sans-serif;
font-size: 10px;
font-weight: bolder;
text-decoration: none;
width: 380px;
height: 15px;
display:inline-block;
}
#split input[type="checkbox"]{
      width: 10px;
}
#split input {
    color:#444444;
    font-size: 10px;
    padding-left:5px;
    margin-right: 20px;
    width: 160px;
    height: 18px;
}
.fl { 
    float: left; 
    margin-top: 30px;
}
.fll { 
    float: left; 
    margin-top:20px;
}
 #split form fieldset ul .fd {
    background-color:#3F9;
    width: 400px;
    height: 20px;
    margin-top: 10px;
    float:left;
}
 #split form fieldset ul .fd .tandc {
    background-color: #F63;
    width: 350px;
    margin-left: -5px;
    margin-bottom: 5px;
}