<div class="container">
  
  <form action="">
    <div class="embed-submit-field">
      <input type="text" placeholder="Write something"/>
      <button type="submit">Send</button>
    </div>
  </form>
</div>
//Begin template
body {
  background: #eee;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  box-sizing: border-box;
}

* {
  box-sizing: inherit;
}

.container {
  width: 400px;
  margin: 0 auto;
}

//End template

.embed-submit-field {
  position: relative;
  
  input {
    width: 100%;
    padding: 15px;
  }
  button {
    position: absolute;
    right: 10px;
    top: 7px;
    
    
    //Only styling from here, you can discard this
    -webkit-appearance: none;
    -moz-appearance: none;
    
    border: none;
    background: #ededed;
    border-radius: 3px;
    padding: 10px;
    
    transition: all .2s;
    
    &:hover {
      background-color: #37C88D;
      color: #fff;
      cursor: pointer;
    }
  }
}
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