buttons.html

<style>
  .Subscribe-button {
    background-color: rgb(204, 0, 0);
    transition: opacity 0.2s;
    border: none;
    height:36px;
    width:105px;
    border-radius: 2px;
    font-family: Arial;
    font-size: 18px;
    cursor: pointer;
    color: white;
    margin-right: 9px;
  }
  .Subscribe-button:hover{
    opacity: 0.7;
  }
  .Subscribe-button:active{
    opacity: 0.5;
  }
  .Join-button {
    border-width: 1px;
    transition: background-color 0.5s,
    color 0.5s;
    font-family: Arial;
    font-size: 15px;
    font-weight: 400;
    height: 36px;
    width: 50px;
    background-color:rgb(255, 255, 255);
    color: rgb(6,95, 212);
    border-radius:   2px;
    border-color: rgb(41, 118, 211);
    border-style: solid;
    cursor: pointer;
  }
  .Join-button:hover{
    background-color:rgb(41,118, 211);
    color:white;
  }
  .Join-button:active{
    opacity:0.7;
  }
  .Tweet-button {
    background-color: rgb(29, 155, 255);
    border-radius: 34px;
    margin-left: 9px;
    cursor: pointer;
    font-weight: bold;
    font-size: 15px;
    height: 36px;
    width: 74px;
    border:none;
    color: white;
    transition: box-shadow 0.2s;
  }
  .Tweet-button:hover{
    box-shadow: 5px 5px 10px rgba(0,0,0,0.1);

  }
</style>
<button class="Subscribe-button">
  Subscribe
</button>
<button class="Join-button">
  JOIN
</button>
<button class="Tweet-button">
  Tweet
</button>