External CSS not linking for all elements

@font-face {
  font-family: h1font;
  src: url("static/Milky.ttf");
}

.center {
  margin: auto;
  width: 50%;
  border: 3px solid green;
  border-radius: 50px;
  padding: 9px;
  text-align: center;
}

body,
html {
  height: 100%;
  margin: 0;
}

.h1 {
  text-align: center;
  letter-spacing: 20px;
  color: white;
  font-size: 40px;
  font-family: h1font;
}

.bg {
  /* The image used */
  background-image: url("static/back.jpg");
  /* Full height */
  height: 100%;
  /* Center and scale the image nicely */
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
}

.wrapper {
  text-align: center;
}

.button_enter {
  cursor: pointer;
  display: inline-block;
  height: 40px;
  line-height: 40px;
  padding: 0 10px;
  color: white;
  border: 2px solid transparent;
  border-radius: 10px;
  border-right-color: #743ad5;
  border-left-color: #d53a9d;
  background: linear-gradient(to left, rgb(116, 58, 213) 0%, rgb(186, 58, 143) 70%, transparent 70%, transparent 85%, rgb(201, 58, 128) 85%, rgb(213, 58, 157) 100%) top/100% 2px, linear-gradient(to left, #743ad5 0%, #d53a9d 100%) bottom/100% 2px;
  background-repeat: no-repeat;
  position: absolute;
  top: 50%;
}

<div class="bg">
  <br>
  <h1 class="h1">John Doe</h1>
  <h1 class="h1">Photographer</h1>
  <br>
  <div class="wrapper">
    <a class="button_enter" style="padding:10px">Enter</a>
  </div>

</div>