html,
body {
    height: 100%;
}

body {
    display: flex;
    align-items: center;
    padding-top: 40px;
    padding-bottom: 40px;
}

.form-signin {
   width: 100%;
max-width: 330px;
padding: 31px;
margin: auto;
border: 1px solid black;
border-radius: 5px;
}
.form-signin .checkbox {
    font-weight: 400;
}
.form-signin .form-control {
    position: relative;
    box-sizing: border-box;
    height: auto;
    padding: 10px;
    font-size: 16px;
}




html {
  height:100%;
}

body {
  margin:0;
}

.bg {
  animation:slide 3s ease-in-out infinite alternate;
  background-image: linear-gradient(-60deg, #6c3 50%, #09f 50%);
  bottom:0;
  left:-50%;
  opacity:.5;
  position:fixed;
  right:-50%;
  top:0;
  z-index:-1;
}

.bg2 {
  animation-direction:alternate-reverse;
  animation-duration:4s;
}

.bg3 {
  animation-duration:5s;
}

.content {
  background-color: rgba(0, 0, 0, 0.8);
  color: white;
  
}

h1 {
  font-family:monospace;
}

@keyframes slide {
  0% {
    transform:translateX(-25%);
  }
  100% {
    transform:translateX(25%);
  }
}