.responsive-video {
    position: relative;
    padding-bottom: 56.25%;
    padding-top: 60px; overflow: hidden;
}

.responsive-video iframe,
.responsive-video object,
.responsive-video embed {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.size-video {
    max-width: 800px;
    margin: auto;
}

body {
  padding-top: 20px;
  padding-bottom: 20px;
}

.navbar {
  margin-bottom: 20px;
}

.jumbotron {
  text-align: center;
}

.center-block {
  display: block;
  margin-left: auto;
  margin-right: auto;
}

.vertical-align {
  display: flex;
  align-items: center;
}