.header {
  margin-top: 5rem;
  text-align: center;
}

.github-corner svg {
  position: fixed;
}

.slideshow-container {
  display: flex;
  height: 560px;
}

.screenshots {
  display: flex;
  margin: 0 auto;
  flex-direction: column;
  position: relative;
  width: 700px;
}

.screenshots img {
  width: 700px;
  display: block;
  margin: auto auto 30px auto;
  border-radius: 6px;
  border: 2px solid #eee;
}

.slideshow img {
  position: absolute;
  top: 0;
  left: 0;
}

.title {
  text-align: center;
}

.row {
  margin-bottom: 2em;
}

.feature-bubble {
  max-width: 100%;
  margin-bottom: 1em;
}

.feature-bubble img {
  width: 100%;
  max-width: 250px;
}

.header-bubble-container {
  width: 100%;
  display: flex;
}

.header-bubble {
  display: flex;
  max-width: 250px;
  max-height: 250px;
  overflow: hidden;
  border-radius: 50%;
  position: relative;
  margin: 0 auto;
  border: 3px solid #CCC;
  box-sizing: border-box;
  margin-bottom: 2em;
}

.header-bubble .facebook-logo {
  position: absolute;
  margin: auto;
  width: 150px;
  height: 150px;
  top: 48.5px;
  left: 48.5px;
}

.footer-right {
  float: right;
}

.features .columns {
  text-align: center;
}

.download-buttons-bottom {
  text-align: center;
}

@media (max-width: 760px) {
  .screenshots, .screenshots img {
    width: 100%;
  }
  
  .slideshow-container {
    height: 450px;
  }
  
  .header-bubble {
    max-width: 100px;
    max-height: 100px;
  }
  
  .header-bubble .facebook-logo {
    position: absolute;
    margin: auto;
    width: 75px;
    height: 75px;
    top: 10px;
    left: 10px;
  }

}

@media (max-width: 550px) {
  .link-stack {
    display: block;
    float: none;
  }
  .columns {
    margin-bottom: 2em;
  }
  .slideshow-container {
    height: 350px;
  }
}