.content {
  min-height: 100vh;
  height: auto;
  transition: all 0.2s ease-in-out;
}

.button-collapse {
 position: fixed;
 left: 10px;
 top: 10px;
 z-index: 10;
}
header, section {
  padding: 20px;
}
.card {
  width: 100%;
  margin-bottom: 15px;
  color: #000;
}
@media(min-width: 1440px) {
  .content {
    padding-left: 250px;
  }
}
@media(max-width: 720px) {
  .main-header {
    font-size: 260%;
  }
}