.flex-container1 {
  display: flex;
  justify-content: center;
  align-items: center;
  background-color: lightgreen;
  height: 350px;
}
.flex-container1 .box {
  width: 200px;
}

.flex-container2 { 
  display: flex;
  justify-content: space-around;
  background-color: yellow;
  height: 400px;
}
.flex-container2 .box {
  width: 100px;
  height: 150px;
  align-self: flex-end;
}
.flex-container2 .box1 {
  width: 100px;
  height: 150px;
  align-self: flex-start;
}

.flex-container3 {
  display: flex;
  background-color: lightgreen;
  justify-content: center;
  align-items: center;
  height: 500px;
}
.flex-container3 .box {
  width: 100px;
}

.blue{
  background-color: blue;
  width: 300px;
  text-align: center;
  border: 1px black solid;
}

.border {
  border: 1px black solid;
  width: 100%;
}

.flex-container4 {
  display: flex;
}
.flex-container4 .box {
  width: 100px;
  height: 150px;
}
.flex-container4 .box2 {
  width: 100px;
  height: 150px;
}