Bài 3

*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
.box{
  height: 100px;
  background-color: coral;
  width: 30%;
  border: 1px solid black;
}
.box1{
  height: 30px;
  background-color: lightblue;
  margin: 5px 0;
}
.container{
  display: flex;
  justify-content: space-around;
  height: 500px;
  border: 1px solid black;
  align-items: center;
}
.khung{
  display: flex;
  justify-content: space-between;
  height: 300px;
  border: 1px solid black;
}
.hop1{
  display: flex;
  justify-content: space-between;
  flex-direction: column;
  align-items: end;
  width: 60%;
  background-color: lightgreen;
}
.hop2{
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  width: 35%;
  background-color: lightblue;
} 
.hop1, .hop2{
  height: 100%;
}
.hop2lon{
  border: 3px solid red;
  display: flex;
  justify-content: space-between;
}
.hopcon{
  height: 80px;
  width: 80px;
  background-color: coral;
}
nav{
  display: flex;
  justify-content: space-between;
  background-color: lightgreen;
  padding: 10px;
}
ul{
  list-style-type: none;
  display: flex;
}
li{
  margin: 0 10px;
}
a{
  text-decoration: none;
  color: black;
  transition: all 0.3s ;
}

a:hover{
  color:white;
  text-decoration: underline;
}