*{
  margin: 0;
  padding: 0;
  font-family: sans-serif;
}
.banner{
  width: 100%;
  height: 100vh;
  background-image: linear-gradient(rgba(0,0,0,0.75),rgba(0,0,0,0.75)),url(images.jpg);
  background-size: cover;
  background-position: center;
}
.navbar {
    width: 85%;
    margin: auto;
    padding: 35px 0;
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.logo{
  width: 220px;
  cursor: pointer;
}
.navbar ul li{
  list-style: none;
  display: inline-block;
  margin: 0 20px;
  position: relative;
}
.navbar ul li a{
  text-decoration: none;
  color: #fff;
  text-transform: uppercase;
} 
.navbar ul li ::after{
  content: '';
  height: 3px;
  width: 0%;
  background: #009688;
  position: absolute;
  left: 0;
  bottom: -10px;
  transition: 0.5s;
}
.navbar ul li :hover::after{
  width: 100%;
}
.content{
  width: 100%;
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  text-align: center;
  color: white;
}
.content h1{
  font-size: 70px;
  margin-top: 80px;
}
.content p{
  margin: 20px auto;
  font-weight: 100;
  line-height: 25px;
}
button{
  width: 200px;
  padding: 15px 0;
  text-align: center;
  margin: 20px 10px;
  border-radius: 25px;
  font-weight: bold;
  border: 2px solid #009688;
  background: transparent;
  color: white;
  cursor: pointer;
  position: relative;
  overflow: hidden;
}
span{
  background: #009688;
  height: 100%;
  width: 0%;
  border-radius: 25px;
  position: absolute;
  left: 0;
  bottom: 0;
  z-index: -1;
  transition: 0.5s;
}
button:hover span{
  width:100%;
}
button:hover{
  border: none;
}