header{
  background:#BBBBBB;
}
body{
  background:lightgray;
}
.caixa{
  position: relative;
  width: 940px;
  margin: 0 auto;
}

nav{
  position: absolute;
  top: 110px;
  right: 0;
}
nav li{
  display: inline;
  margin: 0 0 0 15px;
}

#sf3{
  width:60%;
}
form label, form legend{
  margin: 0 0 10px;
  display: block;
  font-size: 20px;
}
.input-padrao{
  display: block;
  margin: 0 0 20px;
  padding: 10px 25px;
  width: 50%;
}

.checkbox{
  margin: 20px 0;
}
.enviar{
  width:40%;
  padding:15px 0;
  background:orange;
  color:white;
  font-weight:bold;
  font-size:15px;
  border:none;
  border-radius:3px;
  transition:1s all;
  cursor:pointer;
}
.enviar:hover{
  background:darkorange;
  transform:scale(1.1);
}
footer{
  text-align: center;
  background: #000000;
  padding: 40px 0;
}

.copyright{
  color: #FFFFFF;
  font-size: 13px;
  margin: 20px 0 0;
}