a {
  color: #efefef;
  text-decoration: none;
  margin-top:3px;
  font-size: 100%;
  line-height: 130%;
}
a:hover {
  color: #ffcc00;
}
.ninja_button0 {
  display: block;
  border: none;
  background-color: #4CAF50;
  padding: 0.1vw 0.2vw;
  font-size: 2vw;
  cursor: pointer;
  text-align: center;
  box-shadow:4px 6px 3px rgba(10%,10%,10%);
  transition: all 0.3s ease 0s;
  border-radius: 5px;
  outline: none;
}
.ninja_button0:hover {
  background-color: #59be5c;
}
.ninja_button1 {
  display: block;
  border: none;
  background-color: #4cafaf;
  padding: 0.1vw 0.2vw;
  font-size: 2vw;
  cursor: pointer;
  text-align: center;
  box-shadow:4px 6px 3px rgba(10%,10%,10%);
  transition: all 0.3s ease 0s;
  border-radius: 5px;
  outline: none;
}
.ninja_button1:hover {
  background-color: #5dbbbb;
}
.ninja_button2 {
  display: block;
  border: none;
  background-color: #aaaaaa;
  padding: 0;
  font-size: 2vw;
  cursor: pointer;
  text-align: center;
  box-shadow:none;
  outline: none;
}
.ninja_button2:hover {
  background-color: #999999;
}
.ninja_button3 {
  display: block;
  border: revert;
  background-color: #999999;
  padding: 0.1vw 0.2vw;
  font-size: 2vw;
  cursor: pointer;
  text-align: center;
  box-shadow:none;
  outline: none;
}
.ninja_button3:hover {
  transition-duration: 0.4s;
  background-color: #aaaaaa;
}