html,
body {
  margin: 0;
  width: 100%;
  background-image: linear-gradient(
    to right top,
    #051937,
    #004d7a,
    #008793,
    #00bf72,
    #a8eb12
  );
}

* {
  box-sizing: border-box;
}
body {
  padding-top: 50px;
}

h1 {
  margin-top: 0;
  text-align: center;
  color: white;
  text-shadow: black 0.1em 0.1em 0.2em;
  color: white;
  font-size: 35px;
  font-family: "Franklin Gothic Medium";
}

#description {
  color: white;
  text-shadow: black 0.1em 0.1em 0.2em;
  font-size: 20px;
  text-align: center;
  font-style: italic;
  font-family: "Franklin Gothic Medium";
  margin-bottom: 0;
}
form {
  background: rgba(200, 30, 200, 0.3);
  padding: 21px;
  margin: 5px auto;
  border-radius: 1%;
  width: 80%;
  min-width: 350px;
  max-width: 600px;
}
label,
p {
  color: white;
  font-size: 18px;
}
#name,
#email,
#number,
#submit,
textarea {
  display: block;
  width: 100%;
}
img {
  width: 60%;
  min-width: 350px;
  max-width: 600px;
  height: auto;
  display: block;
  margin-left: auto;
  margin-right: auto;
  filter: drop-shadow(5px 5px 5px rgb(10, 70, 73));
}
#esfumado {
  width: 60%;
  min-width: 150px;
  max-width: 300px;
  height: auto;
  display: block;
  margin-left: auto;
  margin-right: auto;
  filter: drop-shadow(5px 5px 5px rgb(176, 204, 205));
}
#curso,
#serie {
  display: inline-block;
  width: 200px;
  margin-top: 8px;
  margin-bottom: 12px;
}
input {
  margin-bottom: 10px;
  margin-top: 5px;
  padding: 8px 5px;
  border-radius: 5px;
  border: none;
}
select {
  min-width: 200px;
  padding: 8px 5px;
  border-radius: 5px;
  border: none;
}
div > label {
  display: block;
}

.estrategia > label {
  display: inline;
  margin-right: 15px;
}
textarea {
  height: 80px;
  margin-bottom: 20px;
  border-radius: 10px;
}

/* CSS */
.button-85 {
  padding: 0.6em 2em;
  border: none;
  outline: none;
  color: rgb(255, 255, 255);
  background: #111;
  cursor: pointer;
  position: relative;
  z-index: 0;
  border-radius: 10px;
  user-select: none;
  -webkit-user-select: none;
  touch-action: manipulation;
}

.button-85:before {
  content: "";
  background: linear-gradient(
    45deg,
    #ff0000,
    #ff7300,
    #fffb00,
    #48ff00,
    #00ffd5,
    #002bff,
    #7a00ff,
    #ff00c8,
    #ff0000
  );
  position: absolute;
  top: -2px;
  left: -2px;
  background-size: 400%;
  z-index: -1;
  filter: blur(5px);
  -webkit-filter: blur(5px);
  width: calc(100% + 4px);
  height: calc(100% + 4px);
  animation: glowing-button-85 20s linear infinite;
  transition: opacity 0.3s ease-in-out;
  border-radius: 10px;
}

@keyframes glowing-button-85 {
  0% {
    background-position: 0 0;
  }
  50% {
    background-position: 400% 0;
  }
  100% {
    background-position: 0 0;
  }
}

.button-85:after {
  z-index: -1;
  content: "";
  position: absolute;
  width: 100%;
  height: 100%;
  background: #222;
  left: 0;
  top: 0;
  border-radius: 10px;
}