@media (max-width: 480px) {
  h1 {
    font-size: 22px;
  }

  input,
  button {
    font-size: 15px;
  }
}


body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  margin: 0;
  background-image: linear-gradient(
    to right,
    black,
    rgb(90, 90, 210),
    rgba(67, 199, 239, 0.637)
  );
}

main {
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 16px;
}


form {
  width: 100%;
  max-width: 420px;
  padding: 20px;
  background-color: white;
  border: 1px solid #ddd;
  border-radius: 12px;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

h1 {
  text-align: center;
  margin-bottom: 12px;
}

label {
  display: block;
  margin-top: 10px;
  margin-bottom: 4px;
  font-weight: bold;
}


input {
  width: 100%;
  padding: 10px;
  padding-left: 36px;
  box-sizing: border-box;
  border: 1px solid #aaa;
  border-radius: 4px;
  font-size: 14px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

input::placeholder {
  color: #999;
  font-size: 13px;
}

input:focus {
  outline: none;
  border-color: rgb(90, 90, 210);
  box-shadow: 0 0 0 2px rgba(90, 90, 210, 0.3);
}

input:focus::placeholder {
  color: transparent;
}

input:hover {
  border-color: #666;
}

input:hover:focus {
  border-color: rgb(90, 90, 210);
}

/* Estados de erro */
input:invalid:not(:placeholder-shown) {
  border-color: #d93025;
}

input:invalid:focus {
  box-shadow: 0 0 0 2px rgba(217, 48, 37, 0.3);
}


button {
  margin-top: 20px;
  width: 100%;
  padding: 10px;
  border: 1px solid black;
  border-radius: 4px;
  font-size: 14px;
  cursor: pointer;
  font-weight: bolder;
  color: white;
  background-image: linear-gradient(
    to bottom,
    rgba(67, 199, 239, 0.637),
    rgb(110, 110, 223)
  );
  transition: background-image 0.2s ease, transform 0.1s ease;
}

button:hover {
  background-image: linear-gradient(
    to bottom,
    rgba(67, 199, 239, 0.8),
    rgb(90, 90, 210)
  );
}

button:active {
  background-image: linear-gradient(
    to bottom,
    rgb(90, 90, 210),
    rgba(67, 199, 239, 0.8)
  );
  transform: scale(0.98);
}

button:focus {
  outline: 2px solid #000;
  outline-offset: 2px;
}


.link {
  text-align: center;
  margin-top: 12px;
}

a {
  color: rgb(90, 90, 210);
  text-decoration: none;
  display: block;
  padding: 4px 0;
  font-size: 14px;
}

a:hover {
  text-decoration: underline;
  font-weight: bolder;
}

a:focus {
  outline: 2px solid rgba(90, 90, 210, 0.4);
  outline-offset: 2px;
}


footer {
  color: white;
  font-weight: bolder;
  text-align: center;
  padding: 12px 0;
}