```css
body {
  font-family: "Segoe UI", Tahoma, sans-serif;
  background: linear-gradient(135deg, #e8f0ff, #f8faff);
  color: #243447;
  margin: 0;
  min-height: 100vh;
}

header {
  background: linear-gradient(120deg, #4a69bd, #6a89cc);
  color: #ffffff;
  text-align: center;
  padding: 35px 20px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

header h1 {
  margin: 0;
  font-size: 2rem;
  letter-spacing: 1px;
}

main {
  max-width: 700px;
  margin: 45px auto;
  padding: 0 25px;
}

fieldset {
  background-color: #ffffff;
  border: none;
  border-left: 5px solid #4a69bd;
  border-radius: 12px;
  padding: 28px;
  margin-bottom: 25px;
  box-shadow: 0 8px 20px rgba(74, 105, 189, 0.12);
}

legend {
  font-weight: 700;
  color: #4a69bd;
  padding: 0 12px;
  font-size: 1.1rem;
}

fieldset p {
  margin-bottom: 20px;
  line-height: 1.5;
}

input[type="text"],
input[type="email"] {
  display: block;
  width: 100%;
  box-sizing: border-box;
  padding: 13px 15px;
  margin-top: 8px;
  border: 2px solid #d9e2f3;
  border-radius: 8px;
  background-color: #f9fbff;
  color: #243447;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

select {
  display: block;
  margin-top: 8px;
  padding: 13px 15px;
  border: 2px solid #d9e2f3;
  border-radius: 8px;
  background-color: #f9fbff;
  color: #243447;
  cursor: pointer;
}

input[type="submit"] {
  background: linear-gradient(120deg, #4a69bd, #3867d6);
  color: #ffffff;
  font-weight: 700;
  font-size: 1rem;
  padding: 13px 26px;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  box-shadow: 0 5px 12px rgba(56, 103, 214, 0.25);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

input[type="submit"]:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 16px rgba(56, 103, 214, 0.3);
}

input[type="text"]:focus,
input[type="email"]:focus,
input[type="radio"]:focus,
input[type="submit"]:focus,
select:focus {
  outline: none;
  border-color: #4a69bd;
  box-shadow: 0 0 0 4px rgba(74, 105, 189, 0.2);
}

footer {
  text-align: center;
  font-weight: 600;
  color: #65748b;
  padding: 20px;
  margin-top: 20px;
}
```