form {
  max-width: 600px;
  margin: 60px auto 40px auto;
  /* ← ここで上下の間隔も調整 */
  background: #1e1e1e;
  padding: 2rem;
  border-radius: 10px;
  box-shadow: 0 0 12px rgba(0, 255, 136, 0.2);
}

label {
  display: block;
  margin-bottom: 1.5rem;
  font-size: 1rem;
  font-weight: bold;
}

input[type="text"],
input[type="email"],
textarea {
  width: 100%;
  padding: 0.8rem;
  background-color: #2c2c2c;
  color: #fff;
  border: 1px solid #444;
  border-radius: 6px;
  font-size: 1rem;
}

input:focus,
textarea:focus {
  border-color: #00ff88;
  outline: none;
}

button {
  background-color: #00ff88;
  color: #000;
  border: none;
  padding: 0.8rem 1.5rem;
  border-radius: 6px;
  font-size: 1rem;
  cursor: pointer;
}

button:hover {
  background-color: #00cc6a;
}

#result {
  margin-top: 1.5rem;
  font-weight: bold;
}

#result.success {
  color: #00ff88;
}

#result.error {
  color: #ff6b6b;
}

.required-mark {
  color: #ff5555;
  font-size: 0.9em;
  margin-left: 8px;
  font-weight: normal;
}

label input,
label textarea {
  display: block;
  margin-top: 0.8em;
  font-weight: normal;
}

.contact-contents-bottom {
  margin-top: 2rem;
  background-color: #1e1e1e;
  padding: 1rem;
  border-radius: 6px;
  max-height: 250px;
  overflow-y: auto;
  font-size: 0.85rem;
  color: #cccccc;
  line-height: 1.6;
  border: 1px solid #444;
}

.contact-contents-bottom span {
  display: block;
  font-weight: bold;
  color: #00ff88;
  margin-top: 1em;
}

.submit-area {
  margin-top: 1.5rem;
}