* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 20px;
  font-family: Arial, sans-serif;
  color: white;
  background: linear-gradient(135deg, #1e3c72, #2a5298);
}

.container {
  max-width: 900px;
  margin: auto;
  padding: 24px;
  border-radius: 22px;
  background: linear-gradient(145deg, #07152e, #0c1f44);
  box-shadow: 0 16px 35px rgba(0, 0, 0, 0.35);
}

h1 {
  text-align: center;
  margin-bottom: 28px;
  font-size: 2.4rem;
}

label {
  display: block;
  margin-top: 14px;
  margin-bottom: 8px;
  font-size: 1rem;
  font-weight: bold;
}

small {
  display: block;
  margin-top: 6px;
  color: #c7d6ff;
  line-height: 1.5;
}

input,
select,
textarea {
  width: 100%;
  padding: 12px;
  border: none;
  border-radius: 12px;
  background: #1c1c2b;
  color: white;
  font-size: 1rem;
  outline: none;
}

input::placeholder,
textarea::placeholder {
  color: #9fb3d9;
}

textarea {
  min-height: 140px;
  resize: vertical;
}

select {
  appearance: none;
  -webkit-appearance: none;
  -moz-appearance: none;
  background: #1c1c2b;
  color: white;
}

select option {
  background: #1c1c2b;
  color: white;
}

input:focus,
select:focus,
textarea:focus {
  box-shadow: 0 0 0 2px rgba(0, 198, 255, 0.45);
}

.row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 12px;
}

button {
  padding: 14px;
  border: none;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: bold;
  cursor: pointer;
  transition: 0.2s ease;
}

button:hover {
  transform: translateY(-1px);
}

.encrypt {
  background: linear-gradient(135deg, #00c6ff, #0072ff);
  color: #ffffff;
}

.decrypt {
  background: linear-gradient(135deg, #ff512f, #dd2476);
  color: #ffffff;
}

.info {
  margin-top: 16px;
  min-height: 24px;
  color: #ffef61;
  font-weight: bold;
}

.disabled {
  opacity: 0.55;
}

@media (max-width: 700px) {
  .row {
    grid-template-columns: 1fr;
  }
}