* {
  margin: 0;
  padding: 0;
}

body {
  background-color: #f1f2f3;
}

.container {
  box-sizing: border-box;
  width: 100%;
  max-width: 1560px;
  min-width: 1240px;
  margin: 25px auto;
  position: relative;
  color: #333;
}

.container * {
  box-sizing: border-box;
}

header {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  margin-bottom: 25px;
  width: 100%;
}

header h1 {
  font-size: 2.2rem;
  margin-bottom: 10px;
  position: relative;
  display: inline-block;
}

header p {
  opacity: 0.9;
  font-size: 1rem;
}

.tool-container {
  background: white;
  border-radius: 10px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
  padding: 20px;
  margin-bottom: 25px;
}

.box{
  display: flex;
  gap: 20px;
  margin-bottom: 20px;
}

.handle{
  display: flex;
  gap: 30px;
}

.input-area,
.output-area {
  flex: 1;
  display: flex;
  flex-direction: column;
}


.container label {
  width: 120px;
  font-weight: 600;
  font-size: 1.1rem;
  margin-right: 6px;
}

.container textarea {
  flex: 1;
  min-height: 260px;
  padding: 15px;
  border: 1px solid #ddd;
  border-radius: 5px;
  font-size: 1.05rem;
  resize: vertical;
}

.container textarea:focus {
  outline: none;
  border-color: #3498db;
  box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
}

.key-input {
  flex: 1;
  padding: 12px 15px;
  width: 420px;
  border: 1px solid #ddd;
  border-radius: 5px;
  font-size: 1rem;
}

.container select {
  padding: 10px 15px;
  width: 100px;
  border: 1px solid #ddd;
  border-radius: 5px;
  background: white;
  font-size: 1rem;
}

.button-group {
  display: flex;
  gap: 15px;
  justify-content: center;
}

.btn {
  padding: 12px 40px;
  font-size: 1.05rem;
  border: none;
  border-radius: 5px;
  cursor: pointer;
  transition: all 0.3s;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.btn-primary {
  background: #3498db;
  color: white;
}

.btn-primary:hover {
  background: #2980b9;
}

.btn-success {
  background: #2ecc71;
  color: white;
}

.btn-success:hover {
  background: #27ae60;
}

.btn-warning {
  background: #f39c12;
  color: white;
}

.btn-warning:hover {
  background: #d35400;
}

.btn-danger {
  background: #e74c3c;
  color: white;
}

.btn-danger:hover {
  background: #c0392b;
}

.section-title {
  font-size: 1.3rem;
  color: #2c3e50;
  margin-bottom: 15px;
}

.info-section {
  background: white;
  border-radius: 10px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
  padding: 20px;
  margin-bottom: 25px;
}

.info-content {
  margin-bottom: 20px;
}

.info-content p {
  margin-bottom: 15px;
}

.alphabet-table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 20px;
  font-size: 0.9rem;
}

.alphabet-table th,
.alphabet-table td {
  border: 1px solid #ddd;
  padding: 8px 10px;
  text-align: center;
}

.alphabet-table th {
  background-color: #f8f9fa;
  font-weight: 600;
}

.alphabet-table tr:nth-child(even) {
  background-color: #f9f9f9;
}

.alphabet-table tr:hover {
  background-color: #f1f8ff;
}

.notice {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(0, 0, 0, 0.85);
  color: white;
  padding: 15px 30px;
  border-radius: 30px;
  font-size: 1rem;
  z-index: 1000;
  opacity: 0;
  transition: opacity 0.3s;
  pointer-events: none;
}

.notice.show {
  opacity: 1;
}

footer {
  text-align: center;
  color: #7f8c8d;
  font-size: 0.95rem;
}