* {
  margin: 0;
  padding: 0;
}

body {
  background-color: #f1f2f3;
}

.container {
  box-sizing: border-box;
  width: 100%;
  max-width: 1640px;
  min-width: 1240px;
  margin: 25px auto;
  color: #333;
  display: flex;
  flex-direction: column;
}

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

/* 头部样式 */
header {
  position: relative;
  margin-bottom: 20px;
  text-align: center;
}

header h1 {
  font-size: 32px;
  margin-bottom: 5px;
}

header p {
  font-size: 16px;
  line-height: 1.6;
}

.tool-container {
  display: flex;
  gap: 20px;
  margin-bottom: 25px;
}

.input-section,
.output-section {
  flex: 1;
  background: white;
  border-radius: 12px;
  box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
  padding: 20px;
}

.section-title {
  font-size: 1.3rem;
  margin-bottom: 15px;
  color: #2c3e50;
  display: flex;
  align-items: center;
  gap: 10px;
}

textarea {
  width: 100%;
  height: 300px;
  padding: 15px;
  border: 1px solid #ddd;
  border-radius: 8px;
  font-size: 15px;
  line-height: 1.5;
  resize: none;
  margin-bottom: 20px;
  transition: border-color 0.3s;
}

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

.options-container {
  margin-bottom: 20px;
}

.option-group {
  margin-bottom: 20px;
}

.option-group:last-child {
  margin-bottom: 0;
}

.option-title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
  color: #34495e;
}

.options {
  display: flex;
  flex-wrap: wrap;
  gap: 15px;
}

.option {
  display: flex;
  align-items: center;
  gap: 8px;
}

input[type="radio"] {
  width: 18px;
  height: 18px;
  cursor: pointer;
}

.buttons {
  display: flex;
  gap: 15px;
  margin-top: 20px;
}

button {
  flex: 1;
  padding: 14px 20px;
  border: none;
  border-radius: 8px;
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

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

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

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

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

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

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

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

.output-box {
  background: #f8f9fa;
  border-radius: 8px;
  padding: 15px;
  min-height: 540px;
  font-size: 15px;
  line-height: 1.5;
  white-space: pre-wrap;
  overflow-wrap: break-word;
  border: 1px solid #ddd;
}

.features {
  background: white;
  border-radius: 12px;
  box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
  padding: 20px;
  margin-bottom: 25px;
}

.features-title {
  font-size: 1.8rem;
  text-align: center;
  margin-bottom: 20px;
  color: #2c3e50;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 25px;
}

.feature-card {
  background: #f8f9fa;
  border-radius: 10px;
  padding: 20px;
  transition: transform 0.3s;
}

.feature-icon {
  font-size: 2.5rem;
  margin-bottom: 15px;
}

.feature-title {
  font-size: 1.3rem;
  margin-bottom: 12px;
  color: #2c3e50;
}

.feature-desc {
  color: #7f8c8d;
  line-height: 1.6;
}

.notice {
  position: fixed;
  bottom: 30px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(0, 0, 0, 0.8);
  color: white;
  padding: 15px 30px;
  border-radius: 8px;
  font-size: 1.1rem;
  opacity: 0;
  transition: opacity 0.3s;
  pointer-events: none;
  z-index: 1000;
  max-width: 80%;
  text-align: center;
}

.notice.show {
  opacity: 1;
}

footer {
  text-align: center;
  color: #7f8c8d;
  font-size: 15px;
}