html, body, main, header, footer {
  padding: 0px;
  margin: 0px;
}

/* 计算器标题 */
#calc-title {
  text-align: center;
  font-size: 24px;
  color: #333;
  margin: 20px 0;
}

/* 计算器容器 */
#calculator {
  max-width: 480px;
  margin: 0 auto;
  padding: 20px;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
}

/* 输入区域 */
#input-section {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.input-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.input-group label {
  font-size: 14px;
  font-weight: 600;
  color: #555;
}

.input-group .hint {
  font-size: 12px;
  font-weight: 400;
  color: #999;
  margin-left: 8px;
}

.input-group input {
  width: 100%;
  height: 44px;
  padding: 0 12px;
  border: 1px solid #ddd;
  border-radius: 8px;
  font-size: 15px;
  color: #333;
  outline: none;
  transition: border-color 0.2s;
  box-sizing: border-box;
}

.input-group input:focus {
  border-color: #4a90d9;
  box-shadow: 0 0 0 3px rgba(74, 144, 217, 0.1);
}

/* 按钮区域 */
#button-group {
  display: flex;
  gap: 12px;
  margin-top: 4px;
}

.btn-primary {
  flex: 1;
  height: 44px;
  background: #4a90d9;
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
}

.btn-primary:hover {
  background: #357abd;
}

.btn-secondary {
  flex: 1;
  height: 44px;
  background: #f0f0f0;
  color: #666;
  border: none;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
}

.btn-secondary:hover {
  background: #e0e0e0;
}

/* 结果区域 */
#result-section {
  display: flex;
  gap: 16px;
  margin-top: 24px;
  padding: 20px;
  background: #f7f9fc;
  border-radius: 10px;
}

.result-item {
  flex: 1;
  text-align: center;
}

.result-label {
  display: block;
  font-size: 13px;
  color: #888;
  margin-bottom: 6px;
}

.result-value {
  display: block;
  font-size: 28px;
  font-weight: 700;
  color: #4a90d9;
  line-height: 1.2;
}

.result-unit {
  font-size: 14px;
  color: #999;
  margin-left: 2px;
}

/* fork 按钮区域 */
#__fork {
  text-align: center;
  margin: 24px 0;
}

#__fork button {
  padding: 10px 32px;
  background: #f5f5f5;
  color: #666;
  border: 1px solid #ddd;
  border-radius: 6px;
  font-size: 14px;
  cursor: pointer;
  transition: all 0.2s;
}

#__fork button:hover {
  background: #e8e8e8;
  color: #333;
}

/* 应用简介 */
#features {
  max-width: 680px;
  margin: 0 auto;
  padding: 24px 20px;
}

#features h2 {
  font-size: 20px;
  color: #333;
  margin-bottom: 12px;
}

#features p {
  font-size: 15px;
  color: #666;
  line-height: 1.8;
}

/* 应用场景 */
#scenarios {
  max-width: 680px;
  margin: 0 auto;
  padding: 0 20px 24px;
}

#scenarios h2 {
  font-size: 20px;
  color: #333;
  margin-bottom: 12px;
}

#scenarios ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

#scenarios li {
  font-size: 15px;
  color: #666;
  line-height: 1.8;
  padding: 6px 0;
  border-bottom: 1px solid #f0f0f0;
}

#scenarios li:last-child {
  border-bottom: none;
}

/* 常见问题 */
#FAQ {
  max-width: 680px;
  margin: 0 auto;
  padding: 0 20px 24px;
}

#FAQ h2 {
  font-size: 20px;
  color: #333;
  margin-bottom: 12px;
}

#FAQ dl {
  margin: 0;
}

#FAQ dt {
  font-size: 15px;
  font-weight: 600;
  color: #444;
  margin-top: 14px;
  margin-bottom: 4px;
}

#FAQ dd {
  font-size: 14px;
  color: #777;
  line-height: 1.8;
  margin: 0 0 8px 0;
}

/* footer */
footer {
  text-align: center;
  padding: 20px;
}

.page-info {
  font-size: 13px;
  color: #aaa;
}

.page-info a {
  color: #888;
  text-decoration: none;
}

.page-info a:hover {
  color: #555;
}

/* 响应式 */
@media (max-width: 520px) {
  #calculator {
    margin: 0 12px;
    padding: 16px;
    border-radius: 0;
    box-shadow: none;
  }

  #result-section {
    flex-direction: column;
    gap: 16px;
    padding: 16px;
  }

  .result-value {
    font-size: 24px;
  }

  #features,
  #scenarios,
  #FAQ {
    padding-left: 16px;
    padding-right: 16px;
  }
}