// ... existing code ...

html {
  font-size: calc(100vw / 375 * 16); // 假设设计稿宽度为375px，设置基础字体大小为16px

  @media screen and (max-width: 375px) {
    font-size: 16px; // 最小字体大小
  }

  @media screen and (min-width: 768px) {
    font-size: 24px; // 平板或大屏设备上的字体大小
  }
}

.ai-chat {
  height: 98vh;
  display: flex;
  flex-direction: column;
  background-color: #f5f5f5;

  .chat-header {
    background: linear-gradient(135deg, #a6ea66 0%, #ead1ff 100%);
    color: white;
    padding: 16px;
    text-align: center;
    font-size: 1.2rem; // 使用 rem 单位
    font-weight: bold;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  }

  .chat-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
  }

  .messages-container {
    flex: 1;
    padding: 16px;
    overflow-y: auto;
    scroll-behavior: smooth;

    &::-webkit-scrollbar {
      width: 4px;
    }

    &::-webkit-scrollbar-track {
      background: transparent;
    }

    &::-webkit-scrollbar-thumb {
      background: rgba(0, 0, 0, 0.2);
      border-radius: 2px;
    }
  }

  .message {
    margin-bottom: 16px;
    display: flex;
    align-items: flex-start;
    animation: fadeInUp 0.3s ease-out;

    &.user {
      flex-direction: row-reverse;

      .message-content {
        background: linear-gradient(135deg, #ff3535 0%, #FF0000 100%);
        color: white;
        margin-left: 0;
        margin-right: 12px;
      }
    }

    &.ai {
      flex-direction: row;

      .message-content {
        background: white;
        color: #333;
        margin-left: 12px;
        margin-right: 0;
        box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
      }
    }

    .avatar {
      width: 60px;
      height: 60px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 18px; // 可以保持不变或调整为 rem 单位
      flex-shrink: 0;

      &.user-avatar {
        background: linear-gradient(135deg, #df2626 0%, #d10a0a 100%);
        color: white;
      }

      &.ai-avatar {
        background: linear-gradient(135deg, #ff6b6b 0%, #feca57 100%);
        color: white;
      }
    }

    .message-content {
      max-width: 70%;
      padding: 12px 16px;
      border-radius: 18px;
      word-wrap: break-word;
      line-height: 1.5;
      font-size: 1rem; // 使用 rem 单位
      position: relative;

      .typing-indicator {
        display: flex;
        align-items: center;
        gap: 4px;

        .dot {
          width: 6px;
          height: 6px;
          border-radius: 50%;
          background-color: #999;
          animation: typing 1.4s infinite ease-in-out;

          &:nth-child(1) { animation-delay: -0.32s; }
          &:nth-child(2) { animation-delay: -0.16s; }
          &:nth-child(3) { animation-delay: 0s; }
        }
      }
    }
  }

  .input-container {
    background: white;
    padding: 16px;
    border-top: 1px solid #e0e0e0;
    display: flex;
    align-items: flex-end;
    gap: 12px;
    box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.1);

    .input-wrapper {
      flex: 1;
      position: relative;
    }

    .message-input {
      width: 100%;
      min-height: 90px;
      max-height: 120px;
      padding: 10px 16px;
      border: 1px solid #e0e0e0;
      border-radius: 20px;
      font-size: 1.2rem; // 使用 rem 单位
      line-height: 1.8;
      resize: none;
      outline: none;
      transition: all 0.3s ease;

      &:focus {
        border-color: #ffc6c6;
        background: white;
        box-shadow: 0 0 0 2px rgba(102, 126, 234, 0.1);
      }

      &::placeholder {
        color: #999;
      }
    }

    .send-button {
      width: 40px;
      height: 40px;
      border-radius: 50%;
      background: linear-gradient(135deg, #ff0000 0%, #af1403 100%);
      border: none;
      color: white;
      display: flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      transition: all 0.3s ease;
      flex-shrink: 0;

      &:hover {
        transform: scale(1.05);
        box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
      }

      &:active {
        transform: scale(0.95);
      }

      &:disabled {
        background: #ccc;
        cursor: not-allowed;
        transform: none;
        box-shadow: none;
      }
    }
  }

  .quick-questions {
    padding: 16px;
    background: white;
    border-top: 1px solid #e0e0e0;

    .quick-title {
      font-size: 1rem; // 使用 rem 单位
      color: #666;
      margin-bottom: 12px;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .questions-list {
      display: flex;
      flex-direction: column;
      gap: 8px;

      .question-item {
        padding: 12px 16px;
        background: #f9f9f9;
        border: 1px solid #e0e0e0;
        border-radius: 12px;
        font-size: 1rem; // 使用 rem 单位
        color: #333;
        cursor: pointer;
        transition: all 0.3s ease;
        text-align: left;

        &:hover {
          background: #667eea;
          color: white;
          border-color: #667eea;
          transform: translateY(-1px);
          box-shadow: 0 2px 8px rgba(102, 126, 234, 0.2);
        }

        &:active {
          transform: translateY(0);
        }
      }
    }
  }

  .empty-state {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 40px 20px;
    text-align: center;

    .empty-icon {
      font-size: 4rem; // 使用 rem 单位
      margin-bottom: 16px;
      opacity: 0.5;
    }

    .empty-title {
      font-size: 1.5rem; // 使用 rem 单位
      font-weight: bold;
      color: #333;
      margin-bottom: 8px;
    }

    .empty-desc {
      font-size: 1rem; // 使用 rem 单位
      color: #666;
      line-height: 1.5;
    }
  }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes typing {
  0%, 80%, 100% {
    transform: scale(0);
    opacity: 0.5;
  }
  40% {
    transform: scale(1);
    opacity: 1;
  }
}