原文：

Flexbox is a one-dimensional layout model that simplifies the alignment and distribution of elements within a container. By setting display: flex on a parent element, its children become flex items that can be arranged horizontally or vertically. Properties like justify-content control the main axis alignment, while align-items handle the cross axis. Flexbox revolutionizes responsive design by replacing complex float-based layouts with intuitive, flexible arrangements that adapt naturally to different screen sizes.

翻译：

Flexbox是一种一维布局模型，简化了容器内元素的对齐和分布。通过在父元素上设置display: flex，其子元素变成flex项目，可以水平或垂直排列。justify-content等属性控制主轴对齐，而align-items处理交叉轴。Flexbox通过用直观、灵活的排列方式取代复杂的基于浮动的布局，彻底改变了响应式设计，使其自然地适应不同的屏幕尺寸。

词汇注释：

• one-dimensional /wʌn daɪˈmenʃənl/：一维的
• layout /ˈleɪaʊt/：布局
• alignment /əˈlaɪnmənt/：对齐
• distribution /ˌdɪstrɪˈbjuːʃn/：分布
• container /kənˈteɪnər/：容器
• axis /ˈæksɪs/：轴
• responsive /rɪˈspɑːnsɪv/：响应式的
• intuitive /ɪnˈtuːɪtɪv/：直观的