示范课程设计：装上这扇门，家里颜值提升了，空间也好像变大了 body { fontfamily: Arial, sansserif; lineheight: 1.6; margin: 20px; padding: 0; } h1 { color: 333; textalign: center; } .lessoncontent { maxwidth: 800px; margin: 0 auto; } .section { marginbottom:...
