.overview-content .a{background-image:url(./img/01-banner_web.jpg);}
.overview-content .b{background-image:url(./img/b.jpg);}
.overview-content .c{background-image:url(./img/c.jpg);}
.overview-content .d{background-image:url(./img/d.jpg);}
.overview-content .f{background-image:url(./img/f.jpg);}
.overview-content .g{background-image:url(./img/g.jpg);}
.overview-content .i{background-image:url(./img/i.jpg);}
@media (max-width:736px){
  .overview-content .a{background-image:url(./m/01-banner_m.jpg);}
  .overview-content .b{background-image:url(./m/b.jpg);}
  .overview-content .c{background-image:url(./m/c.jpg);}
  .overview-content .d{background-image:url(./m/d.jpg);}
  .overview-content .f{background-image:url(./m/f.jpg);}
  .overview-content .g{background-image:url(./m/g.jpg);}
  .overview-content .i{background-image:url(./m/i.jpg);}
}