我這切換符怎么顯現成這樣！
<a class="left carousel-control" href="#ad-carousel" data-slide="prev"><span
? ? ? ? ? ? class="glyphicon glyphicon-chevron-left"></span></a>
? ? <a class="right carousel-control" href="#ad-carousel" data-slide="next"><span
? ? ? ? ? ? class="glyphicon glyphicon-chevron-right"></span></a>
2018-08-07
好了，查找了下，竟然是確實字體的緣故