#app{font-family:Avenir,Helvetica,Arial,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;color:#2c3e50;width:96%;padding:0 2%;max-width:1380px;margin:10px auto}.mb-2{text-align:center}.category-container{margin-bottom:20px}.category-item{margin-bottom:15px}.first-level{font-weight:700;font-size:16px;color:#333;margin-bottom:8px}.second-level{padding-left:20px}.sub-category{color:#666;padding:4px 0;font-size:14px;cursor:pointer;position:relative;padding-left:15px}.sub-category:before{content:"•";position:absolute;left:0;color:#666}.sub-category:hover{color:#409eff}.content{padding:20px}.error,.loading{text-align:center;padding:20px}.error{color:#f56c6c}