SOURCE

const baiduCrs = new L.Proj.CRS(
  "EPSG:900913",
  "+proj=merc +a=6378206 +b=6356584.314245179 +lat_ts=0.0 +lon_0=0.0 +x_0=0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext  +no_defs",
  {
    resolutions: (function() {
      level = 19;
      var res = [];
      res[0] = Math.pow(2, 18);
      for (var i = 1; i < level; i++) {
        res[i] = Math.pow(2, 18 - i);
      }
      return res;
    })(),
    origin: [0, 0],
    bounds: L.bounds([20037508.342789244, 0], [0, 20037508.342789244])
  }
);

let map = L.map('map-container', {
    zoomControl: false,
    attributionControl: false,
  	crs: baiduCrs
});

map.setView([30.67, 104.07], 12);

// const url_temp = 'http://192.168.0.87:18131/appmaptile?lang=zh_cn&size=1&scale=1&style=8&x={x}&y={y}&z={z}';
const url_temp = 'http://192.168.0.173:8888/appmaptile?lang=zh_cn&size=1&scale=1&style=8&x={x}&y={y}&z={z}';
L.tileLayer( url_temp).addTo(map);

<div id="map-container"></div>

html, body {
  width: 100%;
  height: 100%;
}
#map-container {
  width: 100%;
  height: 100%;
}