代码：

formatter:'{b}<br />\
                              <span style="display:inline-block;margin-right:5px;border-radius:10px;width:9px;height:9px;background-color:#5374E9"></span>\
                              {a0}：{c0}<br />\
                              <span style="display:inline-block;margin-right:5px;border-radius:10px;width:9px;height:9px;background-color:#FFA123"></span>\
                              {a1}：{c1}%<br />\
                              <span style="display:inline-block;margin-right:5px;border-radius:10px;width:9px;height:9px;background-color:#37C2CF"></span>\
                              {a2}：{c2}%<br />\
                              <span style="display:inline-block;margin-right:5px;border-radius:10px;width:9px;height:9px;background-color:#F97979"></span>\
                              {a3}：{c3}%<br />',