gantt
    title 从三家分晋到三家归晋
    dateFormat  YYYY
    春秋:CQ,0001,295y
    战国:ZG,after CQ,254y
    秦:QIN,after ZG,19y
    西汉:XH,after QIN,211y
    耶稣纪年元年:crit,milestone,JS,0770,1y
    新:XIN,after XH,16y
    东汉:DH,after XIN,195y
    西晋:XJ,after CW,51y
    section 三国
    曹魏:CW,after DH,46y
    蜀汉:SH,after DH,42y
    孙吴:SW,after DH,51y