svg+css 或者js制作打钩的动画效果CSS Transition通过改变Height实现展开收起元素从QQtabBar看css命名规范BEM的详细介绍css实现两栏布局，左侧固定宽，右侧自适应的

    
    



    
    完成

成功

h2 {
        font-family: Helvetica;
        font-size: 30px;
        margin-top: 20px;
        color: #333;
        opacity: 0;
    }
    input[type="checkbox"]:checked+ label ~ h2 {
        animation: .6s title ease-in-out;
        animation-delay: 1.2s;
        animation-fill-mode: forwards;
    }
    .circle {
        stroke-dasharray: 1194;
        stroke-dashoffset: 1194;
    }
    input[type="checkbox"]:checked + label + svg .circle {
        animation: circle 1s ease-in-out;
        animation-fill-mode: forwards;
    }
    .tick {
        stroke-dasharray: 350;
        stroke-dashoffset: 350;
    }
    input[type="checkbox"]:checked + label+ svg .tick {
        animation: tick .8s ease-out;
        animation-fill-mode: forwards;
        animation-delay: .95s;
    }
    @keyframes circle {
        from {
            stroke-dashoffset: 1194;
        }
        to {
            stroke-dashoffset: 2388;
        }
    }
    @keyframes tick {
        from {
            stroke-dashoffset: 350;
        }
        to {
            stroke-dashoffset: 0;
        }
    }
    @keyframes title {
        from {
            opacity: 0;
        }
        to {
            opacity: 1;
        }
    }
    label {
        display: inline-block;
        height: 38px;
        width: 38px;
        line-height: 38px;
        padding: 0 18px;
        background-color: #1E9FFF;
        color: #fff;
        white-space: nowrap;
        text-align: center;
        font-size: 14px;
        border: none;
        border-radius: 2px;
        cursor: pointer;
    }
    #d1 {
        display: flex;
        justify-content: center;
        min-height: 100px;
        flex-direction: column;
    }

  $("#btn1").on("click",function () {
       if($(this).text()==="完成"){
           $(".circle").css({'animation':'circle 1s ease-in-out','animation-fill-mode':'forwards'});
           $(".tick").css({'animation':'tick .8s ease-out','animation-fill-mode':'forwards','animation-delay':'.95s'});
           $("h2").css({'animation':'.6s title ease-in-out','animation-fill-mode':'forwards','animation-delay':'1.2s'})
           $(this).text("取消")
       }else{
           $(".circle").css({'animation':'none','animation-fill-mode':'none'});
           $(".tick").css({'animation':'none','animation-fill-mode':'none'});
           $("h2").css({'animation':'none','animation-fill-mode':'none'})
           $(this).text("完成")
       }
   });