*,*:before,*:after{-webkit-box-sizing:inherit;box-sizing:inherit}html{-webkit-box-sizing:border-box;box-sizing:border-box;font-size:62.5%}.btn,a.btn,button.btn{font-size:1.6rem;font-weight:700;line-height:1.5;position:relative;display:inline-block;padding:1rem 4rem;cursor:pointer;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none;user-select:none;-webkit-transition:all .3s;transition:all .3s;text-align:center;vertical-align:middle;text-decoration:none;letter-spacing:.1em;color:#212529;border-radius:.5rem}*,*:before,*:after{-webkit-box-sizing:inherit;box-sizing:inherit}html{-webkit-box-sizing:border-box;box-sizing:border-box;font-size:80.5%}body{padding:0}.btn,a.btn,button.btn{font-size:1.6rem;font-weight:700;line-height:1.5;position:relative;display:inline-block;padding:1rem 4rem;cursor:pointer;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none;user-select:none;-webkit-transition:all .3s;transition:all .3s;text-align:center;vertical-align:middle;text-decoration:none;letter-spacing:.1em;color:#212529;border-radius:.5rem}a.btn-border-shadow{padding:calc(1.5rem - 12px) 3rem 1.5rem;background:#fff}a.btn-border-shadow:before{position:absolute;top:-6px;left:-6px;width:100%;height:100%;content:"";-webkit-transition:all .3s ease;transition:all .3s ease;border:3px solid #000;border-radius:.5rem}a.btn-border-shadow:hover{padding:calc(1.5rem - 6px) 3rem}a.btn-border-shadow:hover:before{top:0;left:0}a.btn-border-shadow--color{border-radius:0;background:#ff0}a.btn-border-shadow--color:before{border-radius:0}span{　display:inline-block}