body{background-color:#0f0f0f} h1,h2,h3,h4,h5,h6,p,li,ul,ol,td,th{color:#777777}
table{font-family:arial,sans-serif;border-collapse:collapse;width: 100%}/*
tr:nth-child(even){background-color: #aaaaaa;}*/
.a{width:500px;height:auto;margin-left:5px;margin-right:auto;/*margin-top:40px;padding-top:20px;*/}
.b{margin-left:12px}
.c{width:500px;height:auto;margin-left:auto;margin-right:5px}
article{width:300px;height:auto;padding-left:5px;padding-right:5px;border-collapse:collapse}
.tut-sqr{width:450px;max-height:900px;padding:10px;margin:5px;border:1px solid #777777;overflow-y:auto;overflow-x:hidden;word-wrap:normal;}
.cc{display:flex;flex-wrap:wrap;justify-content:center;}
.title{text-align:center;height:40px;font-size:30px;}

.up{display:flex;flex-wrap:wrap;/*justify-content:center;*/border:1px solid #777777;}