.align-right {
  text-align: right;
}

.alert {
  text-align: center;
  position: relative;
  background-color:lightgray;
  border-radius: 4px;
  padding: 1em;
  margin-bottom: 1em;
}

details {
  transition: 1.5s;
}

summary {
  background-color:#eee;
  border-radius: 0px;
  padding-left: 1em;
}

summary:hover {
  color: #fff;
  background-color:#aaa;
}

/*IEだけのぞく:IE11はdetail/summaryに未対応*/
_:-ms-lang(x)::-ms-backdrop, 
summary:hover {
  color: #000;
  background-color:#eee;
}

.note {
  font-size: 14px;
  padding-left: 2em;
}

.fileinfo {
  font-size: 12px;
  padding-right: 6px; 
}

.btn-dl {
  display: inline-block;
  width: 150px;
  text-align: center;
  background-color: #999;
  border: 2px solid #000;
  font-size: 16px;
  color: #000;
  text-decoration: none;
  font-weight: bold;
  padding: 0px 0px;
  border-radius: 0px; 
  margin-top: -8px;
  margin-bottom: 0;
  position: relative;
}

.btn-dl span {
  position: relative;
  z-index: 1;
}

.btn-dl::before,
.btn-dl::after {
  content: "";
  display: block;
  background-color: #FFF;
  width: 100%;
  height: 100%;
  position: absolute;
  top: 0;
  transition: .2s;
}

.btn-dl:hover:before,
.btn-dl:hover:after {
  top: 100%;
  height: 0;
  background-color: #FFF;
}

.btn-dl:hover {
  color: #FFF;
}