/* 简单的Bootstrap备用样式 */
.container {
  width: 100%;
  padding-right: 15px;
  padding-left: 15px;
  margin-right: auto;
  margin-left: auto;
}
.row {
  display: flex;
  flex-wrap: wrap;
  margin-right: -15px;
  margin-left: -15px;
}
.col-6 {
  flex: 0 0 50%;
  max-width: 50%;
  padding: 0 15px;
}
.col-12 {
  flex: 0 0 100%;
  max-width: 100%;
  padding: 0 15px;
}
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  min-width: 0;
  word-wrap: break-word;
  background-color: #fff;
  background-clip: border-box;
  border: 1px solid rgba(0,0,0,.125);
  border-radius: 0.25rem;
}
.card-body {
  flex: 1 1 auto;
  padding: 1.25rem;
}
.btn {
  display: inline-block;
  font-weight: 400;
  text-align: center;
  vertical-align: middle;
  user-select: none;
  border: 1px solid transparent;
  padding: 0.375rem 0.75rem;
  font-size: 1rem;
  line-height: 1.5;
  border-radius: 0.25rem;
  transition: color .15s ease-in-out,background-color .15s ease-in-out,border-color .15s ease-in-out,box-shadow .15s ease-in-out;
}
.btn-primary {
  color: #fff;
  background-color: #007bff;
  border-color: #007bff;
}
.btn-secondary {
  color: #fff;
  background-color: #6c757d;
  border-color: #6c757d;
}
.mt-3 {
  margin-top: 1rem;
}
.mb-3 {
  margin-bottom: 1rem;
}
.w-100 {
  width: 100%;
}
.d-none {
  display: none;
}
.text-center {
  text-align: center;
}