.summary {
    display: flex;
    flex-wrap: wrap;
    align-items: flex-start
}
.summary .image {
    flex: 0 0 250px;
    margin-right: 40px;
}
.summary .image IMG {
    width: 100%;
    height: 100%;
    object-fit: cover;
}
.summary .text {
    flex: 1;
}
.summary .text p {
    line-height: 1.5em;
    word-wrap: break-word;
    word-break: auto-phrase;
}
.summary .text p br {
    line-height: 3em;
}
.category-item {
    display: inline-block;
    padding: 0 20px;
    line-height: 2em;
    font-size: 1em;
    background-color: #1f5da6;
    color: #fff;
    border-radius: 1em;
}
.btn_block {
    text-align: center;
}
.back_btn {
  position: relative;
  display: inline-block;
  width: 250px;
  margin: auto;
  margin-bottom: 1em;
  padding: 1em 0.5em;
  background-color: #1f5da6;
  color: #fff;
  border-radius: 5px;
  text-decoration: none;
}
.back_btn::before {
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  right: 1.5em;
  margin: auto;
  width: 0.6em;
  height: 1em;
  background-image: url('../img/top/white_arrow.png');
  background-repeat: no-repeat;
  background-size: cover;
}

@media (max-width: 768px) {
    .page-container .content {
        margin-top: 20px;
    } 
}

@media (max-width: 480px) {
    .page-container .subject h1 {
        font-size: 20px;
        line-height: 1.5;
    }
    .page-container .content {
        margin-top: 40px;
    }
    .summary .image {
        margin-right: auto;
        margin-left: auto;
    }
    .summary .text .category {
        margin-top: 22px;
        text-align: center;
    }
}