/* ── SOURCE ARCHITECTURE 섹션의 두 책을 실제 표지로 교체 ── */
.source-flow .book{
  width:145px;
  height:207px;                 /* 표지 비율(약 1:1.43)에 맞춤 */
  padding:0;
  border-radius:3px;
  background-repeat:no-repeat;
  background-position:center;
  background-size:cover;
  box-shadow:0 12px 30px rgba(20,41,67,.28);
  position:relative;
  overflow:hidden;
}
.source-flow .book.b1{
  background-image:url("/intro/cover1.jpg");
  border-bottom:0;
}
.source-flow .book.b2{
  background-image:url("/intro/cover2.jpg");
  border-bottom:0;
}
/* 표지 위의 기존 텍스트는 숨기고, 하단에 얇은 캡션만 남긴다 */
.source-flow .book small,
.source-flow .book strong{ display:none; }
.source-flow .book span{
  position:absolute; left:0; right:0; bottom:0;
  background:linear-gradient(180deg,rgba(7,26,49,0),rgba(7,26,49,.92));
  color:#E7CE7E; font-size:8.5px; letter-spacing:.6px;
  text-align:center; padding:16px 6px 6px;
}
@media (max-width:760px){
  .source-flow .book{ width:118px; height:169px; }
}