.trust-section {
  padding: 120px 0;
}
.trust-grid {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 80px;
  align-items: start;
}

/* Professor */
.trust-professor {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 40px;
  align-items: start;
}
.prof-photo {
  position: relative;
  aspect-ratio: 4 / 5;
}
.prof-photo-inner {
  position: absolute;
  inset: 0;
  z-index: 2;
}
.prof-photo-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 20%;
  z-index: 2;
  background: var(--paper-2);
  border: 1px solid var(--line);
}
.prof-photo-frame {
  position: absolute;
  top: 16px;
  left: 16px;
  right: -16px;
  bottom: -16px;
  border: 1px solid var(--gold);
  z-index: 1;
}

.prof-info .eyebrow { margin-bottom: 12px; }
.prof-name {
  font-family: var(--serif);
  font-size: 32px;
  color: var(--navy);
  margin: 0 0 8px;
  letter-spacing: -0.02em;
  font-weight: 500;
}
.prof-title {
  font-size: 14px;
  color: var(--ink-2);
  padding-bottom: 20px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 20px;
}
.prof-credentials {
  list-style: none;
  padding: 0;
  margin: 0 0 32px;
}
.prof-credentials li {
  font-size: 14px;
  color: var(--ink-2);
  margin-bottom: 10px;
  display: flex;
  gap: 8px;
  line-height: 1.6;
}
.pc-mark {
  color: var(--gold);
  font-weight: 700;
}

.prof-sig {
  margin-top: 24px;
}
.sig-placeholder {
  width: 180px;
  height: 60px;
}

/* Right side */
.trust-side {
  display: flex;
  flex-direction: column;
  gap: 20px;
}
.trust-card {
  background: white;
  border: 1px solid var(--line-soft);
  padding: 24px;
  display: flex;
  gap: 20px;
  align-items: center;
  box-shadow: var(--shadow-sm);
}

.book-cover {
  width: 96px;
  height: 128px;
  flex-shrink: 0;
  border: 1px solid var(--navy);
  box-shadow: 4px 4px 0 var(--paper-3);
}
.book-cover-img {
  width: 96px;
  height: 128px;
  flex-shrink: 0;
  object-fit: cover;
  border: 1px solid var(--line);
  box-shadow: 4px 4px 0 var(--paper-3), var(--shadow-sm);
  display: block;
}
.book-title, .qr-title {
  font-size: 18px;
  color: var(--navy);
  margin: 6px 0 6px;
  font-weight: 500;
}
.book-sub, .qr-sub {
  font-size: 13px;
  color: var(--ink-2);
  line-height: 1.6;
}

/* QR 카드 · 클릭 가능한 링크로 업그레이드 */
a.qr-card {
  text-decoration: none;
  color: inherit;
  transition: all 260ms cubic-bezier(0.2, 0.7, 0.2, 1);
  cursor: pointer;
}
a.qr-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
  border-color: var(--gold);
}
a.qr-card:hover .qr-frame {
  border-color: var(--gold);
}
a.qr-card:hover .qr-corner {
  border-color: var(--gold);
}
a.qr-card:hover .qr-title {
  color: var(--gold-soft);
}
.qr-ext {
  display: inline-block;
  margin-left: 3px;
  font-size: 10px;
  color: var(--gold);
  transition: transform 220ms cubic-bezier(0.2, 0.7, 0.2, 1);
}
a.qr-card:hover .qr-ext {
  transform: translate(2px, -2px);
}

/* QR */
.qr-frame {
  position: relative;
  width: 110px;
  height: 110px;
  flex-shrink: 0;
  padding: 6px;
  background: white;
  border: 1px solid var(--line);
}
.qr-ph {
  width: 100%;
  height: 100%;
}
.qr-img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}
.qr-corner {
  position: absolute;
  width: 14px;
  height: 14px;
  border: 2px solid var(--navy);
}
.qr-corner.tl { top: -1px; left: -1px; border-right: none; border-bottom: none; }
.qr-corner.tr { top: -1px; right: -1px; border-left: none; border-bottom: none; }
.qr-corner.bl { bottom: -1px; left: -1px; border-right: none; border-top: none; }
.qr-corner.br { bottom: -1px; right: -1px; border-left: none; border-top: none; }

/* Badges */
.trust-badges {
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 28px;
  background: var(--navy-deep);
  color: var(--paper);
  justify-content: space-between;
}
.tb {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.tb-num {
  font-family: var(--serif);
  font-size: 30px;
  color: var(--gold);
  line-height: 1;
  font-weight: 500;
}
.tb-num sup {
  font-size: 12px;
  color: #b8c5d1;
  font-weight: 400;
  margin-left: 2px;
}
.tb-lbl {
  font-size: 11px;
  letter-spacing: 0.08em;
  color: #b8c5d1;
  text-transform: uppercase;
}
.tb-sep {
  width: 1px;
  height: 32px;
  background: rgba(212,175,55,0.3);
}

@media (max-width: 1000px) {
  .trust-grid { grid-template-columns: 1fr; gap: 40px; }
  .trust-professor { grid-template-columns: 180px 1fr; gap: 24px; }
}
@media (max-width: 640px) {
  .trust-professor { grid-template-columns: 1fr; }
  .prof-photo { max-width: 240px; }
  .trust-card { flex-direction: column; text-align: center; }
  .trust-badges { flex-direction: column; gap: 20px; }
  .tb-sep { width: 32px; height: 1px; }
}