feat: 개인 PC 수정 이력(Log) 시스템 구현 및 UI 개선

src/styles/modal.css

@@ -63,3 +63,99 @@
 }
 
 .footer-actions { display: flex; gap: 0.5rem; }
+
+/* Wide Modal for History */
+.modal-content.wide {
+  max-width: 950px;
+}
+
+.modal-body-split {
+  display: flex;
+  gap: 2rem;
+  min-height: 480px;
+}
+
+.modal-form-area {
+  flex: 1.2;
+}
+
+.modal-history-area {
+  flex: 0.8;
+  border-left: 1px solid var(--border-color);
+  padding-left: 1.5rem;
+  display: flex;
+  flex-direction: column;
+}
+
+.history-header {
+  margin-bottom: 1rem;
+}
+
+.history-header h3 {
+  font-size: 0.9375rem;
+  font-weight: 600;
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+  color: var(--text-main);
+}
+
+.history-timeline {
+  flex: 1;
+  overflow-y: auto;
+  max-height: 500px;
+  padding-right: 0.5rem;
+}
+
+.history-item {
+  position: relative;
+  padding-left: 1.25rem;
+  padding-bottom: 1.5rem;
+  border-left: 2px solid var(--border-color);
+}
+
+.history-item::before {
+  content: '';
+  position: absolute;
+  left: -7px;
+  top: 0;
+  width: 12px;
+  height: 12px;
+  border-radius: 50%;
+  background-color: var(--white);
+  border: 2px solid var(--primary-color);
+}
+
+.history-item:last-child {
+  border-left: 2px solid transparent;
+}
+
+.history-date {
+  font-size: 0.75rem;
+  color: var(--text-muted);
+  font-weight: 500;
+  margin-bottom: 0.25rem;
+}
+
+.history-user {
+  font-size: 0.75rem;
+  font-weight: 600;
+  color: var(--primary-color);
+  margin-bottom: 0.25rem;
+}
+
+.history-details {
+  font-size: 0.8125rem;
+  color: var(--text-main);
+  line-height: 1.4;
+  white-space: pre-wrap;
+  word-break: break-all;
+}
+
+.empty-history {
+  padding: 2rem 0;
+  text-align: center;
+  color: var(--text-muted);
+  font-size: 0.8125rem;
+}
+