Apply glassmorphism to ConfirmDialog overlay and surface

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/components/ConfirmDialog.vue

@@ -75,7 +75,7 @@ watch(
 .confirm-dialog__overlay {
   position: fixed;
   inset: 0;
-  background: rgba(0, 0, 0, 0.4);
+  background: var(--color-glass-overlay);
   display: flex;
   align-items: center;
   justify-content: center;
@@ -84,9 +84,12 @@ watch(
 }
 
 .confirm-dialog {
-  background: var(--color-card);
+  background: linear-gradient(135deg, var(--color-glass-strong) 0%, var(--color-glass-subtle) 100%);
+  border: 1px solid var(--color-glass-border);
+  backdrop-filter: blur(24px);
+  -webkit-backdrop-filter: blur(24px);
   border-radius: var(--radius-card);
-  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
+  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
   padding: var(--spacing-xl);
   max-width: 320px;
   width: 100%;
@@ -98,13 +101,13 @@ watch(
 .confirm-dialog__title {
   font-size: 1.05rem;
   font-weight: 700;
-  color: var(--color-text);
+  color: var(--color-text-on-gradient);
 }
 
 .confirm-dialog__message {
   font-size: 0.9rem;
   font-weight: 400;
-  color: #666;
+  color: var(--color-text-soft);
 }
 
 .confirm-dialog__actions {
@@ -130,8 +133,9 @@ watch(
 }
 
 .confirm-dialog__btn--cancel {
-  background: #e8e8e8;
-  color: #555;
+  background: var(--color-glass);
+  border: 1px solid var(--color-glass-border);
+  color: var(--color-text-on-gradient);
 }
 
 .confirm-dialog__btn--confirm {