feat: Implement core application structure with frontend styling, JavaScript, and Python backend services.

frontend/style.css

@@ -999,6 +999,7 @@ select {
 .content-area {
   flex: 1;
   overflow-y: auto;
+  overflow-x: hidden;
   padding: clamp(16px, 3vw, 40px) clamp(16px, 4vw, 40px) 60px;
   transition:
     background 200ms ease,
@@ -4648,9 +4649,8 @@ body.popup-mode .content-area {
    --------------------------------------------------------------------------- */
 
 .dashboard-home {
-  padding: 24px;
-  height: 100%;
-  overflow-y: auto;
+  padding: 0;
+  width: 100%;
   display: flex;
   flex-direction: column;
 }
@@ -4713,9 +4713,10 @@ body.popup-mode .content-area {
 /* Grid */
 .dashboard-recent-grid {
   display: grid;
-  grid-template-columns: repeat(3, 1fr);
+  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
   gap: 16px;
   flex: 1;
+  width: 100%;
 }
 
 @media (max-width: 1200px) {
@@ -4743,13 +4744,13 @@ body.popup-mode .content-area {
   background: var(--bg-secondary);
   border: 1px solid var(--border);
   border-radius: 12px;
-  padding: 16px;
+  padding: 12px;
   cursor: pointer;
-  transition: all 0.2s ease;
+  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
   position: relative;
   display: flex;
   flex-direction: column;
-  gap: 8px;
+  gap: 4px;
   animation: fadeSlideIn 0.3s ease forwards;
   opacity: 0;
 }
@@ -4813,11 +4814,11 @@ body.popup-mode .content-area {
 }
 
 .dashboard-card-icon {
-  width: 36px;
-  height: 36px;
-  padding: 8px;
+  width: 28px;
+  height: 28px;
+  padding: 6px;
   background: var(--accent);
-  border-radius: 8px;
+  border-radius: 6px;
   color: white;
   flex-shrink: 0;
 }
@@ -4848,6 +4849,7 @@ body.popup-mode .content-area {
   text-overflow: ellipsis;
   display: -webkit-box;
   -webkit-line-clamp: 2;
+  line-clamp: 2;
   -webkit-box-orient: vertical;
 }
 
@@ -4863,15 +4865,7 @@ body.popup-mode .content-area {
 
 /* Card preview */
 .dashboard-card-preview {
-  font-size: 12px;
-  color: var(--text-muted);
-  line-height: 1.5;
-  display: -webkit-box;
-  -webkit-line-clamp: 2;
-  line-clamp: 2;
-  -webkit-box-orient: vertical;
-  overflow: hidden;
-  margin: 0;
+  display: none;
 }
 
 /* Card footer */
@@ -4880,9 +4874,9 @@ body.popup-mode .content-area {
   align-items: center;
   justify-content: space-between;
   gap: 8px;
-  margin-top: auto;
-  padding-top: 8px;
-  border-top: 1px solid var(--border);
+  margin-top: 4px;
+  padding-top: 6px;
+  border-top: 1px solid color-mix(in srgb, var(--border) 50%, transparent);
 }
 
 .dashboard-card-time {