First set of upgrades for the Panel component

src/myfasthtml/assets/myfasthtml.css

@@ -662,17 +662,29 @@
     position: relative;
 }
 
-.mf-panel-left {
+/* Common properties for side panels */
+.mf-panel-left,
+.mf-panel-right {
     position: relative;
     flex-shrink: 0;
     width: 250px;
     min-width: 150px;
-    max-width: 400px;
+    max-width: 500px;
     height: 100%;
     overflow: auto;
+    transition: width 0.3s ease, min-width 0.3s ease, max-width 0.3s ease;
+}
+
+/* Left panel specific */
+.mf-panel-left {
     border-right: 1px solid var(--color-border-primary);
 }
 
+/* Right panel specific */
+.mf-panel-right {
+    border-left: 1px solid var(--color-border-primary);
+}
+
 .mf-panel-main {
     flex: 1;
     height: 100%;
@@ -680,16 +692,50 @@
     min-width: 0; /* Important to allow the shrinking of flexbox */
 }
 
-.mf-panel-right {
-    position: relative;
-    flex-shrink: 0;
-    width: 300px;
-    min-width: 150px;
-    max-width: 500px;
-    height: 100%;
-    overflow: auto;
-    border-left: 1px solid var(--color-border-primary);
-    padding: 0.5rem;
+/* Hidden state - common for both panels */
+.mf-panel-left.mf-hidden,
+.mf-panel-right.mf-hidden {
+    width: 0;
+    min-width: 0;
+    max-width: 0;
+    overflow: hidden;
+    border: none;
+}
+
+/* No transition during manual resize - common for both panels */
+.mf-panel-left.no-transition,
+.mf-panel-right.no-transition {
+    transition: none;
+}
+
+/* Common properties for panel toggle icons */
+.mf-panel-hide-icon,
+.mf-panel-show-icon {
+    position: absolute;
+    top: 0.5rem;
+    cursor: pointer;
+    z-index: 10;
+    padding: 0.25rem;
+    border-radius: 0.25rem;
+}
+
+.mf-panel-hide-icon:hover,
+.mf-panel-show-icon:hover {
+    background-color: var(--color-bg-hover, rgba(0, 0, 0, 0.05));
+}
+
+/* Hide icon always on the right */
+.mf-panel-hide-icon {
+    right: 0.5rem;
+}
+
+/* Show icon positioning */
+.mf-panel-show-icon-left {
+    left: 0.5rem;
+}
+
+.mf-panel-show-icon-right {
+    right: 0.5rem;
 }
 
 /* *********************************************** */