fix(FN-1306): improve PlanningModeModal layout for mobile screens

- Move model selector from sticky footer into scrollable content area
- Slim the footer to only contain the Start Planning button
- Add .planning-model-select-group CSS for proper flexbox layout
- Center footer button and model-select row for better mobile UX
- Remove inline styles from model selector, use CSS classes instead

packages/dashboard/app/components/PlanningModeModal.tsx

@@ -752,19 +752,9 @@ export function PlanningModeModal({ isOpen, onClose, onTaskCreated, onTasksCreat
                     ))}
                   </div>
                 </div>
-              </div>
 
-              <div className="planning-view-footer">
-                <div
-                  className="model-select-row"
-                  style={{
-                    marginRight: "auto",
-                    minWidth: "min(100%, 320px)",
-                    maxWidth: "420px",
-                    textAlign: "left",
-                  }}
-                >
-                  <label htmlFor="planning-modal-model" className="model-select-label">
+                <div className="planning-model-select-group">
+                  <label htmlFor="planning-modal-model" className="form-label">
                     Planning Model
                     {modelsLoading && (
                       <span className="text-muted" style={{ marginLeft: "8px", fontSize: "12px" }}>
@@ -822,7 +812,9 @@ export function PlanningModeModal({ isOpen, onClose, onTaskCreated, onTasksCreat
                     </span>
                   </div>
                 </div>
+              </div>
 
+              <div className="planning-view-footer">
                 <button
                   className="btn btn-primary planning-start-btn"
                   onClick={() => handleStartPlanning()}

packages/dashboard/app/styles.css

@@ -13888,12 +13888,27 @@ body[data-color-theme="terminal"][data-theme="light"]::before {
 
 .planning-view-footer {
   display: flex;
-  justify-content: flex-end;
+  justify-content: center;
   padding: 16px 24px 24px;
   border-top: 1px solid var(--border);
   flex-shrink: 0;
 }
 
+.planning-model-select-group {
+  display: flex;
+  flex-direction: column;
+  gap: var(--space-sm);
+  max-width: 420px;
+  margin: 0 auto;
+  width: 100%;
+}
+
+.planning-model-select-group .form-label {
+  font-size: 13px;
+  color: var(--text-muted);
+  text-align: left;
+}
+
 .session-lock-overlay {
   position: absolute;
   inset: 0;
@@ -14059,6 +14074,7 @@ body[data-color-theme="terminal"][data-theme="light"]::before {
   width: 100%;
   max-width: 568px;
   margin: 0 auto;
+  justify-content: center;
 }
 
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