diff --git a/frontend/src/App.css b/frontend/src/App.css
new file mode 100644
index 0000000..2eebdde
--- /dev/null
+++ b/frontend/src/App.css
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+* {
+  margin: 0;
+  padding: 0;
+  box-sizing: border-box;
+}
+
+:root {
+  --color-primary: #2563eb;
+  --color-secondary: #64748b;
+  --color-success: #10b981;
+  --color-danger: #ef4444;
+  --color-warning: #f59e0b;
+  --color-bg-dark: #0f172a;
+  --color-bg-light: #f8fafc;
+  --color-border: #e2e8f0;
+  --color-text-dark: #1e293b;
+  --color-text-light: #64748b;
+  --radius-sm: 4px;
+  --radius-md: 8px;
+  --radius-lg: 12px;
+  --spacing-xs: 4px;
+  --spacing-sm: 8px;
+  --spacing-md: 16px;
+  --spacing-lg: 24px;
+  --spacing-xl: 32px;
+}
+
+body {
+  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
+    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
+  background-color: var(--color-bg-light);
+  color: var(--color-text-dark);
+  -webkit-font-smoothing: antialiased;
+  -moz-osx-font-smoothing: grayscale;
+}
+
+/* App Layout */
+.app-container {
+  display: flex;
+  flex-direction: column;
+  height: 100vh;
+  overflow: hidden;
+  background: var(--color-bg-light);
+}
+
+.app-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: var(--spacing-lg);
+  background: linear-gradient(135deg, var(--color-primary) 0%, #1d4ed8 100%);
+  color: white;
+  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
+  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
+}
+
+.header-content h1 {
+  font-size: 1.75rem;
+  font-weight: 700;
+  margin-bottom: var(--spacing-xs);
+}
+
+.header-content p {
+  font-size: 0.875rem;
+  opacity: 0.9;
+}
+
+.system-status {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-md);
+  font-size: 0.875rem;
+}
+
+.status-indicator {
+  display: inline-block;
+  width: 8px;
+  height: 8px;
+  border-radius: 50%;
+  background-color: rgba(255, 255, 255, 0.3);
+}
+
+.status-indicator.running {
+  background-color: #10b981;
+  animation: pulse 2s infinite;
+}
+
+@keyframes pulse {
+  0% {
+    opacity: 1;
+  }
+  50% {
+    opacity: 0.5;
+  }
+  100% {
+    opacity: 1;
+  }
+}
+
+/* Main Content */
+.app-main {
+  display: flex;
+  flex: 1;
+  overflow: hidden;
+  gap: 1px;
+  background: var(--color-border);
+}
+
+.sidebar {
+  width: 320px;
+  background: white;
+  border-right: 1px solid var(--color-border);
+  overflow-y: auto;
+  padding: var(--spacing-lg);
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-md);
+}
+
+.btn {
+  padding: var(--spacing-md) var(--spacing-lg);
+  border: none;
+  border-radius: var(--radius-md);
+  font-size: 0.875rem;
+  font-weight: 600;
+  cursor: pointer;
+  transition: all 0.2s ease;
+  text-decoration: none;
+  display: inline-flex;
+  align-items: center;
+  gap: var(--spacing-sm);
+}
+
+.btn-primary {
+  background: var(--color-primary);
+  color: white;
+}
+
+.btn-primary:hover {
+  background: #1d4ed8;
+  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
+}
+
+.btn-secondary {
+  background: var(--color-secondary);
+  color: white;
+}
+
+.btn-secondary:hover {
+  background: #475569;
+}
+
+.btn-success {
+  background: var(--color-success);
+  color: white;
+}
+
+.btn-success:hover {
+  background: #059669;
+}
+
+.btn-danger {
+  background: var(--color-danger);
+  color: white;
+}
+
+.btn-danger:hover {
+  background: #dc2626;
+}
+
+.btn-create {
+  width: 100%;
+  justify-content: center;
+  font-size: 1rem;
+}
+
+.btn:disabled {
+  opacity: 0.6;
+  cursor: not-allowed;
+}
+
+.tasks-list {
+  flex: 1;
+  overflow-y: auto;
+}
+
+.tasks-list h2 {
+  font-size: 0.875rem;
+  font-weight: 700;
+  text-transform: uppercase;
+  color: var(--color-text-light);
+  margin-bottom: var(--spacing-md);
+  margin-top: var(--spacing-lg);
+}
+
+.task-item {
+  padding: var(--spacing-md);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-md);
+  cursor: pointer;
+  transition: all 0.2s ease;
+  margin-bottom: var(--spacing-sm);
+}
+
+.task-item:hover {
+  border-color: var(--color-primary);
+  background: rgba(37, 99, 235, 0.03);
+}
+
+.task-item.active {
+  border-color: var(--color-primary);
+  background: rgba(37, 99, 235, 0.08);
+}
+
+.task-item-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: flex-start;
+  gap: var(--spacing-md);
+  margin-bottom: var(--spacing-sm);
+}
+
+.task-item h3 {
+  font-size: 0.875rem;
+  font-weight: 600;
+  flex: 1;
+}
+
+.status-badge {
+  padding: 2px 8px;
+  border-radius: var(--radius-sm);
+  color: white;
+  font-size: 0.75rem;
+  font-weight: 600;
+  text-transform: capitalize;
+  white-space: nowrap;
+}
+
+.task-schedule {
+  font-size: 0.75rem;
+  color: var(--color-text-light);
+  margin-bottom: 4px;
+}
+
+.task-last-run {
+  font-size: 0.75rem;
+  color: var(--color-text-light);
+}
+
+.empty-state {
+  padding: var(--spacing-lg);
+  text-align: center;
+  color: var(--color-text-light);
+  font-size: 0.875rem;
+}
+
+/* Content Area */
+.content {
+  flex: 1;
+  overflow-y: auto;
+  background: white;
+  padding: var(--spacing-xl);
+}
+
+.form-container {
+  max-width: 600px;
+}
+
+.form-container h2 {
+  font-size: 1.5rem;
+  margin-bottom: var(--spacing-lg);
+}
+
+.task-form {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-lg);
+}
+
+.form-group {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-sm);
+}
+
+.form-group label {
+  font-weight: 600;
+  font-size: 0.875rem;
+  color: var(--color-text-dark);
+}
+
+.form-group input,
+.form-group textarea,
+.form-group select {
+  padding: var(--spacing-md);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-md);
+  font-size: 0.875rem;
+  font-family: inherit;
+  transition: border-color 0.2s;
+}
+
+.form-group input:focus,
+.form-group textarea:focus,
+.form-group select:focus {
+  outline: none;
+  border-color: var(--color-primary);
+  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
+}
+
+.form-row {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: var(--spacing-lg);
+}
+
+.form-group.checkbox {
+  flex-direction: row;
+  align-items: center;
+  gap: var(--spacing-md);
+}
+
+.form-group.checkbox input {
+  width: auto;
+}
+
+.form-actions {
+  display: flex;
+  gap: var(--spacing-md);
+  margin-top: var(--spacing-lg);
+}
+
+.form-actions button {
+  flex: 1;
+}
+
+/* Task Detail */
+.task-detail {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-lg);
+}
+
+.task-detail-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: flex-start;
+  border-bottom: 1px solid var(--color-border);
+  padding-bottom: var(--spacing-lg);
+}
+
+.task-detail-header h2 {
+  font-size: 1.75rem;
+}
+
+.task-actions {
+  display: flex;
+  gap: var(--spacing-md);
+}
+
+.task-meta {
+  display: grid;
+  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
+  gap: var(--spacing-lg);
+  padding: var(--spacing-lg);
+  background: var(--color-bg-light);
+  border-radius: var(--radius-md);
+}
+
+.meta-item {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-sm);
+}
+
+.meta-item .label {
+  font-size: 0.75rem;
+  font-weight: 700;
+  text-transform: uppercase;
+  color: var(--color-text-light);
+}
+
+.meta-item .value {
+  font-size: 0.875rem;
+  font-weight: 600;
+}
+
+.task-section {
+  border-top: 1px solid var(--color-border);
+  padding-top: var(--spacing-lg);
+}
+
+.task-section h3 {
+  font-size: 1rem;
+  margin-bottom: var(--spacing-md);
+}
+
+.prompt-display {
+  background: var(--color-bg-light);
+  padding: var(--spacing-md);
+  border-radius: var(--radius-md);
+  overflow-x: auto;
+  border: 1px solid var(--color-border);
+  font-size: 0.875rem;
+  line-height: 1.5;
+}
+
+/* Run History */
+.runs-list {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-md);
+}
+
+.run-item {
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-md);
+  padding: var(--spacing-md);
+}
+
+.run-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  margin-bottom: var(--spacing-md);
+}
+
+.run-status {
+  padding: 4px 12px;
+  border-radius: var(--radius-sm);
+  font-size: 0.75rem;
+  font-weight: 600;
+  text-transform: uppercase;
+}
+
+.run-status.completed {
+  background: rgba(16, 185, 129, 0.2);
+  color: var(--color-success);
+}
+
+.run-status.failed {
+  background: rgba(239, 68, 68, 0.2);
+  color: var(--color-danger);
+}
+
+.run-status.running {
+  background: rgba(37, 99, 235, 0.2);
+  color: var(--color-primary);
+}
+
+.run-time {
+  font-size: 0.75rem;
+  color: var(--color-text-light);
+}
+
+.run-item details {
+  cursor: pointer;
+}
+
+.run-item summary {
+  padding: var(--spacing-sm);
+  cursor: pointer;
+  font-weight: 600;
+  font-size: 0.875rem;
+}
+
+.run-item pre {
+  background: var(--color-bg-light);
+  padding: var(--spacing-md);
+  border-radius: var(--radius-md);
+  overflow-x: auto;
+  font-size: 0.75rem;
+  margin-top: var(--spacing-sm);
+  border: 1px solid var(--color-border);
+}
+
+.run-item pre.error {
+  border-left: 3px solid var(--color-danger);
+}
+
+/* Empty States */
+.empty-state-main {
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
+  align-items: center;
+  height: 100%;
+  gap: var(--spacing-md);
+  color: var(--color-text-light);
+  text-align: center;
+}
+
+.empty-state-main h2 {
+  font-size: 1.25rem;
+  color: var(--color-text-dark);
+}
+
+.empty {
+  padding: var(--spacing-lg);
+  text-align: center;
+  color: var(--color-text-light);
+  font-size: 0.875rem;
+}
+
+/* Scrollbar Styling */
+::-webkit-scrollbar {
+  width: 8px;
+  height: 8px;
+}
+
+::-webkit-scrollbar-track {
+  background: transparent;
+}
+
+::-webkit-scrollbar-thumb {
+  background: var(--color-border);
+  border-radius: 4px;
+}
+
+::-webkit-scrollbar-thumb:hover {
+  background: #cbd5e1;
+}
+
+/* Responsive */
+@media (max-width: 768px) {
+  .app-main {
+    flex-direction: column;
+  }
+
+  .sidebar {
+    width: 100%;
+    border-right: none;
+    border-bottom: 1px solid var(--color-border);
+    max-height: 50vh;
+  }
+
+  .content {
+    padding: var(--spacing-lg);
+  }
+
+  .task-detail-header {
+    flex-direction: column;
+    gap: var(--spacing-md);
+  }
+
+  .task-actions {
+    width: 100%;
+  }
+
+  .task-actions button {
+    flex: 1;
+  }
+
+  .form-row {
+    grid-template-columns: 1fr;
+  }
+}