refactor(styles): move common styles to shared CSS file

Extract duplicated styles across multiple components into a common CSS file and import it where needed. This improves maintainability by reducing code duplication and centralizing style definitions.

src/views/Instances.vue

@@ -136,21 +136,12 @@ export default {
 </script>
 
 <style scoped>
+@import '../styles/common.css';
+
 .instances-page {
     padding: 24px;
 }
 
-.page-header {
-    margin-bottom: 24px;
-}
-
-.page-header h2 {
-    font-size: 24px;
-    color: var(--text-color);
-    margin: 0;
-    transition: color 0.3s;
-}
-
 .instances-grid {
     display: grid;
     grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
@@ -158,10 +149,6 @@ export default {
 }
 
 .instance-card {
-    background: var(--card-bg);
-    border-radius: 8px;
-    padding: 20px;
-    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
     cursor: pointer;
     transition: all 0.3s;
 }
@@ -171,13 +158,6 @@ export default {
     box-shadow: 0 4px 16px rgba(0, 0, 0, 0.12);
 }
 
-.card-header {
-    display: flex;
-    justify-content: space-between;
-    align-items: center;
-    margin-bottom: 16px;
-}
-
 .instance-name {
     font-size: 18px;
     font-weight: 600;
@@ -185,85 +165,4 @@ export default {
     margin: 0;
     transition: color 0.3s;
 }
-
-.status-badge {
-    padding: 4px 12px;
-    border-radius: 12px;
-    font-size: 12px;
-    font-weight: 500;
-}
-
-.status-badge.running {
-    background: #f6ffed;
-    color: #52c41a;
-}
-
-.status-badge.stopped {
-    background: #fff1f0;
-    color: #ff4d4f;
-}
-
-.card-body {
-    display: flex;
-    flex-direction: column;
-    gap: 8px;
-    margin-bottom: 16px;
-}
-
-.info-row {
-    display: flex;
-    justify-content: space-between;
-    font-size: 14px;
-}
-
-.info-row .label {
-    color: #666;
-}
-
-.info-row .value {
-    color: var(--text-color);
-    font-weight: 500;
-    transition: color 0.3s;
-}
-
-.card-footer {
-    display: flex;
-    gap: 8px;
-}
-
-.action-btn {
-    flex: 1;
-    padding: 8px 16px;
-    border: none;
-    border-radius: 6px;
-    font-size: 14px;
-    font-weight: 500;
-    cursor: pointer;
-    transition: all 0.3s;
-}
-
-.start-btn {
-    background: #52c41a;
-    color: white;
-}
-
-.start-btn:hover {
-    background: #45a049;
-}
-
-.stop-btn {
-    background: #ff4d4f;
-    color: white;
-}
-
-.stop-btn:hover {
-    background: #f04142;
-}
-
-.empty-state {
-    text-align: center;
-    padding: 60px 20px;
-    color: #999;
-    font-size: 16px;
-}
 </style>