restore frontend base structure and style.css + modal

backend/public/css/style.css

@@ -1,5 +1,5 @@
 body {
-font-family:Arial;
+    font-family: Arial, sans-serif;
     margin: 40px;
     background: #f4f6f8;
 }
@@ -13,8 +13,8 @@ background:white;
     padding: 20px;
     margin-bottom: 30px;
     border-radius: 8px;
-box-shadow:0 2px 6px rgba(0,0,0,0.1);
     border-left: 4px solid #3b82f6;
+    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
 }
 
 table {
@@ -34,6 +34,10 @@ background:#1e3a8a;
     color: white;
 }
 
+td {
+    vertical-align: top;
+}
+
 button {
     background: #3b82f6;
     color: white;
@@ -48,6 +52,12 @@ button:hover{
     background: #1e40af;
 }
 
+input, textarea {
+    padding: 6px;
+    margin: 4px;
+    width: 95%;
+}
+
 .provider {
     background: #e9f2ff;
     padding: 2px 8px;
@@ -59,7 +69,7 @@ font-size:12px;
     font-size: 12px;
     background: #f4f4f4;
     padding: 2px 6px;
-margin:2px 0;
+    margin: 2px;
     border-radius: 4px;
     display: inline-block;
 }
@@ -68,3 +78,18 @@ display:inline-block;
     font-size: 13px;
     color: #333;
 }
+
+.modal {
+    display: none;
+    position: fixed;
+    top: 10%;
+    left: 50%;
+    transform: translateX(-50%);
+    background: white;
+    padding: 20px;
+    width: 600px;
+    max-height: 80vh;
+    overflow: auto;
+    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
+    border-radius: 6px;
+}