* {
     box-sizing: border-box;
     margin: 0;
     padding: 0;
 }

 body {
     font-family: 'Inter', sans-serif;
     background: linear-gradient(135deg, #0f0c29, #302b63, #24243e);
     min-height: 100vh;
     color: #e0e0e0;
     padding: 20px;
 }

 .container {
     max-width: 960px;
     margin: 0 auto;
 }

 .header {
     text-align: center;
     padding: 30px 0 20px;
 }

 .header h1 {
     font-size: 2rem;
     font-weight: 700;
     background: linear-gradient(90deg, #f7971e, #ffd200);
     -webkit-background-clip: text;
     -webkit-text-fill-color: transparent;
     margin-bottom: 8px;
 }

 .header p {
     color: #aaa;
     font-size: 0.9rem;
 }

 /* Tabs */
 .tabs {
     display: flex;
     gap: 4px;
     margin-bottom: 0;
     overflow-x: auto;
 }

 .tab-btn {
     padding: 12px 20px;
     border: none;
     background: rgba(255, 255, 255, 0.06);
     color: #aaa;
     cursor: pointer;
     font-family: inherit;
     font-size: 0.85rem;
     font-weight: 500;
     border-radius: 12px 12px 0 0;
     transition: all 0.2s;
     white-space: nowrap;
 }

 .tab-btn:hover {
     background: rgba(255, 255, 255, 0.1);
     color: #fff;
 }

 .tab-btn.active {
     background: rgba(255, 255, 255, 0.12);
     color: #ffd200;
     border-bottom: 2px solid #ffd200;
 }

 /* Card */
 .card {
     background: rgba(255, 255, 255, 0.08);
     backdrop-filter: blur(20px);
     border: 1px solid rgba(255, 255, 255, 0.1);
     border-radius: 0 16px 16px 16px;
     padding: 28px;
     margin-bottom: 20px;
 }

 .card h3 {
     font-size: 1.1rem;
     font-weight: 600;
     color: #ffd200;
     margin-bottom: 6px;
 }

 .card .desc {
     color: #999;
     font-size: 0.82rem;
     margin-bottom: 20px;
 }

 /* Form */
 .form-group {
     margin-bottom: 14px;
 }

 .form-group label {
     display: block;
     font-size: 0.8rem;
     font-weight: 500;
     color: #bbb;
     margin-bottom: 5px;
 }

 .form-group input,
 .form-group textarea {
     width: 100%;
     padding: 10px 14px;
     background: rgba(0, 0, 0, 0.3);
     border: 1px solid rgba(255, 255, 255, 0.12);
     border-radius: 8px;
     color: #e0e0e0;
     font-family: 'Inter', monospace;
     font-size: 0.85rem;
     outline: none;
     transition: border-color 0.2s;
 }

 .form-group input:focus,
 .form-group textarea:focus {
     border-color: #ffd200;
 }

 .form-group textarea {
     min-height: 80px;
     resize: vertical;
 }

 .form-row {
     display: grid;
     grid-template-columns: 1fr 1fr;
     gap: 12px;
 }

 /* Buttons */
 .btn {
     padding: 10px 22px;
     border: none;
     border-radius: 8px;
     cursor: pointer;
     font-family: inherit;
     font-size: 0.85rem;
     font-weight: 600;
     transition: all 0.2s;
 }

 .btn-primary {
     background: linear-gradient(135deg, #f7971e, #ffd200);
     color: #1a1a2e;
 }

 .btn-primary:hover {
     transform: translateY(-1px);
     box-shadow: 0 4px 20px rgba(255, 210, 0, 0.3);
 }

 .btn-primary:active {
     transform: translateY(0);
 }

 .btn-secondary {
     background: rgba(255, 255, 255, 0.1);
     color: #ccc;
 }

 .btn-secondary:hover {
     background: rgba(255, 255, 255, 0.15);
 }

 .btn-group {
     display: flex;
     gap: 10px;
     margin-top: 18px;
 }

 /* Tab Panels */
 .tab-panel {
     display: none;
 }

 .tab-panel.active {
     display: block;
 }

 /* Response */
 .response-area {
     background: rgba(0, 0, 0, 0.4);
     border: 1px solid rgba(255, 255, 255, 0.08);
     border-radius: 12px;
     padding: 20px;
     margin-top: 20px;
 }

 .response-area h4 {
     font-size: 0.85rem;
     color: #888;
     margin-bottom: 10px;
 }

 .log-box {
     background: #0d0d1a;
     border-radius: 8px;
     padding: 14px;
     max-height: 300px;
     overflow-y: auto;
     font-family: 'Courier New', monospace;
     font-size: 0.78rem;
     line-height: 1.6;
 }

 .log-entry {
     padding: 3px 0;
     border-bottom: 1px solid rgba(255, 255, 255, 0.04);
 }

 .log-entry.success {
     color: #4caf50;
 }

 .log-entry.error {
     color: #f44336;
 }

 .log-entry.info {
     color: #64b5f6;
 }

 .log-entry.warn {
     color: #ffa726;
 }

 /* JSON preview */
 .json-preview {
     background: #0d0d1a;
     border-radius: 8px;
     padding: 14px;
     font-family: 'Courier New', monospace;
     font-size: 0.78rem;
     color: #81c784;
     max-height: 250px;
     overflow-y: auto;
     white-space: pre-wrap;
     margin-top: 10px;
 }

 /* Status badge */
 .badge {
     display: inline-block;
     padding: 3px 10px;
     border-radius: 20px;
     font-size: 0.72rem;
     font-weight: 600;
 }

 .badge-ok {
     background: rgba(76, 175, 80, 0.2);
     color: #4caf50;
 }

 .badge-err {
     background: rgba(244, 67, 54, 0.2);
     color: #f44336;
 }

 .badge-pending {
     background: rgba(255, 167, 38, 0.2);
     color: #ffa726;
 }

 .section-label {
     font-size: 0.75rem;
     text-transform: uppercase;
     letter-spacing: 1px;
     color: #666;
     margin: 16px 0 8px;
     font-weight: 600;
 }

 /* FCM Status */
 .fcm-status {
     display: flex;
     align-items: center;
     gap: 10px;
     padding: 12px 16px;
     background: rgba(255, 255, 255, 0.04);
     border-radius: 8px;
     margin-bottom: 16px;
     font-size: 0.82rem;
 }

 @media (max-width: 600px) {
     .form-row {
         grid-template-columns: 1fr;
     }

     .tabs {
         flex-wrap: wrap;
     }
 }