:root {
            --primary-bg: #f3f4f6;
            --sidebar-bg: #ffffff;
            --text-main: #1e293b;
            --text-light: #64748b;
            --accent-teal: #0ea5e9;
            --card-hover: #e0f2fe;
            --border-color: #e2e8f0;
            --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }

        * { box-sizing: border-box; margin: 0; padding: 0; font-family: 'Vazirmatn', sans-serif; text-decoration: none; outline: none; -webkit-tap-highlight-color: transparent; }

        body { background-color: var(--primary-bg); color: var(--text-main); display: flex; height: 100vh; overflow: hidden; }

        /* --- Mobile Menu --- */
        .mobile-menu-btn { display: none; position: fixed; top: 20px; right: 20px; z-index: 1001; background: white; border: none; width: 45px; height: 45px; border-radius: 12px; box-shadow: 0 4px 15px rgba(0,0,0,0.1); color: var(--accent-teal); font-size: 20px; cursor: pointer; align-items: center; justify-content: center; }
        .overlay { display: none; position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0, 0, 0, 0.4); backdrop-filter: blur(2px); z-index: 1002; }
        .overlay.active { display: block; }

        /* --- Sidebar --- */
        .sidebar { width: 260px; background-color: var(--sidebar-bg); border-left: 1px solid var(--border-color); display: flex; flex-direction: column; padding: 20px; z-index: 1000; transition: transform 0.3s; flex-shrink: 0; height: 100vh; }
        .sidebar.active { transform: translateX(0); }
        .brand-logo { font-size: 22px; font-weight: 800; color: var(--accent-teal); display: flex; align-items: center; justify-content: center; gap: 10px; margin-bottom: 40px; padding-bottom: 20px; border-bottom: 1px solid #f1f5f9; }
        .nav-menu { display: flex; flex-direction: column; gap: 10px; flex: 1; overflow-y: auto; }
        .nav-item { display: flex; align-items: center; gap: 12px; padding: 12px 15px; border-radius: 12px; color: var(--text-light); font-weight: 500; font-size: 14px; transition: 0.2s; white-space: nowrap; }
        .nav-item:hover { background-color: #f1f5f9; color: var(--accent-teal); transform: translateX(-5px); }
        .nav-item i { width: 20px; text-align: center; font-size: 18px; }
        .sidebar-footer { margin-top: auto; border-top: 1px solid #f1f5f9; padding-top: 20px; display: flex; align-items: center; gap: 10px; }
        .user-avatar { width: 40px; height: 40px; background: #e0f2fe; color: #0284c7; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: bold; flex-shrink: 0; }

        /* --- Main Content --- */
        .main-content { flex: 1; padding: 30px; overflow-y: auto; display: flex; flex-direction: column; gap: 20px; scroll-behavior: smooth; }

        .page-header { display: flex; align-items: center; gap: 15px; margin-bottom: 10px; }
        .back-btn { width: 40px; height: 40px; border-radius: 50%; background: white; display: flex; align-items: center; justify-content: center; color: var(--text-main); box-shadow: 0 2px 5px rgba(0,0,0,0.1); transition: 0.2s; cursor: pointer; flex-shrink: 0; }
        .back-btn:hover { background-color: var(--accent-teal); color: white; transform: translateX(3px); }
        .page-title { font-size: 24px; font-weight: 800; color: var(--text-main); }

        /* --- Systems Grid --- */
        .systems-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
            gap: 20px;
        }

        .system-card {
            background: white;
            border: 1px solid var(--border-color);
            border-radius: 16px;
            padding: 20px;
            display: flex;
            align-items: center;
            gap: 20px;
            cursor: pointer;
            transition: var(--transition);
            position: relative;
            overflow: hidden;
            text-decoration: none; /* مهم برای تگ a */
            color: inherit;
        }

        /* نوار رنگی هوشمند */
        .system-card::before {
            content: '';
            position: absolute;
            right: 0; top: 0; bottom: 0;
            width: 5px;
            background-color: var(--accent-teal);
            opacity: 0;
            transition: 0.3s;
        }

        .system-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 20px -5px rgba(0, 0, 0, 0.1);
            border-color: var(--accent-teal);
        }

        .system-card:hover::before { opacity: 1; }

        .card-icon {
            width: 55px; height: 55px;
            background-color: #f1f5f9;
            border-radius: 14px;
            display: flex; align-items: center; justify-content: center;
            font-size: 24px;
            color: var(--text-light);
            transition: 0.3s;
            flex-shrink: 0;
        }

        .system-card:hover .card-icon {
            background-color: var(--accent-teal);
            color: white;
        }

        .card-info { flex: 1; min-width: 0; }
        .card-title { font-weight: 700; font-size: 15px; color: var(--text-main); margin-bottom: 5px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
        .card-subtitle { font-size: 13px; color: var(--text-light); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
        
        .external-link-icon { font-size: 14px; color: #cbd5e1; transition: 0.3s; }
        .system-card:hover .external-link-icon { color: var(--accent-teal); transform: translateX(-3px) translateY(-3px); }

        /* --- Responsive --- */
        @media (max-width: 768px) {
            body { display: block; overflow: auto; }
            .mobile-menu-btn { display: flex; }
            .sidebar { position: fixed; top: 0; right: 0; height: 100vh; width: 280px; transform: translateX(100%); box-shadow: -5px 0 20px rgba(0,0,0,0.1); z-index: 1003; }
            .sidebar.active { transform: translateX(0); }
            .main-content { padding: 80px 20px 20px 20px; height: auto; overflow: visible; }
            .systems-grid { grid-template-columns: 1fr; }
        }