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

        body {
            font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
            background-color: #f8fafc;
            color: #0f172a;
            line-height: 1.5;
        }

        .container {
            max-width: 1280px;
            margin: 0 auto;
            padding: 0 24px;
        }

        .header {
            background-color: #ffffff;
            box-shadow: 0 1px 3px rgba(0,0,0,0.05);
            position: sticky;
            top: 0;
            z-index: 50;
            border-bottom: 1px solid #e2e8f0;
        }

        .nav {
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            padding: 1rem 0;
        }

        .logo a {
            font-size: 1.5rem;
            font-weight: 700;
            background: linear-gradient(135deg, #2563eb, #1e40af);
            background-clip: text;
            -webkit-background-clip: text;
            color: transparent;
            text-decoration: none;
            letter-spacing: -0.3px;
        }

        .nav-links {
            display: flex;
            gap: 2rem;
            align-items: center;
            flex-wrap: wrap;
        }

        .nav-links a {
            text-decoration: none;
            font-weight: 500;
            color: #1e293b;
            transition: color 0.2s;
        }

        .nav-links a:hover {
            color: #2563eb;
        }

        .btn-subscribe {
            background-color: #2563eb;
            color: white !important;
            padding: 0.5rem 1.25rem;
            border-radius: 40px;
            transition: background 0.2s;
        }

        .btn-subscribe:hover {
            background-color: #1d4ed8;
        }

        .page-header {
            text-align: center;
            padding: 3rem 0 1rem;
        }

        .page-header h1 {
            font-size: 2.6rem;
            font-weight: 800;
            background: linear-gradient(135deg, #0f172a, #2563eb);
            background-clip: text;
            -webkit-background-clip: text;
            color: transparent;
            margin-bottom: 1rem;
        }

        .page-header p {
            font-size: 1.2rem;
            color: #334155;
            max-width: 700px;
            margin: 0 auto;
        }

        .faq-search {
            margin: 2rem auto 2rem;
            max-width: 550px;
        }

        .search-box {
            display: flex;
            background: white;
            border-radius: 60px;
            border: 1px solid #e2e8f0;
            overflow: hidden;
            box-shadow: 0 2px 6px rgba(0,0,0,0.02);
        }

        .search-box input {
            flex: 1;
            padding: 0.85rem 1.5rem;
            border: none;
            font-size: 1rem;
            outline: none;
            background: transparent;
        }

        .search-box button {
            background: #2563eb;
            border: none;
            padding: 0 1.8rem;
            color: white;
            font-weight: 600;
            cursor: pointer;
            transition: background 0.2s;
            font-size: 0.95rem;
        }

        .search-box button:hover {
            background: #1e40af;
        }

        .faq-categories {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 0.8rem;
            margin: 1.5rem 0 2.5rem;
        }

        .cat-btn {
            background: #f1f5f9;
            border: none;
            padding: 0.5rem 1.3rem;
            border-radius: 40px;
            font-weight: 500;
            cursor: pointer;
            transition: all 0.2s;
            color: #1e293b;
        }

        .cat-btn.active {
            background: #2563eb;
            color: white;
        }

        .faq-list {
            max-width: 900px;
            margin: 0 auto 4rem;
        }

        .faq-item {
            background: white;
            border-radius: 1.25rem;
            margin-bottom: 1rem;
            border: 1px solid #eef2ff;
            transition: all 0.2s;
            overflow: hidden;
        }

        .faq-question {
            padding: 1.2rem 1.8rem;
            font-weight: 600;
            font-size: 1.05rem;
            cursor: pointer;
            display: flex;
            justify-content: space-between;
            align-items: center;
            background: #ffffff;
            transition: background 0.2s;
        }

        .faq-question:hover {
            background: #f8fafc;
        }

        .faq-question .q-icon {
            color: #2563eb;
            font-weight: 700;
            margin-right: 0.75rem;
        }

        .faq-question .toggle-icon {
            font-size: 1.3rem;
            color: #64748b;
        }

        .faq-answer {
            padding: 0 1.8rem 1.2rem 1.8rem;
            border-top: 1px solid #eef2ff;
            color: #334155;
            line-height: 1.6;
            display: none;
        }

        .faq-answer.show {
            display: block;
        }

        .faq-answer a {
            color: #2563eb;
            text-decoration: none;
        }

        .faq-answer a:hover {
            text-decoration: underline;
        }

        .faq-answer code {
            background: #f1f5f9;
            padding: 0.2rem 0.4rem;
            border-radius: 8px;
            font-size: 0.9rem;
        }

        .no-results {
            text-align: center;
            padding: 3rem;
            background: white;
            border-radius: 1.5rem;
            color: #475569;
        }

        .footer {
            border-top: 1px solid #e2e8f0;
            background: #f9fafb;
            padding: 2rem 0;
            margin-top: 2rem;
            text-align: center;
            color: #475569;
        }

        .footer-links {
            display: flex;
            justify-content: center;
            gap: 2rem;
            flex-wrap: wrap;
            margin-bottom: 1rem;
        }

        .footer-links a {
            text-decoration: none;
            color: #334155;
        }

        .footer-links a:hover {
            color: #2563eb;
        }

        @media (max-width: 768px) {
            .nav {
                flex-direction: column;
                gap: 1rem;
            }
            .faq-question {
                padding: 1rem;
                font-size: 0.95rem;
            }
            .faq-answer {
                padding: 0 1rem 1rem 1rem;
            }
        }
        .quick-diagnostic {
            background: linear-gradient(135deg, #f0f9ff 0%, #e6f0fa 100%);
            border-radius: 1.8rem;
            padding: 1.8rem;
            margin: 2rem 0;
            border: 1px solid #cbdff2;
        }
        .diag-title {
            font-size: 1.5rem;
            font-weight: 700;
            margin-bottom: 1rem;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }
        .diag-steps {
            display: flex;
            flex-wrap: wrap;
            gap: 1rem;
            margin: 1rem 0;
        }
        .diag-step {
            flex: 1;
            background: white;
            border-radius: 1rem;
            padding: 1rem;
            text-align: center;
            box-shadow: 0 2px 6px rgba(0,0,0,0.05);
        }
        .error-code-table {
            background: white;
            border-radius: 1.5rem;
            overflow: hidden;
            border: 1px solid #eef2ff;
            margin: 1.5rem 0;
        }
        .error-table-row {
            display: flex;
            border-bottom: 1px solid #eef2ff;
        }
        .error-table-row:last-child {
            border-bottom: none;
        }
        .error-code {
            width: 30%;
            background: #f8fafc;
            padding: 0.8rem 1rem;
            font-weight: 700;
            font-family: monospace;
        }
        .error-desc {
            width: 70%;
            padding: 0.8rem 1rem;
            color: #334155;
        }
        .alert-banner {
            background: #fff7ed;
            border-left: 5px solid #f59e0b;
            padding: 1rem 1.5rem;
            border-radius: 1rem;
            margin: 1rem 0;
        }
        @media (max-width: 768px) {
            .diag-steps {
                flex-direction: column;
            }
            .error-table-row {
                flex-direction: column;
            }
            .error-code, .error-desc {
                width: 100%;
            }
        }