* { box-sizing: border-box; margin: 0; padding: 0; }
        html { scroll-behavior: smooth; }

        body { 
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
            background-color: #f8fafc;
            color: #334155;
            line-height: 1.8;
        }

        ::selection { background: #e0eeff; color: #0064E0; }

        .container-final {
            max-width: 1440px;
            margin: 0 auto;
            padding: 40px 20px;
            display: flex;
            gap: 24px;
            align-items: flex-start;
        }

        .card-style {
            background: #ffffff;
            border: 1px solid #e2e8f0;
            border-radius: 12px;
            box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
        }

        .sidebar-toc {
            width: 260px;
            flex-shrink: 0;
            padding: 24px;
        }

        .sidebar-toc .toc-title {
            font-weight: 600; 
            margin-bottom: 15px; 
            color: #1e293b; 
            border-left: 4px solid #0064E0; 
            padding-left: 10px;
        }

        .sidebar-toc ul { list-style: none; }
        .sidebar-toc li { margin-bottom: 12px; }
        .sidebar-toc a {
            text-decoration: none;
            color: #64748b;
            font-size: 14px;
            transition: all 0.3s ease;
        }
        .sidebar-toc a:hover {
            color: #0064E0;
            transform: translateX(8px);
            font-weight: 600;
        }

        .content-area {
            flex: 1;
            min-width: 0;
            padding: 50px 60px;
        }

        .abstract-gradient {
            background: linear-gradient(135deg, #f0f7ff 0%, #e0eeff 50%, #f0f7ff 100%);
            border: 1px solid rgba(0, 100, 220, 0.1);
            padding: 24px;
            border-radius: 10px;
            margin-bottom: 35px;
        }

        .abstract-gradient strong { 
            color: #0064E0; 
            display: block; 
            margin-bottom: 8px; 
            font-size: 20px;
            font-weight: 700;
        }

        .post-body section {
            padding: 18px 28px;
            margin: 15px -28px; 
            border-radius: 8px;
            transition: all 0.3s ease;
        }

        .post-body section:hover {
            background-color: rgba(0, 100, 224, 0.04); 
            box-shadow: inset 4px 0 0 #0064E0; 
            color: #0f172a; 
        }

        .post-body h1 {
            font-size: 32px;
            color: #1e293b;
            margin-bottom: 30px;
            line-height: 1.3;
            font-weight: 700;
        }

        .post-body h2 { 
            font-size: 24px; 
            margin: 35px 0 20px 0; 
            color: #1e293b; 
            font-weight: 600;
            padding-bottom: 8px;
            border-bottom: 2px solid #e0eeff;
        }

        .post-body h3 {
            font-size: 20px;
            margin: 20px 0 15px 0;
            color: #0064E0;
            font-weight: 600;
        }

        .post-body p {
            margin-bottom: 18px;
            font-size: 16px;
        }

        .post-body ul {
            margin: 15px 0 25px 30px;
        }

        .post-body li {
            margin-bottom: 12px;
            font-size: 16px;
        }

        .post-body strong {
            color: #0064E0;
            font-weight: 700;
        }

        .ship-step {
            background: #f1f5f9;
            border-left: 4px solid #0064E0;
            padding: 18px 22px;
            border-radius: 0 8px 8px 0;
            margin: 20px 0;
        }

        .cta-button {
            display: inline-block;
            background: #0064E0;
            color: white;
            padding: 15px 30px;
            border-radius: 8px;
            text-decoration: none;
            font-weight: 600;
            font-size: 18px;
            margin: 20px 0 30px 0;
            transition: all 0.3s ease;
            box-shadow: 0 4px 12px rgba(0, 100, 224, 0.2);
        }

        .cta-button:hover {
            background: #0050b8;
            transform: translateY(-3px);
            box-shadow: 0 6px 18px rgba(0, 100, 224, 0.3);
        }

        @media (max-width: 992px) {
            .container-final {
                flex-direction: column;
                padding: 10px 10px;
            }
            .sidebar-toc {
                width: 100%;
                margin-bottom: 15px;
            }
            .content-area {
                padding: 30px 25px;
            }
            .post-body h1 { font-size: 26px; }
            .post-body h2 { font-size: 22px; }
            .post-body section {
                margin: 5px 0; 
                padding: 12px 15px;
            }
        }