/* Original tool presentation, scoped to this detail page. */

        #yk-portal-v2 .yk-legacy-tool {
            --primary: #0369a1;
            --primary-light: #0ea5e9;
            --primary-dark: #075985;
            --accent: #10b981;
            --accent-light: #34d399;
            --bg-light: #f0f9ff;
            --bg-section: #f8fafc;
            --text-dark: #0f172a;
            --text-body: #334155;
            --text-muted: #64748b;
            --border-color: #e2e8f0;
            --nav-bg-color: rgba(13, 25, 49, 0.85);
            --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
            --shadow-md: 0 4px 16px rgba(0,0,0,0.1);
            --shadow-lg: 0 10px 30px rgba(0,0,0,0.12);
            --radius: 12px;
        }

        #yk-portal-v2 .yk-legacy-tool * { box-sizing: border-box; }

        #yk-portal-v2 .yk-legacy-tool {
            padding-top: 60px;
            font-family: 'Nunito', 'PingFang SC', 'Microsoft YaHei', sans-serif;
            color: var(--text-body);
            line-height: 1.7;
            background: #fff;
        }

        /* ===== Navbar ===== */
        #yk-portal-v2 .yk-legacy-tool .navbar {
            background-color: var(--nav-bg-color);
            backdrop-filter: blur(15px);
            -webkit-backdrop-filter: blur(15px);
            padding: 10px 0;
            transition: all 0.4s ease;
            box-shadow: 0 5px 20px rgba(0,0,0,0.1);
        }
        #yk-portal-v2 .yk-legacy-tool .navbar-scrolled { padding: 8px 0; background-color: rgba(13,25,49,0.95); box-shadow: 0 5px 20px rgba(0,0,0,0.2); }
        #yk-portal-v2 .yk-legacy-tool .navbar-brand { display: flex; align-items: center; padding: 0; }
        #yk-portal-v2 .yk-legacy-tool .navbar-brand img { height: 40px; transition: all 0.3s ease; margin-right: 10px; }
        #yk-portal-v2 .yk-legacy-tool .navbar-scrolled .navbar-brand img { height: 36px; }
        #yk-portal-v2 .yk-legacy-tool .brand-text { color: rgba(255,255,255,0.95); font-weight: 700; font-size: 1.5rem; transition: all 0.3s ease; text-shadow: 0 2px 10px rgba(0,0,0,0.2); }
        #yk-portal-v2 .yk-legacy-tool .navbar-scrolled .brand-text { font-size: 1.3rem; }
        #yk-portal-v2 .yk-legacy-tool .nav-item { position: relative; margin: 0 5px; }
        #yk-portal-v2 .yk-legacy-tool .nav-link { font-weight: 600; position: relative; padding: 10px 0 !important; margin: 0 15px; text-transform: uppercase; font-size: 14px; letter-spacing: 1px; transition: all 0.3s ease; color: rgba(255,255,255,0.9) !important; }
        #yk-portal-v2 .yk-legacy-tool .nav-link:before { content: ""; position: absolute; width: 5px; height: 5px; border-radius: 50%; bottom: 0; left: 50%; background-color: var(--primary-light); transform: translateX(-50%) scale(0); transition: transform 0.3s ease; }
        #yk-portal-v2 .yk-legacy-tool .nav-link:hover:before,#yk-portal-v2 .yk-legacy-tool  .nav-item.active .nav-link:before { transform: translateX(-50%) scale(1); }
        #yk-portal-v2 .yk-legacy-tool .nav-item.active .nav-link { color: var(--primary-light) !important; }
        #yk-portal-v2 .yk-legacy-tool .nav-item:hover .nav-link { color: #fff !important; transform: translateY(-3px); }
        #yk-portal-v2 .yk-legacy-tool .navbar-dark .navbar-toggler { border: none; outline: none; padding: 0; }
        #yk-portal-v2 .yk-legacy-tool .navbar-dark .navbar-toggler-icon { background-image: none; position: relative; width: 24px; height: 17px; }
        #yk-portal-v2 .yk-legacy-tool .navbar-dark .navbar-toggler-icon:before,#yk-portal-v2 .yk-legacy-tool  .navbar-dark .navbar-toggler-icon:after,#yk-portal-v2 .yk-legacy-tool  .navbar-dark .navbar-toggler-icon span { width: 100%; height: 2px; background-color: #fff; border-radius: 3px; position: absolute; left: 0; transition: all .3s ease; }
        #yk-portal-v2 .yk-legacy-tool .navbar-dark .navbar-toggler-icon:before,#yk-portal-v2 .yk-legacy-tool  .navbar-dark .navbar-toggler-icon:after { content: ''; }
        #yk-portal-v2 .yk-legacy-tool .navbar-dark .navbar-toggler-icon:before { top: 0; }
        #yk-portal-v2 .yk-legacy-tool .navbar-dark .navbar-toggler-icon span { top: 50%; transform: translateY(-50%); }
        #yk-portal-v2 .yk-legacy-tool .navbar-dark .navbar-toggler-icon:after { bottom: 0; }
        #yk-portal-v2 .yk-legacy-tool .navbar-dark .navbar-toggler[aria-expanded="true"] .navbar-toggler-icon:before { transform: translateY(7px) rotate(45deg); }
        #yk-portal-v2 .yk-legacy-tool .navbar-dark .navbar-toggler[aria-expanded="true"] .navbar-toggler-icon:after { transform: translateY(-7px) rotate(-45deg); }
        #yk-portal-v2 .yk-legacy-tool .navbar-dark .navbar-toggler[aria-expanded="true"] .navbar-toggler-icon span { opacity: 0; }
        @media (max-width: 991px) {
            #yk-portal-v2 .yk-legacy-tool .navbar-collapse { background-color: rgba(13,25,49,0.98); padding: 20px; border-radius: 10px; margin-top: 15px; box-shadow: 0 10px 30px rgba(0,0,0,0.15); }
            #yk-portal-v2 .yk-legacy-tool .navbar-nav .nav-item { margin: 5px 0; }
            #yk-portal-v2 .yk-legacy-tool .navbar-brand img { height: 36px; }
            #yk-portal-v2 .yk-legacy-tool .brand-text { font-size: 1.3rem; }
        }
        @media (max-width: 575px) {
            #yk-portal-v2 .yk-legacy-tool .navbar-brand img { height: 32px; }
            #yk-portal-v2 .yk-legacy-tool .brand-text { font-size: 1.2rem; }
        }

        /* ===== Hero ===== */
        #yk-portal-v2 .yk-legacy-tool .hero {
            background: linear-gradient(135deg, #075985 0%, #0369a1 40%, #0ea5e9 100%);
            padding: 5rem 0 4rem;
            text-align: center;
            color: #fff;
            position: relative;
            overflow: hidden;
            height: auto !important;
            min-height: auto !important;
        }
        #yk-portal-v2 .yk-legacy-tool .hero::before {
            content: '';
            position: absolute;
            top: 0; left: 0; width: 100%; height: 100%;
            background: radial-gradient(circle at 30% 50%, rgba(255,255,255,0.08) 0%, transparent 50%),
                        radial-gradient(circle at 70% 80%, rgba(255,255,255,0.05) 0%, transparent 40%);
            pointer-events: none;
        }
        #yk-portal-v2 .yk-legacy-tool .hero .container { position: relative; z-index: 1; }
        #yk-portal-v2 .yk-legacy-tool .hero h1 { font-size: 2.6rem; font-weight: 800; margin-bottom: 1rem; letter-spacing: 1px; }
        #yk-portal-v2 .yk-legacy-tool .hero .subtitle { font-size: 1.1rem; max-width: 700px; margin: 0 auto; opacity: 0.92; line-height: 1.8; }
        #yk-portal-v2 .yk-legacy-tool .hero .badge-row { margin-top: 1.5rem; display: flex; justify-content: center; gap: 12px; flex-wrap: wrap; }
        #yk-portal-v2 .yk-legacy-tool .hero .badge-item { background: rgba(255,255,255,0.18); backdrop-filter: blur(6px); padding: 6px 18px; border-radius: 20px; font-size: 0.85rem; font-weight: 600; }

        /* ===== Section Common ===== */
        #yk-portal-v2 .yk-legacy-tool .section { padding: 4rem 0; }
        #yk-portal-v2 .yk-legacy-tool .section-alt { background: var(--bg-section); }
        #yk-portal-v2 .yk-legacy-tool .section-title { text-align: center; margin-bottom: 3rem; }
        #yk-portal-v2 .yk-legacy-tool .section-title h2 { font-size: 2rem; font-weight: 700; color: var(--text-dark); margin-bottom: 0.5rem; }
        #yk-portal-v2 .yk-legacy-tool .section-title h2:after { display: none; }
        #yk-portal-v2 .yk-legacy-tool .section-title .underline { width: 50px; height: 4px; background: linear-gradient(90deg, var(--primary), var(--accent)); border-radius: 2px; margin: 0 auto; }
        #yk-portal-v2 .yk-legacy-tool .section-title p { color: var(--text-muted); margin-top: 0.8rem; font-size: 1rem; }

        /* ===== Pain Points ===== */
        #yk-portal-v2 .yk-legacy-tool .pain-card {
            background: #fff; border-radius: var(--radius); padding: 2rem;
            box-shadow: var(--shadow-sm); border: 1px solid var(--border-color);
            height: 100%; transition: transform 0.3s, box-shadow 0.3s;
        }
        #yk-portal-v2 .yk-legacy-tool .pain-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
        #yk-portal-v2 .yk-legacy-tool .pain-icon {
            width: 56px; height: 56px; border-radius: 14px;
            display: flex; align-items: center; justify-content: center;
            font-size: 1.4rem; color: #fff; margin-bottom: 1.2rem;
        }
        #yk-portal-v2 .yk-legacy-tool .pain-icon.red { background: linear-gradient(135deg, #ef4444, #f97316); }
        #yk-portal-v2 .yk-legacy-tool .pain-icon.amber { background: linear-gradient(135deg, #f59e0b, #eab308); }
        #yk-portal-v2 .yk-legacy-tool .pain-icon.blue { background: linear-gradient(135deg, var(--primary), var(--primary-light)); }
        #yk-portal-v2 .yk-legacy-tool .pain-card h5 { font-weight: 700; color: var(--text-dark); margin-bottom: 0.6rem; }
        #yk-portal-v2 .yk-legacy-tool .pain-card p { color: var(--text-muted); font-size: 0.95rem; margin: 0; }

        /* ===== Features ===== */
        #yk-portal-v2 .yk-legacy-tool .feature-card {
            background: #fff; border-radius: var(--radius); padding: 2rem 1.8rem;
            box-shadow: var(--shadow-sm); border: 1px solid var(--border-color);
            height: 100%; transition: transform 0.3s, box-shadow 0.3s;
        }
        #yk-portal-v2 .yk-legacy-tool .feature-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-md); }
        #yk-portal-v2 .yk-legacy-tool .feature-card .icon-wrap {
            width: 52px; height: 52px; border-radius: 12px;
            display: flex; align-items: center; justify-content: center;
            font-size: 1.3rem; color: #fff; margin-bottom: 1rem;
        }
        #yk-portal-v2 .yk-legacy-tool .feature-card h5 { font-weight: 700; color: var(--text-dark); font-size: 1.05rem; margin-bottom: 0.5rem; }
        #yk-portal-v2 .yk-legacy-tool .feature-card p { color: var(--text-muted); font-size: 0.92rem; margin: 0; line-height: 1.65; }
        #yk-portal-v2 .yk-legacy-tool .grad-1 { background: linear-gradient(135deg, var(--primary), var(--primary-light)); }
        #yk-portal-v2 .yk-legacy-tool .grad-2 { background: linear-gradient(135deg, var(--accent), #06b6d4); }
        #yk-portal-v2 .yk-legacy-tool .grad-3 { background: linear-gradient(135deg, #f59e0b, #f97316); }
        #yk-portal-v2 .yk-legacy-tool .grad-4 { background: linear-gradient(135deg, #ec4899, #f43f5e); }
        #yk-portal-v2 .yk-legacy-tool .grad-5 { background: linear-gradient(135deg, #6366f1, #3b82f6); }
        #yk-portal-v2 .yk-legacy-tool .grad-6 { background: linear-gradient(135deg, #14b8a6, #10b981); }

        /* ===== Screenshot ===== */
        #yk-portal-v2 .yk-legacy-tool .screenshot-wrapper { text-align: center; padding: 2rem 0; }
        #yk-portal-v2 .yk-legacy-tool .screenshot-wrapper img {
            max-width: 100%; height: auto; border-radius: var(--radius);
            box-shadow: var(--shadow-lg); border: 1px solid var(--border-color);
        }

        /* ===== Scenarios ===== */
        #yk-portal-v2 .yk-legacy-tool .scenario-card {
            background: #fff; border-radius: var(--radius); padding: 2rem;
            text-align: center; box-shadow: var(--shadow-sm); border: 1px solid var(--border-color);
            height: 100%; transition: transform 0.3s, box-shadow 0.3s;
        }
        #yk-portal-v2 .yk-legacy-tool .scenario-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
        #yk-portal-v2 .yk-legacy-tool .scenario-card .sc-icon {
            width: 64px; height: 64px; border-radius: 50%;
            display: flex; align-items: center; justify-content: center;
            margin: 0 auto 1.2rem; font-size: 1.5rem; color: #fff;
        }
        #yk-portal-v2 .yk-legacy-tool .scenario-card h5 { font-weight: 700; color: var(--text-dark); margin-bottom: 0.5rem; }
        #yk-portal-v2 .yk-legacy-tool .scenario-card p { color: var(--text-muted); font-size: 0.92rem; margin: 0; }

        /* ===== Steps ===== */
        #yk-portal-v2 .yk-legacy-tool .step-item {
            display: flex; align-items: flex-start; margin-bottom: 1.8rem;
            padding: 1.2rem 1.5rem; background: #fff; border-radius: var(--radius);
            box-shadow: var(--shadow-sm); border: 1px solid var(--border-color);
            transition: transform 0.3s;
        }
        #yk-portal-v2 .yk-legacy-tool .step-item:hover { transform: translateX(6px); }
        #yk-portal-v2 .yk-legacy-tool .step-num {
            width: 40px; height: 40px; border-radius: 50%;
            background: linear-gradient(135deg, var(--primary), var(--primary-light));
            color: #fff; display: flex; align-items: center; justify-content: center;
            font-weight: 700; font-size: 1rem; flex-shrink: 0; margin-right: 1.2rem;
        }
        #yk-portal-v2 .yk-legacy-tool .step-content h6 { font-weight: 700; color: var(--text-dark); margin-bottom: 0.3rem; }
        #yk-portal-v2 .yk-legacy-tool .step-content p { color: var(--text-muted); font-size: 0.93rem; margin: 0; }

        /* ===== FAQ ===== */
        #yk-portal-v2 .yk-legacy-tool .faq-item {
            background: #fff; border-radius: var(--radius); margin-bottom: 1rem;
            box-shadow: var(--shadow-sm); border: 1px solid var(--border-color); overflow: hidden;
        }
        #yk-portal-v2 .yk-legacy-tool .faq-question {
            padding: 1.1rem 1.5rem; cursor: pointer; display: flex;
            align-items: center; justify-content: space-between;
            font-weight: 600; color: var(--text-dark); transition: background 0.2s; user-select: none;
        }
        #yk-portal-v2 .yk-legacy-tool .faq-question:hover { background: var(--bg-light); }
        #yk-portal-v2 .yk-legacy-tool .faq-question i { transition: transform 0.3s; color: var(--primary); }
        #yk-portal-v2 .yk-legacy-tool .faq-question.active i { transform: rotate(180deg); }
        #yk-portal-v2 .yk-legacy-tool .faq-answer {
            max-height: 0; overflow: hidden; transition: max-height 0.35s ease, padding 0.35s ease;
            padding: 0 1.5rem; color: var(--text-muted); line-height: 1.75; font-size: 0.95rem;
        }
        #yk-portal-v2 .yk-legacy-tool .faq-answer.open { max-height: 500px; padding: 0 1.5rem 1.2rem; }

        /* ===== Download ===== */
        #yk-portal-v2 .yk-legacy-tool .download-section {
            background: linear-gradient(135deg, #075985, #0ea5e9);
            padding: 4rem 0; text-align: center; color: #fff;
        }
        #yk-portal-v2 .yk-legacy-tool .download-section h2 { font-size: 2rem; font-weight: 700; margin-bottom: 0.8rem; }
        #yk-portal-v2 .yk-legacy-tool .download-section p { opacity: 0.9; margin-bottom: 2rem; font-size: 1.05rem; }
        #yk-portal-v2 .yk-legacy-tool .btn-download {
            display: inline-block; background: #fff; color: var(--primary-dark);
            font-weight: 700; font-size: 1.1rem; padding: 14px 40px; border-radius: 50px;
            text-decoration: none; transition: all 0.3s; box-shadow: 0 4px 15px rgba(0,0,0,0.15);
        }
        #yk-portal-v2 .yk-legacy-tool .btn-download:hover {
            transform: translateY(-3px); box-shadow: 0 8px 25px rgba(0,0,0,0.2);
            color: var(--primary); text-decoration: none;
        }
        #yk-portal-v2 .yk-legacy-tool .btn-download i { margin-right: 8px; }
        #yk-portal-v2 .yk-legacy-tool .download-note { margin-top: 1rem; font-size: 0.88rem; opacity: 0.8; }

        /* ===== Responsive ===== */
        @media (max-width: 768px) {
            #yk-portal-v2 .yk-legacy-tool .hero { padding: 3.5rem 0 3rem; }
            #yk-portal-v2 .yk-legacy-tool .hero h1 { font-size: 2rem; }
            #yk-portal-v2 .yk-legacy-tool .section { padding: 3rem 0; }
            #yk-portal-v2 .yk-legacy-tool .section-title h2 { font-size: 1.6rem; }
            #yk-portal-v2 .yk-legacy-tool .step-item { padding: 1rem; }
        }
        @media (max-width: 576px) {
            #yk-portal-v2 .yk-legacy-tool .hero h1 { font-size: 1.5rem; }
            #yk-portal-v2 .yk-legacy-tool .hero .subtitle { font-size: 0.95rem; }
        }