/* 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;
        --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;
    }

    /* 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: 720px; 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 */
    #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 Cards */
    #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; }

    /* Feature Cards */
    #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, #3b82f6, #0ea5e9); }
    #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);
    }

    /* Scenario Cards */
    #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; }
    }