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

    body {
        font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
        line-height: 1.6;
        color: #333;
        background-color: #fff;
    }

    .zt31tn-header {
        background: rgba(255, 255, 255, 0.95);
        backdrop-filter: blur(10px);
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        z-index: 1000;
        border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    }

    .zt31tn-nav {
        max-width: 1200px;
        margin: 0 auto;
        padding: 0 20px;
        display: flex;
        align-items: center;
        justify-content: space-between;
        height: 70px;
    }

    .zt31tn-logo img {
        height: 40px;
        width: auto;
    }

    .zt31tn-menu-toggle {
        display: none;
        flex-direction: column;
        background: none;
        border: none;
        cursor: pointer;
        padding: 5px;
    }

    .zt31tn-menu-toggle span {
        width: 25px;
        height: 3px;
        background: #333;
        margin: 3px 0;
        transition: 0.3s;
        border-radius: 2px;
    }

    .zt31tn-nav-menu {
        display: flex;
        list-style: none;
        gap: 30px;
        align-items: center;
    }

    .zt31tn-nav-menu a {
        text-decoration: none;
        color: #333;
        font-weight: 500;
        transition: color 0.3s;
        position: relative;
    }

    .zt31tn-nav-menu a:hover {
        color: #0088cc;
    }

    .zt31tn-nav-menu a.active {
        color: #0088cc;
    }

    .zt31tn-nav-menu a.active::after {
        content: '';
        position: absolute;
        bottom: -5px;
        left: 0;
        right: 0;
        height: 2px;
        background: #0088cc;
        border-radius: 1px;
    }

    .zt31tn-nav-overlay {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(0, 0, 0, 0.5);
        z-index: 999;
    }

    .zt31tn-tutorial-header {
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        color: white;
        padding: 120px 0 80px;
        text-align: center;
        position: relative;
        overflow: hidden;
    }

    .zt31tn-tutorial-header::before {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: url('images/feature.jpg') center/cover;
        opacity: 0.1;
        z-index: 1;
    }

    .zt31tn-tutorial-header .zt31tn-container {
        position: relative;
        z-index: 2;
    }

    .zt31tn-container {
        max-width: 1200px;
        margin: 0 auto;
        padding: 0 20px;
    }

    .zt31tn-tutorial-title {
        font-size: 3rem;
        font-weight: 700;
        margin-bottom: 20px;
        text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    }

    .zt31tn-tutorial-subtitle {
        font-size: 1.2rem;
        opacity: 0.9;
        max-width: 600px;
        margin: 0 auto;
        line-height: 1.8;
    }

    .zt31tn-breadcrumb {
        background: #f8f9fa;
        padding: 15px 0;
        border-bottom: 1px solid #e9ecef;
    }

    .zt31tn-breadcrumb-list {
        display: flex;
        align-items: center;
        gap: 10px;
        font-size: 0.9rem;
        color: #666;
    }

    .zt31tn-breadcrumb-list a {
        color: #0088cc;
        text-decoration: none;
    }

    .zt31tn-breadcrumb-list a:hover {
        text-decoration: underline;
    }

    .zt31tn-breadcrumb-separator {
        color: #999;
    }

    .zt31tn-tutorial-content {
        padding: 60px 0;
    }

    .zt31tn-tutorial-grid {
        display: grid;
        grid-template-columns: 250px 1fr;
        gap: 40px;
        align-items: start;
    }

    .zt31tn-tutorial-sidebar {
        position: sticky;
        top: 100px;
        background: #f8f9fa;
        border-radius: 12px;
        padding: 30px;
        border: 1px solid #e9ecef;
    }

    .zt31tn-sidebar-title {
        font-size: 1.1rem;
        font-weight: 600;
        margin-bottom: 20px;
        color: #333;
        display: flex;
        align-items: center;
        gap: 8px;
    }

    .zt31tn-sidebar-nav {
        list-style: none;
    }

    .zt31tn-sidebar-nav li {
        margin-bottom: 8px;
    }

    .zt31tn-sidebar-nav a {
        display: block;
        padding: 8px 12px;
        color: #666;
        text-decoration: none;
        border-radius: 6px;
        transition: all 0.3s;
        font-size: 0.9rem;
    }

    .zt31tn-sidebar-nav a:hover,
    .zt31tn-sidebar-nav a.active {
        background: #0088cc;
        color: white;
    }

    .zt31tn-tutorial-main {
        background: white;
        border-radius: 12px;
        padding: 40px;
        box-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
        border: 1px solid #e9ecef;
    }

    .zt31tn-section {
        margin-bottom: 50px;
    }

    .zt31tn-section:last-child {
        margin-bottom: 0;
    }

    .zt31tn-section-title {
        font-size: 1.8rem;
        font-weight: 600;
        margin-bottom: 25px;
        color: #333;
        display: flex;
        align-items: center;
        gap: 12px;
        padding-bottom: 15px;
        border-bottom: 2px solid #f0f0f0;
    }

    .zt31tn-section-icon {
        width: 40px;
        height: 40px;
        background: linear-gradient(135deg, #0088cc, #0066aa);
        border-radius: 10px;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 1.2rem;
        color: white;
    }

    .zt31tn-steps-grid {
        display: grid;
        gap: 25px;
    }

    .zt31tn-step-card {
        background: #f8f9fa;
        border-radius: 12px;
        padding: 25px;
        border-left: 4px solid #0088cc;
        transition: all 0.3s;
        position: relative;
    }

    .zt31tn-step-card:hover {
        transform: translateY(-2px);
        box-shadow: 0 8px 25px rgba(0, 136, 204, 0.15);
    }

    .zt31tn-step-header {
        display: flex;
        align-items: center;
        gap: 15px;
        margin-bottom: 15px;
    }

    .zt31tn-step-number {
        width: 35px;
        height: 35px;
        background: #0088cc;
        color: white;
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        font-weight: 600;
        font-size: 0.9rem;
    }

    .zt31tn-step-title {
        font-size: 1.2rem;
        font-weight: 600;
        color: #333;
    }

    .zt31tn-step-desc {
        color: #666;
        line-height: 1.7;
        margin-left: 50px;
    }

    .zt31tn-features-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
        gap: 25px;
        margin-top: 30px;
    }

    .zt31tn-feature-card {
        background: white;
        border: 1px solid #e9ecef;
        border-radius: 12px;
        padding: 25px;
        text-align: center;
        transition: all 0.3s;
    }

    .zt31tn-feature-card:hover {
        transform: translateY(-5px);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
        border-color: #0088cc;
    }

    .zt31tn-feature-icon {
        font-size: 2.5rem;
        margin-bottom: 15px;
        display: block;
    }

    .zt31tn-feature-title {
        font-size: 1.1rem;
        font-weight: 600;
        margin-bottom: 10px;
        color: #333;
    }

    .zt31tn-feature-desc {
        color: #666;
        font-size: 0.9rem;
        line-height: 1.6;
    }

    .zt31tn-tips-box {
        background: linear-gradient(135deg, #e3f2fd, #f3e5f5);
        border: 1px solid #bbdefb;
        border-radius: 12px;
        padding: 25px;
        margin: 30px 0;
        position: relative;
    }

    .zt31tn-tips-box::before {
        content: '💡';
        position: absolute;
        top: -10px;
        left: 20px;
        background: white;
        padding: 5px 10px;
        border-radius: 20px;
        font-size: 1.2rem;
    }

    .zt31tn-tips-title {
        font-weight: 600;
        color: #1976d2;
        margin-bottom: 10px;
        margin-left: 20px;
    }

    .zt31tn-tips-content {
        color: #333;
        line-height: 1.7;
    }

    .zt31tn-image-showcase {
        text-align: center;
        margin: 40px 0;
    }

    .zt31tn-showcase-img {
        max-width: 100%;
        height: auto;
        border-radius: 12px;
        box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
        border: 1px solid #e9ecef;
    }

    .zt31tn-showcase-caption {
        margin-top: 15px;
        color: #666;
        font-size: 0.9rem;
        font-style: italic;
    }

    .zt31tn-cta-section {
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        color: white;
        padding: 60px 0;
        text-align: center;
        margin-top: 60px;
        border-radius: 20px;
    }

    .zt31tn-cta-title {
        font-size: 2rem;
        font-weight: 600;
        margin-bottom: 15px;
    }

    .zt31tn-cta-desc {
        font-size: 1.1rem;
        opacity: 0.9;
        margin-bottom: 30px;
        max-width: 600px;
        margin-left: auto;
        margin-right: auto;
    }

    .zt31tn-cta-buttons {
        display: flex;
        gap: 20px;
        justify-content: center;
        flex-wrap: wrap;
    }

    .zt31tn-btn {
        display: inline-flex;
        align-items: center;
        gap: 8px;
        padding: 12px 30px;
        border-radius: 25px;
        text-decoration: none;
        font-weight: 600;
        transition: all 0.3s;
        border: 2px solid transparent;
    }

    .zt31tn-btn-primary {
        background: white;
        color: #667eea;
    }

    .zt31tn-btn-primary:hover {
        background: #f8f9fa;
        transform: translateY(-2px);
    }

    .zt31tn-btn-outline {
        background: transparent;
        color: white;
        border-color: white;
    }

    .zt31tn-btn-outline:hover {
        background: white;
        color: #667eea;
    }

    .zt31tn-footer {
        background: #2c3e50;
        color: white;
        padding: 50px 0 30px;
        margin-top: 80px;
    }

    .zt31tn-footer-content {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 40px;
        margin-bottom: 40px;
    }

    .zt31tn-footer-section h3 {
        font-size: 1.2rem;
        margin-bottom: 20px;
        color: #ecf0f1;
    }

    .zt31tn-footer-section ul {
        list-style: none;
    }

    .zt31tn-footer-section ul li {
        margin-bottom: 10px;
    }

    .zt31tn-footer-section ul li a {
        color: #bdc3c7;
        text-decoration: none;
        transition: color 0.3s;
    }

    .zt31tn-footer-section ul li a:hover {
        color: #3498db;
    }

    .zt31tn-footer-bottom {
        border-top: 1px solid #34495e;
        padding-top: 30px;
        text-align: center;
        color: #95a5a6;
    }

    @media (max-width: 768px) {
        .zt31tn-menu-toggle {
            display: flex;
        }

        .zt31tn-nav-menu {
            display: none;
            position: fixed;
            top: 70px;
            left: 0;
            right: 0;
            background: white;
            flex-direction: column;
            padding: 20px;
            box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
            gap: 15px;
        }

        .zt31tn-nav-menu.active {
            display: flex;
        }

        .zt31tn-nav-overlay.active {
            display: block;
        }

        .zt31tn-tutorial-title {
            font-size: 2rem;
        }

        .zt31tn-tutorial-grid {
            grid-template-columns: 1fr;
            gap: 30px;
        }

        .zt31tn-tutorial-sidebar {
            position: static;
            order: 2;
        }

        .zt31tn-tutorial-main {
            padding: 25px;
        }

        .zt31tn-section-title {
            font-size: 1.5rem;
        }

        .zt31tn-features-grid {
            grid-template-columns: 1fr;
        }

        .zt31tn-cta-buttons {
            flex-direction: column;
            align-items: center;
        }

        .zt31tn-footer-content {
            grid-template-columns: 1fr;
            gap: 30px;
        }
    }

    @media (max-width: 480px) {
        .zt31tn-container {
            padding: 0 15px;
        }

        .zt31tn-tutorial-header {
            padding: 100px 0 60px;
        }

        .zt31tn-tutorial-title {
            font-size: 1.8rem;
        }

        .zt31tn-tutorial-main {
            padding: 20px;
        }

        .zt31tn-step-desc {
            margin-left: 0;
            margin-top: 10px;
        }

        .zt31tn-step-header {
            flex-direction: column;
            align-items: flex-start;
            gap: 10px;
        }
    }