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

    body {
        font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
        line-height: 1.6;
        color: #333;
        background-color: #f8f9fa;
    }

    .tfci-header {
        background: #25d366;
        box-shadow: 0 2px 10px rgba(37, 211, 102, 0.1);
        position: sticky;
        top: 0;
        z-index: 1000;
    }

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

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

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

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

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

    .tfci-nav-menu a {
        color: white;
        text-decoration: none;
        font-weight: 500;
        transition: opacity 0.3s;
        padding: 10px 0;
    }

    .tfci-nav-menu a:hover {
        opacity: 0.8;
    }

    .tfci-nav-overlay {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0, 0, 0, 0.5);
        z-index: 999;
    }

    .tfci-help-header {
        background: linear-gradient(135deg, #25d366 0%, #128c7e 100%);
        color: white;
        padding: 60px 0 80px;
        text-align: center;
        position: relative;
        overflow: hidden;
    }

    .tfci-help-header::before {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="20" cy="20" r="2" fill="rgba(255,255,255,0.1)"/><circle cx="80" cy="40" r="1.5" fill="rgba(255,255,255,0.1)"/><circle cx="40" cy="70" r="1" fill="rgba(255,255,255,0.1)"/><circle cx="70" cy="80" r="2.5" fill="rgba(255,255,255,0.1)"/></svg>');
        animation: tfci-float 20s infinite linear;
    }

    @keyframes tfci-float {
        0% { transform: translateY(0px); }
        100% { transform: translateY(-100px); }
    }

    .tfci-help-container {
        max-width: 1200px;
        margin: 0 auto;
        padding: 0 20px;
        position: relative;
        z-index: 2;
    }

    .tfci-help-title {
        font-size: 3rem;
        font-weight: 700;
        margin-bottom: 20px;
        text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    }

    .tfci-help-subtitle {
        font-size: 1.2rem;
        opacity: 0.9;
        margin-bottom: 40px;
        max-width: 600px;
        margin-left: auto;
        margin-right: auto;
    }

    .tfci-search-box {
        max-width: 600px;
        margin: 0 auto;
        position: relative;
    }

    .tfci-search-input {
        width: 100%;
        padding: 18px 60px 18px 20px;
        border: none;
        border-radius: 50px;
        font-size: 1.1rem;
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
        outline: none;
        transition: box-shadow 0.3s;
    }

    .tfci-search-input:focus {
        box-shadow: 0 6px 30px rgba(0, 0, 0, 0.15);
    }

    .tfci-search-btn {
        position: absolute;
        right: 15px;
        top: 50%;
        transform: translateY(-50%);
        background: #25d366;
        border: none;
        width: 40px;
        height: 40px;
        border-radius: 50%;
        color: white;
        cursor: pointer;
        display: flex;
        align-items: center;
        justify-content: center;
        transition: background 0.3s;
    }

    .tfci-search-btn:hover {
        background: #128c7e;
    }

    .tfci-main-content {
        max-width: 1200px;
        margin: -40px auto 0;
        padding: 0 20px;
        position: relative;
        z-index: 10;
    }

    .tfci-help-categories {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: 30px;
        margin-bottom: 80px;
    }

    .tfci-category-card {
        background: white;
        border-radius: 20px;
        padding: 40px 30px;
        text-align: center;
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
        transition: all 0.3s ease;
        cursor: pointer;
        border: 2px solid transparent;
    }

    .tfci-category-card:hover {
        transform: translateY(-10px);
        box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
        border-color: #25d366;
    }

    .tfci-category-icon {
        font-size: 3rem;
        margin-bottom: 20px;
        display: block;
    }

    .tfci-category-title {
        font-size: 1.4rem;
        font-weight: 600;
        color: #333;
        margin-bottom: 15px;
    }

    .tfci-category-desc {
        color: #666;
        line-height: 1.6;
    }

    .tfci-faq-section {
        background: white;
        border-radius: 20px;
        padding: 60px 40px;
        margin-bottom: 60px;
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    }

    .tfci-section-title {
        font-size: 2.5rem;
        font-weight: 700;
        text-align: center;
        margin-bottom: 50px;
        color: #333;
        position: relative;
    }

    .tfci-section-title::after {
        content: '';
        position: absolute;
        bottom: -15px;
        left: 50%;
        transform: translateX(-50%);
        width: 80px;
        height: 4px;
        background: linear-gradient(90deg, #25d366, #128c7e);
        border-radius: 2px;
    }

    .tfci-faq-list {
        max-width: 800px;
        margin: 0 auto;
    }

    .tfci-faq-item {
        border-bottom: 1px solid #eee;
        margin-bottom: 20px;
    }

    .tfci-faq-question {
        width: 100%;
        background: none;
        border: none;
        padding: 25px 0;
        text-align: left;
        font-size: 1.2rem;
        font-weight: 600;
        color: #333;
        cursor: pointer;
        display: flex;
        justify-content: space-between;
        align-items: center;
        transition: color 0.3s;
    }

    .tfci-faq-question:hover {
        color: #25d366;
    }

    .tfci-faq-toggle {
        font-size: 1.5rem;
        transition: transform 0.3s;
        color: #25d366;
    }

    .tfci-faq-item.active .tfci-faq-toggle {
        transform: rotate(45deg);
    }

    .tfci-faq-answer {
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease;
        padding: 0 0 0 0;
    }

    .tfci-faq-item.active .tfci-faq-answer {
        max-height: 500px;
        padding: 0 0 25px 0;
    }

    .tfci-faq-answer p {
        color: #666;
        line-height: 1.8;
        font-size: 1rem;
    }

    .tfci-install-guide {
        background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
        border-radius: 20px;
        padding: 60px 40px;
        margin-bottom: 60px;
    }

    .tfci-guide-steps {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 40px;
        max-width: 1000px;
        margin: 0 auto;
    }

    .tfci-step-card {
        background: white;
        border-radius: 15px;
        padding: 30px 25px;
        text-align: center;
        position: relative;
        box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
        transition: transform 0.3s;
    }

    .tfci-step-card:hover {
        transform: translateY(-5px);
    }

    .tfci-step-number {
        position: absolute;
        top: -15px;
        left: 50%;
        transform: translateX(-50%);
        width: 40px;
        height: 40px;
        background: #25d366;
        color: white;
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        font-weight: 700;
        font-size: 1.2rem;
    }

    .tfci-step-title {
        font-size: 1.3rem;
        font-weight: 600;
        margin: 20px 0 15px;
        color: #333;
    }

    .tfci-step-desc {
        color: #666;
        line-height: 1.6;
    }

    .tfci-contact-section {
        background: white;
        border-radius: 20px;
        padding: 60px 40px;
        text-align: center;
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    }

    .tfci-contact-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 40px;
        max-width: 800px;
        margin: 40px auto 0;
    }

    .tfci-contact-card {
        padding: 30px 20px;
        border-radius: 15px;
        background: #f8f9fa;
        transition: all 0.3s;
    }

    .tfci-contact-card:hover {
        background: #25d366;
        color: white;
        transform: translateY(-5px);
    }

    .tfci-contact-icon {
        font-size: 2.5rem;
        margin-bottom: 20px;
        display: block;
    }

    .tfci-contact-title {
        font-size: 1.2rem;
        font-weight: 600;
        margin-bottom: 10px;
    }

    .tfci-contact-desc {
        opacity: 0.8;
    }

    .tfci-footer {
        background: #1a1a1a;
        color: white;
        padding: 60px 0 30px;
        margin-top: 80px;
    }

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

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

    .tfci-footer-section h3 {
        font-size: 1.3rem;
        margin-bottom: 20px;
        color: #25d366;
    }

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

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

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

    .tfci-footer-section ul li a:hover {
        color: #25d366;
    }

    .tfci-footer-bottom {
        border-top: 1px solid #333;
        padding-top: 30px;
        text-align: center;
        color: #999;
    }

    .tfci-footer-brand {
        font-size: 1.5rem;
        font-weight: 700;
        color: #25d366;
        margin-bottom: 15px;
    }

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

        .tfci-nav-menu {
            display: none;
            position: fixed;
            top: 70px;
            left: 0;
            width: 100%;
            background: #25d366;
            flex-direction: column;
            padding: 20px;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
        }

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

        .tfci-help-title {
            font-size: 2.2rem;
        }

        .tfci-help-subtitle {
            font-size: 1rem;
        }

        .tfci-section-title {
            font-size: 2rem;
        }

        .tfci-faq-section,
        .tfci-install-guide,
        .tfci-contact-section {
            padding: 40px 20px;
        }

        .tfci-guide-steps {
            grid-template-columns: 1fr;
        }

        .tfci-help-categories {
            grid-template-columns: 1fr;
        }
    }

    @media (max-width: 480px) {
        .tfci-help-title {
            font-size: 1.8rem;
        }

        .tfci-search-input {
            font-size: 1rem;
            padding: 15px 50px 15px 15px;
        }

        .tfci-faq-question {
            font-size: 1.1rem;
            padding: 20px 0;
        }
    }