:root {
            --red-primary: #ff0033;
            --red-dark: #cc0029;
            --red-light: #ff3355;
            --black: #0a0a0a;
            --black-light: #1a1a1a;
            --black-lighter: #2a2a2a;
            --gray-dark: #333333;
            --gray-medium: #555555;
            --gray-light: #888888;
            --white: #ffffff;
            --text-primary: #e0e0e0;
            --text-secondary: #b0b0b0;
            --border: #2a2a2a;
        }

        [data-theme="light"] {
            --black: #f5f5f5;
            --black-light: #ffffff;
            --black-lighter: #f0f0f0;
            --gray-dark: #e0e0e0;
            --gray-medium: #d0d0d0;
            --text-primary: #1a1a1a;
            --text-secondary: #666666;
            --border: #e0e0e0;
        }

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

        body {
            font-family: 'Arial', 'Helvetica', sans-serif;
            background: var(--black);
            color: var(--text-primary);
            line-height: 1.6;
            transition: background-color 0.3s ease, color 0.3s ease;
        }

        a {
            text-decoration: none;
            color: inherit;
        }

        /* Header */
        .tube-header {
            background: var(--black-light);
            border-bottom: 3px solid var(--red-primary);
            position: sticky;
            top: 0;
            z-index: 1000;
            box-shadow: 0 2px 10px rgba(0,0,0,0.3);
            transition: background-color 0.3s ease;
        }

        .header-top {
            background: var(--black);
            padding: 8px 0;
            border-bottom: 1px solid var(--border);
            transition: background-color 0.3s ease;
        }

        .header-top-inner {
            max-width: 1400px;
            margin: 0 auto;
            padding: 0 20px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 12px;
            color: var(--text-secondary);
        }

        .top-links {
            display: flex;
            gap: 20px;
        }

        .top-link {
            color: var(--text-secondary);
            transition: color 0.3s;
        }

        .top-link:hover {
            color: var(--red-primary);
        }

        .top-stats {
            display: flex;
            gap: 16px;
            align-items: center;
        }

        .top-stat {
            display: flex;
            align-items: center;
            gap: 6px;
        }

        .top-stat i {
            color: var(--red-primary);
        }

        /* Theme Toggle */
        .theme-toggle {
            background: var(--black-lighter);
            border: 1px solid var(--border);
            border-radius: 20px;
            width: 50px;
            height: 26px;
            position: relative;
            cursor: pointer;
            transition: all 0.3s;
        }

        .theme-toggle-slider {
            position: absolute;
            top: 2px;
            left: 2px;
            width: 20px;
            height: 20px;
            background: var(--red-primary);
            border-radius: 50%;
            transition: transform 0.3s;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 10px;
            color: white;
        }

        [data-theme="light"] .theme-toggle-slider {
            transform: translateX(24px);
        }

        /* Mobile Theme Toggle */
        .mobile-theme-toggle {
            display: none;
        }

        /* Main Header */
        .header-main {
            max-width: 1400px;
            margin: 0 auto;
            padding: 12px 20px;
            display: flex;
            align-items: center;
            gap: 24px;
        }

        .logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 28px;
            font-weight: 900;
            color: var(--text-primary);
        }

        .logo-icon {
            width: 42px;
            height: 42px;
            background: var(--red-primary);
            border-radius: 6px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 22px;
            color: white;
        }

        .logo-text {
            letter-spacing: -1px;
        }

        .logo-text span {
            color: var(--red-primary);
        }

        /* Search */
        .search-container {
            flex: 1;
            max-width: 600px;
        }

        .search-wrapper {
            display: flex;
            background: var(--black-lighter);
            border: 2px solid var(--border);
            border-radius: 4px;
            overflow: hidden;
            transition: all 0.3s;
        }

        .search-wrapper:focus-within {
            border-color: var(--red-primary);
        }

        .search-input {
            flex: 1;
            background: transparent;
            border: none;
            padding: 10px 16px;
            color: var(--text-primary);
            font-size: 14px;
            outline: none;
        }

        .search-input::placeholder {
            color: var(--text-secondary);
        }

        .search-btn {
            background: var(--red-primary);
            color: white;
            border: none;
            padding: 10px 24px;
            font-weight: 700;
            cursor: pointer;
            transition: background 0.3s;
        }

        .search-btn:hover {
            background: var(--red-dark);
        }

        /* Header Actions */
        .header-actions {
            display: flex;
            gap: 12px;
        }

        .header-btn {
            background: var(--black-lighter);
            border: 1px solid var(--border);
            color: var(--text-primary);
            padding: 8px 16px;
            border-radius: 4px;
            font-size: 13px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s;
            display: flex;
            align-items: center;
            gap: 6px;
        }

        .header-btn:hover {
            background: var(--red-primary);
            border-color: var(--red-primary);
            color: white;
        }

        .header-btn i {
            font-size: 14px;
        }

        /* Navigation */
        .tube-nav {
            background: var(--black-light);
            border-bottom: 1px solid var(--border);
            transition: background-color 0.3s ease;
        }

        .nav-inner {
            max-width: 1400px;
            margin: 0 auto;
            padding: 0 20px;
            display: flex;
            gap: 4px;
            overflow-x: auto;
            scrollbar-width: none;
        }

        .nav-inner::-webkit-scrollbar {
            display: none;
        }

        .nav-item {
            padding: 12px 18px;
            color: var(--text-secondary);
            font-size: 13px;
            font-weight: 600;
            white-space: nowrap;
            cursor: pointer;
            transition: all 0.3s;
            border-bottom: 3px solid transparent;
        }

        .nav-item:hover {
            color: var(--text-primary);
            background: var(--black-lighter);
        }

        .nav-item.active {
            color: var(--red-primary);
            border-bottom-color: var(--red-primary);
        }

        /* Container */
        .container {
            max-width: 1400px;
            margin: 0 auto;
            padding: 20px;
        }

        .tube-layout {
            display: grid;
            grid-template-columns: 220px 1fr;
            gap: 20px;
        }

        /* Sidebar */
        .sidebar {
            display: flex;
            flex-direction: column;
            gap: 20px;
        }

        .sidebar-section {
            background: var(--black-light);
            border-radius: 4px;
            padding: 16px;
            border: 1px solid var(--border);
            transition: background-color 0.3s ease;
        }

        .sidebar-title {
            font-size: 14px;
            font-weight: 700;
            color: var(--text-primary);
            margin-bottom: 12px;
            text-transform: uppercase;
            letter-spacing: 0.5px;
        }

        .sidebar-list {
            display: flex;
            flex-direction: column;
            gap: 4px;
        }

        .sidebar-link {
            padding: 8px 12px;
            color: var(--text-secondary);
            font-size: 13px;
            border-radius: 3px;
            cursor: pointer;
            transition: all 0.3s;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .sidebar-link:hover {
            background: var(--black-lighter);
            color: var(--text-primary);
        }

        .sidebar-link.active {
            background: var(--red-primary);
            color: white;
        }

        .sidebar-link i {
            width: 16px;
            text-align: center;
        }

        /* Main Content */
        .main-content {
            background: var(--black-light);
            border-radius: 6px;
            padding: 32px;
            border: 1px solid var(--border);
            transition: background-color 0.3s ease;
        }

        .content-header {
            margin-bottom: 32px;
            padding-bottom: 20px;
            border-bottom: 2px solid var(--border);
        }

        .content-title {
            font-size: 32px;
            font-weight: 900;
            color: var(--text-primary);
            margin-bottom: 8px;
        }

        .content-subtitle {
            font-size: 16px;
            color: var(--text-secondary);
        }

        .content-body h2 {
            font-size: 24px;
            font-weight: 700;
            color: var(--text-primary);
            margin-top: 32px;
            margin-bottom: 16px;
        }

        .content-body h3 {
            font-size: 18px;
            font-weight: 700;
            color: var(--text-primary);
            margin-top: 24px;
            margin-bottom: 12px;
        }

        .content-body p {
            margin-bottom: 16px;
            color: var(--text-secondary);
            line-height: 1.8;
        }

        .content-body ul, 
        .content-body ol {
            margin-bottom: 16px;
            margin-left: 24px;
            color: var(--text-secondary);
        }

        .content-body li {
            margin-bottom: 8px;
            line-height: 1.8;
        }

        .content-body strong {
            color: var(--text-primary);
            font-weight: 700;
        }

        .content-body a {
            color: var(--red-primary);
            text-decoration: underline;
        }

        .content-body a:hover {
            color: var(--red-light);
        }

        .info-box {
            background: var(--black-lighter);
            border-left: 4px solid var(--red-primary);
            padding: 16px 20px;
            margin: 24px 0;
            border-radius: 4px;
        }

        .info-box-title {
            font-size: 16px;
            font-weight: 700;
            color: var(--text-primary);
            margin-bottom: 8px;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .info-box-title i {
            color: var(--red-primary);
        }

        .info-box p {
            margin-bottom: 0;
        }

        .contact-form {
            display: flex;
            flex-direction: column;
            gap: 16px;
            margin-top: 24px;
        }

        .form-group {
            display: flex;
            flex-direction: column;
            gap: 8px;
        }

        .form-label {
            font-size: 14px;
            font-weight: 600;
            color: var(--text-primary);
        }

        .form-input,
        .form-textarea {
            background: var(--black-lighter);
            border: 1px solid var(--border);
            border-radius: 4px;
            padding: 12px 16px;
            color: var(--text-primary);
            font-size: 14px;
            font-family: inherit;
            outline: none;
            transition: all 0.3s;
        }

        .form-input:focus,
        .form-textarea:focus {
            border-color: var(--red-primary);
        }

        .form-textarea {
            min-height: 150px;
            resize: vertical;
        }

        .form-submit {
            background: var(--red-primary);
            color: white;
            border: none;
            border-radius: 4px;
            padding: 12px 24px;
            font-size: 16px;
            font-weight: 700;
            cursor: pointer;
            transition: all 0.3s;
            align-self: flex-start;
        }

        .form-submit:hover {
            background: var(--red-dark);
            transform: translateY(-2px);
        }

        .premium-features {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 20px;
            margin-top: 24px;
        }

        .feature-card {
            background: var(--black-lighter);
            border: 1px solid var(--border);
            border-radius: 6px;
            padding: 20px;
            transition: all 0.3s;
        }

        .feature-card:hover {
            border-color: var(--red-primary);
            transform: translateY(-4px);
        }

        .feature-icon {
            width: 48px;
            height: 48px;
            background: var(--red-primary);
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 16px;
            font-size: 24px;
            color: white;
        }

        .feature-title {
            font-size: 18px;
            font-weight: 700;
            color: var(--text-primary);
            margin-bottom: 8px;
        }

        .feature-description {
            color: var(--text-secondary);
            font-size: 14px;
            line-height: 1.6;
        }

        /* Footer */
        .tube-footer {
            background: var(--black-light);
            border-top: 1px solid var(--border);
            margin-top: 40px;
            padding: 24px 20px;
            transition: background-color 0.3s ease;
        }

        .footer-inner {
            max-width: 1400px;
            margin: 0 auto;
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 12px;
            color: var(--text-secondary);
        }

        .footer-links {
            display: flex;
            gap: 20px;
        }

        .footer-link {
            transition: color 0.3s;
        }

        .footer-link:hover {
            color: var(--red-primary);
        }

        .footer-link.active {
            color: var(--red-primary);
            font-weight: 700;
        }

        /* Cookie Banner */
        .cookie-banner {
            position: fixed;
            bottom: 0;
            left: 0;
            right: 0;
            background: var(--black-light);
            border-top: 2px solid var(--red-primary);
            padding: 16px 20px;
            z-index: 2000;
            box-shadow: 0 -2px 10px rgba(0,0,0,0.5);
            transition: background-color 0.3s ease;
        }

        .cookie-inner {
            max-width: 1400px;
            margin: 0 auto;
            display: flex;
            justify-content: space-between;
            align-items: center;
            gap: 20px;
        }

        .cookie-text {
            flex: 1;
            font-size: 13px;
            color: var(--text-secondary);
        }

        .cookie-actions {
            display: flex;
            gap: 10px;
        }

        .cookie-btn {
            padding: 8px 20px;
            border-radius: 3px;
            border: none;
            font-weight: 700;
            font-size: 13px;
            cursor: pointer;
            transition: all 0.3s;
        }

        .btn-accept {
            background: var(--red-primary);
            color: white;
        }

        .btn-accept:hover {
            background: var(--red-dark);
        }

        .btn-decline {
            background: var(--black-lighter);
            color: var(--text-primary);
            border: 1px solid var(--border);
        }

        .btn-decline:hover {
            background: var(--gray-dark);
        }

        /* Responsive */
        @media (max-width: 1024px) {
            .tube-layout {
                grid-template-columns: 1fr;
            }

            .sidebar {
                display: none;
            }
        }

        @media (max-width: 768px) {
            .header-top {
                display: none;
            }

            .header-main {
                flex-wrap: wrap;
                padding: 10px 15px;
                gap: 12px;
                justify-content: space-between;
            }

            .logo {
                font-size: 22px;
                flex: 0 0 auto;
            }

            .logo-icon {
                width: 36px;
                height: 36px;
                font-size: 18px;
            }

            .mobile-theme-toggle {
                display: block;
                flex: 0 0 auto;
            }

            .search-container {
                order: 3;
                flex: 1 1 100%;
                max-width: 100%;
            }

            .header-actions {
                display: none;
            }

            .main-content {
                padding: 20px;
            }

            .content-title {
                font-size: 24px;
            }

            .content-body h2 {
                font-size: 20px;
            }

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

            .cookie-inner {
                flex-direction: column;
                text-align: center;
            }

            .footer-inner {
                flex-direction: column;
                gap: 16px;
                text-align: center;
            }

            .footer-links {
                display: grid;
                grid-template-columns: repeat(2, 1fr);
                gap: 10px 20px;
                width: 100%;
                max-width: 300px;
            }

            .container {
                padding: 15px;
            }
        }

        @media (max-width: 480px) {
            .footer-links {
                grid-template-columns: repeat(3, 1fr);
                gap: 8px 12px;
                font-size: 11px;
            }
        }