:root {
            --tobacco: #ebdcb9;
            --mahogany: #2b1c11;
            --text-primary: #2b1c11;
            --glass-bg: rgba(43, 28, 17, 0.05);
            --light-bg: rgba(43, 28, 17, 0.08);
            --transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
            --bg-color: #ebdcb9;
        }

        html {
            scroll-behavior: smooth;
            -webkit-overflow-scrolling: touch;
        }

        ::selection {
            background: rgba(43, 28, 17, 0.35);
            color: #f5ecd8;
        }
        input::selection,
        textarea::selection {
            background: rgba(43, 28, 17, 0.35);
            color: #f5ecd8;
        }

        body {
            margin: 0;
            font-family: 'Inter', system-ui, -apple-system, sans-serif;
            color: var(--text-primary);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
            background-color: #ebdcb9;
            position: relative;
        }

        /* ── Декоративная графика: каждый рисунок — отдельный маленький SVG,
           закреплённый через position:fixed с простым отступом в px от края
           экрана (как кнопки RU/EN). Никакого масштабирования по viewBox —
           поэтому расположение абсолютно одинаковое на любом устройстве,
           независимо от соотношения сторон экрана. ── */
        .deco {
            position: fixed;
            z-index: 0;
            pointer-events: none;
            user-select: none;
        }
        .deco-sun { top: 100px; right: 40px; width: 140px; height: 140px; }
        .deco-stevark { top: 92px; left: 20px; width: 28px; height: auto; }
        .deco-earth { top: 427px; left: 20px; width: 60px; height: 60px; }
        .deco-tree { left: 16px; bottom: 16px; width: 90px; height: auto; }
        .deco-building { right: 16px; bottom: 16px; width: 110px; height: auto; }
        /* Одни и те же значения на всех устройствах и разрешениях —
           без брейкпоинтов, чтобы расположение не "гуляло" между устройствами. */
        .sk-line { stroke: #2b1c11; stroke-width: 1.3; fill: none; stroke-linecap: round; stroke-linejoin: round; }
        .sk-thin { stroke: #2b1c11; stroke-width: 0.6; fill: none; opacity: 0.4; }
        .sk-axis { stroke: #2b1c11; stroke-width: 0.4; stroke-dasharray: 6,4; opacity: 0.15; }
        .sk-earth { stroke: #2b1c11; stroke-width: 0.9; fill: none; opacity: 0.65; stroke-linecap: round; }
        .sk-accent { stroke: #c8542a; stroke-width: 1.3; fill: none; stroke-linecap: round; stroke-linejoin: round; }

        /* ── Текст просто лежит на фоне, без подложки: декоративные .deco-*
           элементы стоят на месте (position:fixed), а текст в обычном потоке
           страницы едет вместе со скроллом. Никакого стекла/затемнения —
           единая картина по всему сайту, как в шапке. Читаемость держится на
           мягкой текстовой тени (halo), а не на плашке. ── */
        .sr-only {
            position: absolute;
            width: 1px; height: 1px;
            padding: 0; margin: -1px;
            overflow: hidden;
            clip: rect(0,0,0,0);
            white-space: nowrap;
            border: 0;
        }

        .glass-content {
            position: relative;
            z-index: 2;
            text-shadow: 0 1px 4px rgba(235, 220, 185, 0.9);
        }
        header .brand-group {
            padding: 20px 24px 8px;
            max-width: 640px;
            margin: 0 auto;
        }

        /* ── Рукописные формулы — декоративные, разбросаны по секциям ── */
        .formula-scribble {
            position: absolute;
            font-family: 'Caveat', cursive;
            font-weight: 700;
            color: var(--mahogany);
            opacity: 0.34;
            pointer-events: none;
            user-select: none;
            z-index: 1;
            line-height: 1;
            white-space: nowrap;
        }
        .formula-1 { top: 90px; left: 5%; font-size: clamp(22px, 3vw, 32px); transform: rotate(-7deg); }
        .formula-2 { bottom: 6%; left: 3%; font-size: clamp(20px, 2.6vw, 29px); transform: rotate(5deg); }
        .formula-3 { top: 10%; right: 3%; font-size: clamp(20px, 2.6vw, 28px); transform: rotate(-4deg); }
        .formula-4 { bottom: 8%; right: 4%; font-size: clamp(22px, 3vw, 30px); transform: rotate(6deg); }
        .formula-5 { top: 40px; left: 3%; font-size: clamp(20px, 2.6vw, 28px); transform: rotate(-5deg); }
        .formula-6 { top: 8%; left: 4%; font-size: clamp(20px, 2.6vw, 28px); transform: rotate(4deg); }
        .formula-7 { bottom: 4%; right: 4%; font-size: clamp(20px, 2.6vw, 28px); transform: rotate(-6deg); }
        .formula-8 { bottom: 16%; right: 7%; font-size: clamp(19px, 2.4vw, 26px); transform: rotate(10deg); }
        .formula-9 { top: 18%; left: 6%; font-size: clamp(19px, 2.4vw, 26px); transform: rotate(-9deg); }
        .formula-10 { bottom: 14%; left: 6%; font-size: clamp(19px, 2.4vw, 26px); transform: rotate(7deg); }
        .formula-11 { top: 14%; right: 7%; font-size: clamp(19px, 2.4vw, 26px); transform: rotate(-5deg); }
        .formula-12 { bottom: 12%; left: 7%; font-size: clamp(19px, 2.4vw, 26px); transform: rotate(9deg); }
        .formula-13 { bottom: 30px; left: 5%; font-size: clamp(19px, 2.6vw, 27px); transform: rotate(8deg); }
        .formula-14 { top: 12%; left: 5%; font-size: clamp(19px, 2.4vw, 26px); transform: rotate(-8deg); }
        .formula-15 { top: 40px; right: 6%; font-size: clamp(18px, 2.2vw, 24px); transform: rotate(6deg); }
        @media (max-width: 640px) {
            .formula-scribble { opacity: 0.26; }
            .formula-3, .formula-4, .formula-7, .formula-9, .formula-11, .formula-15 { display: none; } /* на мобильном оставляем меньше, чтобы не мешали тексту */
        }

        /* ── Штампы "380V" — как инженерная печать на кальке ── */
        .volt-stamp {
            position: absolute;
            display: flex;
            align-items: center;
            justify-content: center;
            text-align: center;
            aspect-ratio: 1;
            width: clamp(140px, 20vw, 240px);
            border: 3px solid var(--mahogany);
            border-radius: 50%;
            font-family: 'Inter', sans-serif;
            font-weight: 800;
            font-size: clamp(20px, 2.4vw, 30px);
            letter-spacing: 3px;
            color: var(--mahogany);
            opacity: 0.09;
            pointer-events: none;
            user-select: none;
            z-index: 1;
        }
        .volt-stamp-1 { top: 20px; left: 4%; transform: rotate(-11deg); }
        .volt-stamp-2 { bottom: 30px; left: 4%; transform: rotate(9deg); }
        @media (max-width: 640px) {
            .volt-stamp { opacity: 0.07; }
        }

        footer { position: relative; overflow: hidden; border-top: 1px solid rgba(43, 28, 17, 0.15); }
        footer > * { position: relative; z-index: 1; }

        /* Контент должен быть выше декоративных слоёв */
        header, main, footer, .lang-switcher, .nav-toggle, .mobile-nav {
            position: relative;
            z-index: 2;
        }

        /* ── Переключатель языков ── */
        .lang-switcher {
            position: fixed;
            top: 20px;
            left: 20px;
            z-index: 1002;
            display: flex;
            gap: 8px;
        }
        .lang-btn {
            background: rgba(43, 28, 17, 0.22);
            backdrop-filter: blur(16px) saturate(160%);
            -webkit-backdrop-filter: blur(16px) saturate(160%);
            border: 1px solid rgba(43, 28, 17, 0.35);
            padding: 8px 12px;
            border-radius: 8px;
            cursor: pointer;
            font-family: 'Inter', sans-serif;
            font-size: 13px;
            font-weight: 600;
            text-transform: uppercase;
            letter-spacing: 1px;
            color: var(--mahogany);
            transition: var(--transition);
            box-shadow: 0 4px 16px rgba(20, 12, 5, 0.25), inset 0 1px 0 rgba(255, 244, 214, 0.15);
        }
        .lang-btn:hover {
            background: rgba(43, 28, 17, 0.4);
            color: var(--mahogany);
        }

        /* ── Гамбургер (всегда виден, двигается со скроллом) ── */
        .nav-toggle {
            display: block;
            position: fixed;
            top: 20px;
            right: 20px;
            z-index: 1001;
            background: rgba(43, 28, 17, 0.22);
            backdrop-filter: blur(16px) saturate(160%);
            -webkit-backdrop-filter: blur(16px) saturate(160%);
            border: 1px solid rgba(43, 28, 17, 0.35);
            padding: 10px;
            border-radius: 10px;
            cursor: pointer;
            box-shadow:
                0 4px 16px rgba(20, 12, 5, 0.25),
                inset 0 1px 0 rgba(255, 244, 214, 0.15);
            transition: var(--transition);
        }
        .nav-toggle span {
            display: block;
            width: 25px;
            height: 2px;
            background: var(--mahogany);
            margin: 5px 0;
            transition: var(--transition);
            transform-origin: center;
        }
        .nav-toggle.active span:nth-child(1) {
            transform: translateY(7px) rotate(45deg);
        }
        .nav-toggle.active span:nth-child(2) {
            opacity: 0;
            transform: translateX(-10px);
        }
        .nav-toggle.active span:nth-child(3) {
            transform: translateY(-7px) rotate(-45deg);
        }

        /* ── Liquid Glass меню ── */
        .mobile-nav {
            position: fixed;
            top: 16px;
            right: 16px;
            width: 280px;
            background: rgba(43, 28, 17, 0.5);
            backdrop-filter: blur(28px) saturate(180%);
            -webkit-backdrop-filter: blur(28px) saturate(180%);
            border: 1px solid rgba(43, 28, 17, 0.4);
            border-radius: 20px;
            z-index: 999;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            gap: 0;
            padding: 56px 24px 24px;
            transform-origin: calc(100% - 27px) 27px;
            transform: scale(0.6);
            opacity: 0;
            visibility: hidden;
            pointer-events: none;
            will-change: transform, opacity;
            transition:
                transform 0.3s cubic-bezier(0.4, 0, 0.2, 1),
                opacity 0.28s ease,
                visibility 0s linear 0.3s;
            box-shadow:
                0 8px 40px rgba(20, 12, 5, 0.3),
                0 2px 8px rgba(20, 12, 5, 0.15),
                inset 0 1px 0 rgba(255, 244, 214, 0.12),
                inset 0 -1px 0 rgba(20, 12, 5, 0.15);
        }
        .mobile-nav.active {
            transform: scale(1);
            opacity: 1;
            visibility: visible;
            pointer-events: auto;
            transition:
                transform 0.3s cubic-bezier(0.16, 1, 0.3, 1),
                opacity 0.2s ease,
                visibility 0s linear 0s;
        }
        .mobile-nav a {
            font-size: 15px;
            color: #f0e4ce;
            text-decoration: none;
            text-transform: uppercase;
            font-weight: 500;
            letter-spacing: 2px;
            transition: opacity 0.3s ease;
            width: 100%;
            text-align: center;
            padding: 12px 0;
            border-bottom: 1px solid rgba(255, 244, 214, 0.15);
        }
        .mobile-nav a:last-child { border-bottom: none; }
        .mobile-nav a:hover { opacity: 0.6; }
        .mobile-nav .contact-link {
            color: #f0e4ce !important;
            font-size: 15px;
            font-weight: 500;
            text-transform: uppercase;
            letter-spacing: 2px;
            margin: 0;
        }

        /* ── Шапка ── */
        header {
            min-height: 100vh;
            min-height: 100dvh;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 90px 20px 60px;
            text-align: center;
            border-bottom: 1px solid rgba(43, 28, 17, 0.15);
            box-sizing: border-box;
        }

        .subtitle {
            font-size: 18px;
            color: var(--mahogany);
            margin: 15px 0 25px;
            letter-spacing: 2px;
            text-transform: lowercase;
            text-shadow: 0 1px 4px rgba(235, 220, 185, 0.9);
        }
        .subtitle-accent {
            color: #c8542a;
        }
        .subtitle-concept {
            font-size: 14px;
            line-height: 1.5;
            color: var(--mahogany);
            max-width: 480px;
            margin: 0 auto 20px;
            opacity: 0.85;
            text-shadow: 0 1px 4px rgba(235, 220, 185, 0.9);
        }

        .hero-chips {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            gap: 10px;
            max-width: 480px;
            margin: 0 auto 8px;
        }
        .hero-chip {
            flex: 0 1 auto;
            padding: 8px 18px;
            background: rgba(43, 28, 17, 0.14);
            backdrop-filter: blur(12px) saturate(160%);
            -webkit-backdrop-filter: blur(12px) saturate(160%);
            border: 1px solid rgba(43, 28, 17, 0.28);
            border-radius: 20px;
            color: var(--mahogany) !important;
            text-decoration: none;
            font-size: 12px;
            font-weight: 600;
            text-transform: uppercase;
            letter-spacing: 1.2px;
            transition: var(--transition);
        }
        .hero-chip:hover {
            background: rgba(43, 28, 17, 0.28);
        }
        @media (max-width: 480px) {
            .hero-chip { font-size: 11px; padding: 7px 14px; }
        }

        .hero-illustration {
            display: block;
            width: 220px;
            height: auto;
            margin: 4px auto 8px;
            opacity: 0.85;
        }
        @media (max-width: 480px) {
            .hero-illustration { width: 170px; }
        }

        /* ── Акценты под кнопками в шапке ── */
        .header-accents {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            gap: 0;
            margin-top: 32px;
            padding: 14px 0;
        }
        .header-accent-item {
            display: flex;
            align-items: center;
            gap: 8px;
            padding: 6px 22px;
            font-size: 12px;
            font-weight: 600;
            text-transform: uppercase;
            letter-spacing: 1.8px;
            color: var(--mahogany);
            border-right: 1px solid rgba(43, 28, 17, 0.2);
        }
        .header-accent-item:last-child { border-right: none; }
        .header-accent-item svg {
            flex-shrink: 0;
            opacity: 0.75;
        }
        @media (max-width: 640px) {
            .header-accent-item {
                width: 50%;
                border-right: none;
                border-bottom: 1px solid rgba(43, 28, 17, 0.12);
                justify-content: center;
                padding: 10px 12px;
                font-size: 11px;
            }
            .header-accent-item:nth-child(odd) {
                border-right: 1px solid rgba(43, 28, 17, 0.12);
            }
            .header-accent-item:nth-last-child(-n+2) {
                border-bottom: none;
            }
        }

        /* ── Секции ── */
        .section {
            position: relative;
            max-width: 1100px;
            margin: 0 auto;
            padding: 90px 20px;
        }
        @media (max-width: 640px) {
            .section { padding: 60px 20px; }
        }

        h2 {
            font-size: 24px;
            font-weight: 400;
            margin-bottom: 60px;
            text-align: center;
            text-transform: uppercase;
            letter-spacing: 4px;
            position: relative;
            color: var(--mahogany);
        }
        h2::after {
            content: '';
            position: absolute;
            bottom: -15px;
            left: 50%;
            transform: translateX(-50%);
            width: 40px;
            height: 2px;
            background: var(--mahogany);
        }

        .adv-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 50px;
        }
        .adv-item h3 {
            color: var(--mahogany);
            text-transform: uppercase;
            font-size: 16px;
            font-weight: 400;
            margin-bottom: 20px;
            letter-spacing: 2.5px;
        }

        /* Блок "О подходе" */
        #about .adv-item {
            max-width: 800px;
            margin: 0 auto;
            background: transparent;
            padding: 40px;
            border-radius: 4px;
            border-left: 2px solid var(--mahogany);
            color: var(--mahogany);
        }
        #about .adv-item p {
            font-size: 19px;
            font-weight: 300;
            line-height: 1.8;
            margin-bottom: 25px;
        }
        #about .adv-item p:last-child { margin-bottom: 0; }

        /* ── Этапы работы ── */
        #steps {
            border-top: 1px solid rgba(43, 28, 17, 0.15);
            border-bottom: 1px solid rgba(43, 28, 17, 0.15);
        }
        .steps-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 0;
        }
        .step-item {
            display: flex;
            flex-direction: column;
            align-items: center;
            text-align: center;
            padding: 0 24px;
            border-right: 1px solid rgba(43, 28, 17, 0.15);
        }
        .step-item:last-child { border-right: none; }
        .step-accent {
            font-size: 22px;
            color: var(--mahogany);
            opacity: 0.45;
            margin-bottom: 16px;
            line-height: 1;
        }
        .step-title {
            font-size: 13px;
            font-weight: 500;
            text-transform: uppercase;
            letter-spacing: 2.5px;
            color: var(--mahogany);
            margin-bottom: 10px;
        }
        .step-desc {
            font-size: 14px;
            font-weight: 300;
            color: var(--mahogany);
            opacity: 0.75;
            line-height: 1.6;
        }
        @media (max-width: 768px) {
            .steps-grid {
                grid-template-columns: repeat(2, 1fr);
                gap: 40px 0;
            }
            .step-item {
                border-right: none;
                border-bottom: 1px solid rgba(43, 28, 17, 0.12);
                padding-bottom: 36px;
            }
            .step-item:nth-child(odd) { border-right: 1px solid rgba(43, 28, 17, 0.12); }
            .step-item:nth-last-child(-n+2) { border-bottom: none; }
        }
        @media (max-width: 480px) {
            .steps-grid { grid-template-columns: 1fr; gap: 0; }
            .step-item { border-right: none !important; border-bottom: 1px solid rgba(43, 28, 17, 0.12); padding: 28px 0; }
            .step-item:last-child { border-bottom: none; }
        }

        /* ── Портфолио ── */
        .portfolio-category {
            margin-bottom: 30px;
            border: 1px solid var(--mahogany);
            border-radius: 4px;
            overflow: hidden;
            background: var(--glass-bg);
        }

        .category-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            width: 100%;
            padding: 18px 24px;
            background: transparent;
            border: none;
            cursor: pointer;
            transition: background 0.3s ease;
        }
        .category-header:hover { background: rgba(255, 255, 255, 0.08); }

        .category-title {
            font-family: 'Inter', sans-serif;
            font-size: 16px;
            font-weight: 500;
            color: var(--mahogany);
            text-transform: uppercase;
            letter-spacing: 2.5px;
            text-align: left;
        }

        .category-arrow {
            font-size: 18px;
            color: var(--mahogany);
            transition: transform 0.3s ease;
            flex-shrink: 0;
        }
        .category-header[aria-expanded="true"] .category-arrow {
            transform: rotate(180deg);
        }

        .category-content {
            display: grid;
            grid-template-rows: 0fr;
            padding: 0 20px;
            overflow: hidden;
            transition: grid-template-rows 0.35s cubic-bezier(0.4, 0, 0.2, 1),
                        padding 0.35s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .category-content.open {
            grid-template-rows: 1fr;
            padding: 20px;
        }

        .mosaic {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            grid-auto-rows: 240px;
            gap: 15px;
            min-height: 0;
        }
        .mosaic-item {
            position: relative;
            display: block;
            cursor: zoom-in;
            overflow: hidden;
        }
        .mosaic-item img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            filter: grayscale(100%) brightness(0.7);
            transition: var(--transition);
            -webkit-user-drag: none;
            user-select: none;
            pointer-events: none;
        }
        .mosaic-item:hover img {
            filter: grayscale(0%) brightness(1);
            transform: scale(1.02);
        }
        .big { grid-column: span 2; grid-row: span 2; }
        .medium { grid-column: span 2; }

        /* ── Футер ── */
        footer {
            background: transparent;
            padding: 100px 20px;
            text-align: center;
        }

        .footer-caption {
            color: var(--mahogany);
            font-size: 14px;
            margin-bottom: 12px;
            letter-spacing: 1px;
        }

        .footer-contacts {
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 8px;
            margin-bottom: 40px;
        }

        .contact-link {
            color: var(--mahogany) !important;
            text-decoration: none;
            font-size: 22px;
            font-weight: 300;
            display: block;
            margin: 10px 0;
            letter-spacing: 1px;
            transition: var(--transition);
        }
        .contact-link:hover { opacity: 0.7; }

        .footer-consent {
            max-width: 420px;
            margin: 0 auto 24px;
            font-size: 12px;
            font-weight: 300;
            color: var(--mahogany);
            opacity: 0.85;
            line-height: 1.6;
        }
        .footer-consent a {
            color: var(--mahogany);
            text-decoration: underline;
        }
        .consent-check-wrap {
            cursor: pointer;
            -webkit-tap-highlight-color: transparent;
            -webkit-touch-callout: none;
        }
        .consent-check-wrap input[type="checkbox"] {
            -webkit-appearance: none;
            appearance: none;
            width: 15px;
            height: 15px;
            margin: 0 4px 0 0;
            vertical-align: -2px;
            background: rgba(235, 220, 185, 0.6);
            border: 1px solid rgba(43, 28, 17, 0.35);
            border-radius: 3px;
            cursor: pointer;
            position: relative;
            transition: background 0.25s ease, border-color 0.25s ease;
            outline: none;
        }
        .consent-check-wrap input[type="checkbox"]:hover {
            background: rgba(235, 220, 185, 0.9);
            border-color: var(--mahogany);
        }
        .consent-check-wrap input[type="checkbox"]:checked {
            background: var(--mahogany);
            border-color: var(--mahogany);
        }
        .consent-check-wrap input[type="checkbox"]:checked::after {
            content: '✓';
            position: absolute;
            color: #f0e4ce;
            font-size: 11px;
            font-weight: 900;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
        }
        .consent-warning {
            display: none;
            max-width: 420px;
            margin: -14px auto 24px;
            padding: 10px 16px;
            border: 1px solid rgba(180, 50, 50, 0.4);
            border-radius: 4px;
            background: rgba(180, 50, 50, 0.08);
            color: #8b2a2a;
            font-size: 12px;
            font-weight: 400;
        }
        .consent-warning.visible { display: block; }

        a[href^="tel"], a[href^="mailto"] {
            text-decoration: none;
        }

        .copyright {
            margin-top: 60px;
            color: #2b1c11;
            font-size: 13px;
            letter-spacing: 3px;
        }
        .copyright span { font-size: 13px; }

        /* Убираем синюю подсветку при клике */
        a, button, [role="button"] {
            -webkit-tap-highlight-color: transparent;
            -webkit-touch-callout: none;
        }
        a:focus:not(:focus-visible),
        button:focus:not(:focus-visible) { outline: none; }
        a:focus-visible,
        button:focus-visible {
            outline: 2px solid var(--mahogany);
            outline-offset: 2px;
        }

        img {
            pointer-events: none;
            user-select: none;
            -webkit-user-select: none;
            -webkit-user-drag: none;
        }

        @media (max-width: 768px) {
            .mosaic { grid-template-columns: repeat(2, 1fr); grid-auto-rows: 180px; }
            .big { grid-column: span 2; }
            header { padding: 80px 20px 50px; }
        }
        @media (max-width: 480px) {
            .mosaic { grid-template-columns: 1fr; grid-auto-rows: 200px; }
            .big, .medium { grid-column: span 1; }
        }