* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        body {
            font-family: 'Inter', sans-serif;
            background-color: #ffffff;
            color: #1e2a3e;
            line-height: 1.5;
            scroll-behavior: smooth;
        }
        /* color palette: neutral base + accent (blue #2c7da0 / orange #e67e22) */
        :root {
            --primary: #2c7da0;
            --primary-dark: #1f5e7a;
            --accent: #e67e22;
            --accent-light: #f0b27a;
            --gray-light: #f8fafc;
            --gray-mid: #e2e8f0;
            --text-dark: #0f172a;
            --text-muted: #475569;
            --white: #ffffff;
            --shadow-sm: 0 10px 25px -5px rgba(0,0,0,0.05), 0 8px 10px -6px rgba(0,0,0,0.02);
            --shadow-md: 0 20px 25px -5px rgba(0,0,0,0.08), 0 8px 10px -6px rgba(0,0,0,0.02);
            --transition: all 0.25s ease;
        }
        .container {
            max-width: 1280px;
            margin: 0 auto;
            padding: 0 24px;
        }
        section {
            padding: 80px 0;
        }
        .section-title {
            font-size: 2rem;
            font-weight: 700;
            text-align: center;
            margin-bottom: 48px;
            color: var(--text-dark);
            letter-spacing: -0.01em;
        }
        .section-title span {
            color: var(--primary);
            border-bottom: 3px solid var(--accent);
            padding-bottom: 8px;
        }
        /* Sticky Header */
        .header {
            position: sticky;
            top: 0;
            background: rgba(255,255,255,0.98);
            backdrop-filter: blur(2px);
            box-shadow: 0 1px 3px rgba(0,0,0,0.05);
            z-index: 1000;
            transition: var(--transition);
        }
        .nav-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 16px 24px;
            flex-wrap: wrap;
        }
        .logo {
            font-size: 1.6rem;
            font-weight: 800;
            color: var(--primary);
            letter-spacing: -0.5px;
        }
        .logo i {
            color: var(--accent);
            margin-right: 6px;
        }
        .nav-menu {
            display: flex;
            gap: 28px;
            list-style: none;
            align-items: center;
            flex-wrap: wrap;
        }
        .nav-menu a {
            text-decoration: none;
            font-weight: 500;
            color: var(--text-dark);
            transition: var(--transition);
        }
        .nav-menu a:hover {
            color: var(--primary);
        }
        .btn-primary {
            background: var(--primary);
            color: white;
            border: none;
            padding: 10px 24px;
            border-radius: 40px;
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition);
            display: inline-block;
            text-decoration: none;
        }
        .btn-primary:hover {
            background: var(--primary-dark);
            transform: translateY(-2px);
        }
        .btn-secondary {
            background: transparent;
            border: 2px solid var(--primary);
            color: var(--primary);
            padding: 8px 22px;
            border-radius: 40px;
            font-weight: 600;
            transition: var(--transition);
            cursor: pointer;
            display: inline-block;
            text-decoration: none;
        }
        .btn-secondary:hover {
            background: var(--primary);
            color: white;
        }
        .btn-accent {
            background: var(--accent);
            color: white;
            border: none;
            padding: 12px 32px;
            border-radius: 40px;
            font-weight: 600;
            transition: var(--transition);
            cursor: pointer;
        }
        .btn-accent:hover {
            background: #ce6a1f;
            transform: translateY(-2px);
        }
        /* Hero */
        .hero {
            background: linear-gradient(rgba(0,0,0,0.45), rgba(0,0,0,0.45)), url('../img/hero.avif');
            background-size: cover;
            background-position: center 30%;
            color: white;
            text-align: center;
            padding: 140px 0;
        }
        .hero h1 {
            font-size: 3.2rem;
            font-weight: 800;
            margin-bottom: 20px;
            letter-spacing: -0.02em;
        }
        .hero p {
            font-size: 1.25rem;
            max-width: 700px;
            margin: 0 auto 32px;
            opacity: 0.95;
        }
        .hero-buttons {
            display: flex;
            gap: 20px;
            justify-content: center;
            flex-wrap: wrap;
        }
        /* cards grid */
        .services-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: 32px;
        }
        .service-card {
            background: var(--white);
            border-radius: 24px;
            padding: 28px 20px;
            text-align: center;
            box-shadow: var(--shadow-sm);
            transition: var(--transition);
            border: 1px solid var(--gray-mid);
        }
        .service-card:hover {
            transform: translateY(-8px);
            box-shadow: var(--shadow-md);
            border-color: var(--primary);
        }
        .service-card i {
            font-size: 2.8rem;
            color: var(--primary);
            margin-bottom: 16px;
        }
        .service-card h3 {
            font-size: 1.35rem;
            margin-bottom: 12px;
        }
        .service-card p {
            color: var(--text-muted);
            font-size: 0.9rem;
        }
        /* Why Us */
        .why-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
            gap: 32px;
            text-align: center;
        }
        .why-item i {
            font-size: 2.2rem;
            background: #eef2ff;
            padding: 18px;
            border-radius: 60px;
            color: var(--primary);
            margin-bottom: 18px;
        }
        .why-item h4 {
            font-size: 1.3rem;
            margin-bottom: 8px;
        }
        /* stats */
        .about-stats {
            display: flex;
            gap: 40px;
            justify-content: center;
            margin-top: 32px;
            flex-wrap: wrap;
        }
        .stat {
            text-align: center;
            background: var(--gray-light);
            padding: 20px 28px;
            border-radius: 32px;
        }
        .stat-number {
            font-size: 2.2rem;
            font-weight: 800;
            color: var(--primary);
        }
        /* Testimonials */
        .testimonial-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 32px;
        }
        .testimonial-card {
            background: var(--gray-light);
            padding: 28px;
            border-radius: 28px;
            transition: var(--transition);
        }
        .testimonial-card:hover {
            background: white;
            box-shadow: var(--shadow-sm);
        }
        .stars {
            color: #f4b942;
            margin: 12px 0;
        }
        .testimonial-card img {
            width: 60px;
            height: 60px;
            border-radius: 50%;
            object-fit: cover;
            margin-bottom: 12px;
        }
        /* forms */
        .form-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 40px;
            background: var(--gray-light);
            padding: 40px;
            border-radius: 32px;
        }
        .contact-form, .newsletter-box {
            background: white;
            padding: 28px;
            border-radius: 28px;
            box-shadow: var(--shadow-sm);
        }
        input, select, textarea {
            width: 100%;
            padding: 12px 16px;
            margin: 8px 0 16px;
            border: 1px solid var(--gray-mid);
            border-radius: 28px;
            font-family: inherit;
            transition: 0.2s;
        }
        input:focus, select:focus, textarea:focus {
            outline: none;
            border-color: var(--primary);
            box-shadow: 0 0 0 2px rgba(44,125,160,0.2);
        }
        .form-message {
            margin-top: 12px;
            font-weight: 500;
            color: #2e7d32;
        }
        .error-msg {
            color: #d32f2f;
            font-size: 0.8rem;
            margin-top: -12px;
            margin-bottom: 12px;
        }
        /* warranty section */
        .warranty-content {
            background: linear-gradient(135deg, #f0f7fa 0%, #ffffff 100%);
            border-radius: 48px;
            padding: 48px;
            display: flex;
            flex-wrap: wrap;
            gap: 32px;
            justify-content: space-between;
            align-items: center;
        }
        .warranty-text {
            flex: 2;
        }
        .warranty-benefits {
            flex: 1;
            display: flex;
            flex-direction: column;
            gap: 16px;
        }
        /* footer */
        .footer {
            background: #0f172a;
            color: #cbd5e1;
            padding: 48px 0 24px;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 40px;
            margin-bottom: 40px;
        }
        .footer a {
            color: #cbd5e1;
            text-decoration: none;
        }
        .footer a:hover {
            color: var(--accent);
        }
        .social-icons i {
            font-size: 1.5rem;
            margin-right: 16px;
        }
        .copyright {
            text-align: center;
            padding-top: 32px;
            border-top: 1px solid #2d3a4e;
        }
        /* modal */
        .modal {
            display: none;
            position: fixed;
            top: 0; left: 0;
            width: 100%; height: 100%;
            background: rgba(0,0,0,0.7);
            justify-content: center;
            align-items: center;
            z-index: 2000;
        }
        .modal-content {
            background: white;
            max-width: 500px;
            width: 90%;
            padding: 32px;
            border-radius: 32px;
            position: relative;
            max-height: 80vh;
            overflow-y: auto;
        }
        .close-modal {
            position: absolute;
            right: 20px;
            top: 15px;
            font-size: 28px;
            cursor: pointer;
        }
        /* Sticky mobile CTA */
        .mobile-sticky-cta {
            display: none;
            position: fixed;
            bottom: 20px;
            right: 20px;
            background: var(--accent);
            color: white;
            padding: 14px 22px;
            border-radius: 50px;
            font-weight: bold;
            box-shadow: 0 8px 20px rgba(0,0,0,0.2);
            z-index: 1100;
            text-decoration: none;
            align-items: center;
            gap: 8px;
        }
        @media (max-width: 992px) {
            .nav-menu {
                gap: 16px;
            }
            .form-grid {
                grid-template-columns: 1fr;
            }
        }
        @media (max-width: 768px) {
            .nav-container {
                flex-direction: column;
                gap: 12px;
            }
            .nav-menu {
                justify-content: center;
            }
            .hero h1 {
                font-size: 2.2rem;
            }
            section {
                padding: 60px 0;
            }
            .mobile-sticky-cta {
                display: flex;
            }
            .warranty-content {
                flex-direction: column;
                text-align: center;
            }
        }
        button:active { transform: scale(0.97);}
        .legal-links {
            display: flex;
            gap: 24px;
            justify-content: center;
            margin: 20px 0;
        }
        .legal-links a {
            color: var(--primary);
            cursor: pointer;
            text-decoration: underline;
        }