/* ===== Reset & Variables ===== */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #1b1b1b;
    --primary-light: #2a2a2a;
    --accent: #c8451b;
    --accent-hover: #a83815;
    --accent-light: rgba(200,69,27,0.08);
    --text: #1b1b1b;
    --text-light: #6b6b6b;
    --text-muted: #999;
    --bg: #ffffff;
    --bg-alt: #f5f4f0;
    --bg-dark: #111111;
    --border: #e5e2dc;
    --radius: 4px;
    --radius-sm: 3px;
    --shadow: 0 1px 3px rgba(0,0,0,0.06);
    --shadow-lg: 0 8px 30px rgba(0,0,0,0.08);
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

img {
    max-width: 100%;
    display: block;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== Header ===== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0);
    backdrop-filter: blur(0px);
    transition: background 0.4s ease, backdrop-filter 0.4s ease, border-color 0.4s ease;
    border-bottom: 1px solid transparent;
}

.header.scrolled {
    background: rgba(255,255,255,0.97);
    backdrop-filter: blur(12px);
    border-bottom-color: var(--border);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: baseline;
    gap: 2px;
    font-size: 1.2rem;
    font-weight: 800;
    letter-spacing: -0.02em;
}

.logo-vt {
    color: var(--accent);
}

.header.scrolled .logo-vt {
    color: var(--accent);
}

.logo-steel {
    color: #fff;
    transition: color 0.4s ease;
}

.header.scrolled .logo-steel {
    color: var(--primary);
}

.logo-construction {
    color: rgba(255,255,255,0.5);
    font-weight: 400;
    font-size: 0.85em;
    margin-left: 2px;
    transition: color 0.4s ease;
}

.header.scrolled .logo-construction {
    color: var(--text-light);
}

.nav {
    display: flex;
    gap: 36px;
}

.nav-link {
    font-size: 0.85rem;
    font-weight: 500;
    color: rgba(255,255,255,0.85);
    transition: var(--transition);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.header.scrolled .nav-link {
    color: var(--text-light);
}

.nav-link:hover {
    color: #fff;
}

.header.scrolled .nav-link:hover {
    color: var(--text);
}

.nav-link.active {
    color: #fff;
}

.header.scrolled .nav-link.active {
    color: var(--accent);
}

/* Header actions */
.header-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

.whatsapp-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border-radius: 50%;
    color: #25d366;
    transition: var(--transition);
}

.whatsapp-btn svg {
    width: 20px;
    height: 20px;
}

.whatsapp-btn:hover {
    background: rgba(37,211,102,0.1);
}

.lang-toggle {
    display: flex;
    align-items: center;
    gap: 4px;
    background: none;
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: var(--radius);
    padding: 6px 12px;
    cursor: pointer;
    font-family: inherit;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.06em;
    transition: var(--transition);
}

.header.scrolled .lang-toggle {
    border-color: var(--border);
}

.lang-label {
    color: rgba(255,255,255,0.4);
    transition: var(--transition);
}

.lang-label.active {
    color: #fff;
}

.header.scrolled .lang-label {
    color: var(--text-muted);
}

.header.scrolled .lang-label.active {
    color: var(--text);
}

.lang-divider {
    color: rgba(255,255,255,0.15);
    font-weight: 300;
}

.header.scrolled .lang-divider {
    color: var(--border);
}

.lang-toggle:hover {
    border-color: rgba(255,255,255,0.4);
}

.header.scrolled .lang-toggle:hover {
    border-color: var(--text-muted);
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: #fff;
    transition: var(--transition);
    border-radius: 2px;
}

.header.scrolled .menu-toggle span {
    background: var(--text);
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ===== Hero ===== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    background: var(--bg-dark);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.hero-bg img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center 40%;
}

.hero::before {
    content: '';
    position: absolute;
    inset: 0;
    z-index: 1;
    background:
        linear-gradient(135deg, rgba(17,17,17,0.92) 0%, rgba(17,17,17,0.7) 50%, rgba(17,17,17,0.5) 100%);
}

.hero-overlay {
    display: none;
}

.hero-content {
    position: relative;
    z-index: 2;
    padding-top: 160px;
    padding-bottom: 120px;
    max-width: 800px;
}

.hero-title {
    font-size: clamp(3rem, 6vw, 5rem);
    font-weight: 800;
    color: #fff;
    line-height: 1.05;
    margin-bottom: 28px;
    letter-spacing: -0.04em;
}

.hero-title span {
    display: block;
    color: var(--accent);
}

.hero-subtitle {
    font-size: clamp(1rem, 1.8vw, 1.2rem);
    color: rgba(255,255,255,0.75);
    max-width: 520px;
    margin-bottom: 48px;
    line-height: 1.7;
    font-weight: 400;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    align-items: center;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 16px 40px;
    border-radius: var(--radius);
    font-size: 0.9rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.btn-primary {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
}

.btn-primary:hover {
    background: var(--accent-hover);
    border-color: var(--accent-hover);
    transform: translateY(-1px);
    box-shadow: 0 8px 30px rgba(200,69,27,0.3);
}

.btn-outline {
    background: transparent;
    color: rgba(255,255,255,0.85);
    border-color: rgba(255,255,255,0.3);
}

.btn-outline:hover {
    border-color: rgba(255,255,255,0.5);
    color: #fff;
}

.btn-full {
    width: 100%;
}

/* Hero Stats */
.hero-stats {
    position: relative;
    z-index: 2;
    display: flex;
    background: rgba(0,0,0,0.4);
    backdrop-filter: blur(16px);
    border-top: 1px solid rgba(255,255,255,0.08);
}

.stat {
    flex: 1;
    text-align: center;
    padding: 40px 24px;
    border-right: 1px solid rgba(255,255,255,0.06);
}

.stat:last-child {
    border-right: none;
}

.stat-number {
    font-size: 3rem;
    font-weight: 800;
    color: #fff;
    line-height: 1;
    letter-spacing: -0.03em;
}

.stat-plus {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--accent);
}

.stat-label {
    display: block;
    margin-top: 8px;
    font-size: 0.8rem;
    color: rgba(255,255,255,0.6);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

/* ===== Sections ===== */
.section {
    padding: 120px 0;
}

.section-header {
    margin-bottom: 72px;
}

.section-header.centered {
    text-align: center;
}

.section-tag {
    display: inline-block;
    font-size: 0.72rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.16em;
    color: var(--accent);
    margin-bottom: 16px;
}

.section-title {
    font-size: clamp(2rem, 4vw, 3.2rem);
    font-weight: 800;
    color: var(--primary);
    line-height: 1.1;
    letter-spacing: -0.03em;
}

.section-desc {
    margin-top: 20px;
    font-size: 1.05rem;
    color: var(--text-light);
    max-width: 560px;
    line-height: 1.7;
}

.section-header.centered .section-desc {
    margin-left: auto;
    margin-right: auto;
}

/* ===== About / Features ===== */
.about {
    background: var(--bg);
}

.about-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: start;
}

.about-text .section-header {
    margin-bottom: 32px;
}

.about-text .section-desc {
    margin-top: 16px;
}

.features-grid {
    display: flex;
    flex-direction: column;
    gap: 0;
}

.feature-card {
    display: flex;
    gap: 20px;
    padding: 28px 0;
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}

.feature-card:first-child {
    padding-top: 0;
}

.feature-card:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.feature-icon {
    width: 40px;
    height: 40px;
    flex-shrink: 0;
    color: var(--accent);
    margin-top: 2px;
}

.feature-card h3 {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 6px;
    color: var(--primary);
}

.feature-card p {
    font-size: 0.9rem;
    color: var(--text-light);
    line-height: 1.6;
}

/* Timeline */
.timeline {
    display: flex;
    justify-content: space-between;
    position: relative;
    margin-top: 48px;
}

.timeline::before {
    content: '';
    position: absolute;
    top: 8px;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--border);
}

.timeline-item {
    position: relative;
    text-align: left;
}

.timeline-item::before {
    content: '';
    display: block;
    width: 8px;
    height: 8px;
    background: var(--accent);
    border-radius: 50%;
    margin-bottom: 16px;
    position: relative;
    z-index: 1;
}

.timeline-year {
    font-size: 1.1rem;
    font-weight: 800;
    color: var(--primary);
    letter-spacing: -0.02em;
}

.timeline-text {
    font-size: 0.82rem;
    color: var(--text-light);
    margin-top: 4px;
}

/* ===== Services ===== */
.services {
    background: var(--bg-alt);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1px;
    background: var(--border);
    border: 1px solid var(--border);
}

.service-card {
    background: var(--bg);
    padding: 48px 36px;
    transition: var(--transition);
    position: relative;
}

.service-card:hover {
    background: var(--bg-alt);
}

.service-card:hover .service-number {
    color: var(--accent);
}

.service-number {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    letter-spacing: 0.1em;
    margin-bottom: 20px;
    transition: var(--transition);
}

.service-card h3 {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--primary);
}

.service-card p {
    font-size: 0.9rem;
    color: var(--text-light);
    line-height: 1.7;
}

/* ===== Projects ===== */
.projects {
    background: var(--bg);
}

.projects-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 32px;
}

.project-card {
    overflow: hidden;
    background: var(--bg);
    transition: var(--transition);
    position: relative;
}

.project-card:hover .project-image {
    transform: scale(1.02);
}

.project-image {
    height: 280px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    transition: transform 0.6s ease;
}

.project-placeholder-icon {
    width: 48px;
    height: 48px;
    color: rgba(255,255,255,0.2);
}

.project-info {
    padding: 24px 0 0;
}

.project-info h3 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 4px;
}

.project-info p {
    font-size: 0.85rem;
    color: var(--text-light);
    margin-bottom: 10px;
}

.project-tag {
    display: inline-block;
    font-size: 0.72rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

/* ===== Materials ===== */
.materials {
    background: var(--bg-dark);
    color: #fff;
}

.materials .section-tag {
    color: var(--accent);
}

.materials .section-title {
    color: #fff;
}

.materials .section-desc {
    color: rgba(255,255,255,0.5);
}

.materials-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0;
    border-top: 1px solid rgba(255,255,255,0.1);
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.material-card {
    padding: 48px 32px;
    text-align: left;
    transition: var(--transition);
    border-right: 1px solid rgba(255,255,255,0.06);
}

.material-card:last-child {
    border-right: none;
}

.material-card:hover {
    background: rgba(255,255,255,0.03);
}

.material-icon {
    width: 40px;
    height: 40px;
    margin-bottom: 24px;
    color: var(--accent);
}

.material-card h3 {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: #fff;
}

.material-card p {
    font-size: 0.85rem;
    color: rgba(255,255,255,0.45);
    line-height: 1.7;
}

/* ===== Partners ===== */
.partners {
    background: var(--bg-alt);
}

.partners-grid {
    display: flex;
    justify-content: center;
    gap: 48px;
    flex-wrap: wrap;
}

.partner-card {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    transition: var(--transition);
    padding: 16px 0;
}

.partner-card:hover {
    color: var(--text);
}

/* ===== Contact ===== */
.contact {
    background: var(--bg) !important;
    border-top: 1px solid var(--border);
}

.contact .section-title {
    color: var(--primary);
}

.contact .section-desc {
    color: var(--text-light);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: start;
}

.contact-details {
    margin-top: 32px;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.contact-item {
    display: flex;
    gap: 16px;
    align-items: flex-start;
}

.contact-item svg {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
    color: var(--accent);
    margin-top: 3px;
}

.contact-item strong {
    display: block;
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 500;
    margin-bottom: 2px;
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.contact-item p {
    font-size: 1rem;
    color: var(--text);
}

.work-hours {
    margin-top: 32px;
    padding-top: 24px;
    border-top: 1px solid var(--border);
}

.work-hours strong {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.work-hours p {
    margin-top: 4px;
    color: var(--text);
}

/* Form */
.contact-form {
    background: var(--bg-alt);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 40px;
}

.hidden {
    display: none;
}

.form-group {
    margin-bottom: 16px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 14px 18px;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text);
    font-family: inherit;
    font-size: 0.95rem;
    transition: var(--transition);
    outline: none;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--text-muted);
}

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

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* ===== Footer ===== */
.footer {
    background: var(--bg-dark);
    color: rgba(255,255,255,0.7);
    padding-top: 64px;
}

.footer-inner {
    display: flex;
    justify-content: space-between;
    gap: 48px;
    padding-bottom: 48px;
    border-bottom: 1px solid rgba(255,255,255,0.08);
}

.footer .logo-steel {
    color: #fff;
}

.footer .logo-construction {
    color: rgba(255,255,255,0.4);
}

.footer-brand p {
    margin-top: 12px;
    font-size: 0.85rem;
    color: rgba(255,255,255,0.35);
    max-width: 300px;
    line-height: 1.6;
}

.footer-links h4 {
    font-size: 0.72rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: rgba(255,255,255,0.35);
    margin-bottom: 16px;
}

.footer-links a {
    display: block;
    font-size: 0.88rem;
    color: rgba(255,255,255,0.55);
    padding: 4px 0;
    transition: var(--transition);
}

.footer-links a:hover {
    color: #fff;
}

.footer-bottom {
    padding: 24px 0;
}

.footer-bottom p {
    font-size: 0.78rem;
    color: rgba(255,255,255,0.2);
    text-align: center;
    letter-spacing: 0.02em;
}

/* ===== Animations ===== */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .about-layout {
        grid-template-columns: 1fr;
        gap: 48px;
    }

    .services-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .materials-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .material-card:nth-child(2) {
        border-right: none;
    }

    .footer-inner {
        flex-wrap: wrap;
    }

    .footer-brand {
        width: 100%;
    }
}

@media (max-width: 768px) {
    .nav {
        display: none;
        position: fixed;
        top: 72px;
        left: 0;
        right: 0;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(12px);
        flex-direction: column;
        padding: 24px;
        gap: 0;
        border-bottom: 1px solid var(--border);
        box-shadow: var(--shadow-lg);
    }

    .nav.open {
        display: flex;
    }

    .nav.open .nav-link {
        color: var(--text);
    }

    .nav-link {
        padding: 14px 0;
        font-size: 0.9rem;
        border-bottom: 1px solid var(--border);
    }

    .nav-link:last-child {
        border-bottom: none;
    }

    .menu-toggle {
        display: flex;
    }

    .hero-content {
        padding-top: 120px;
        padding-bottom: 60px;
    }

    .hero-stats {
        flex-direction: column;
    }

    .stat {
        border-right: none;
        border-bottom: 1px solid rgba(255,255,255,0.06);
        padding: 24px;
    }

    .stat:last-child {
        border-bottom: none;
    }

    .section {
        padding: 80px 0;
    }

    .services-grid {
        grid-template-columns: 1fr;
    }

    .projects-grid {
        grid-template-columns: 1fr;
    }

    .materials-grid {
        grid-template-columns: 1fr;
        border-left: 1px solid rgba(255,255,255,0.1);
        border-right: 1px solid rgba(255,255,255,0.1);
    }

    .material-card {
        border-right: none;
        border-bottom: 1px solid rgba(255,255,255,0.06);
    }

    .material-card:last-child {
        border-bottom: none;
    }

    .partners-grid {
        gap: 24px;
    }

    .contact-grid {
        grid-template-columns: 1fr;
        gap: 48px;
    }

    .timeline {
        flex-direction: column;
        gap: 24px;
        padding-left: 24px;
    }

    .timeline::before {
        width: 1px;
        height: 100%;
        left: 3px;
        top: 0;
    }

    .timeline-item {
        padding-left: 24px;
    }

    .timeline-item::before {
        position: absolute;
        left: 0;
        top: 4px;
        margin: 0;
    }

    .footer-inner {
        flex-direction: column;
        gap: 32px;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: flex-start;
    }
}