/* ================================================================
   FengiaTech — Smart Lock Manufacturer Website
   Stylesheet
   ================================================================ */

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

:root {
    /* Color Palette */
    --navy-900: #060d1a;
    --navy-800: #0a192f;
    --navy-700: #0e2240;
    --navy-600: #112240;
    --navy-500: #1a3055;
    --navy-400: #233e6e;
    --gold-500: #c5a47e;
    --gold-400: #d4b896;
    --gold-300: #e0c9a8;
    --silver-400: #b8c2cc;
    --gray-100: #f5f6f8;
    --gray-200: #e8eaef;
    --gray-300: #d1d5db;
    --gray-500: #6b7280;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --white: #ffffff;

    /* Typography */
    --font-heading: 'Montserrat', sans-serif;
    --font-body: 'Inter', sans-serif;

    /* Spacing */
    --container-max: 1200px;
    --section-padding: 100px 0;
    --radius: 8px;
    --radius-lg: 16px;

    /* Transitions */
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.6;
    color: var(--gray-800);
    background: var(--gray-100);
    overflow-x: hidden;
}

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

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

ul {
    list-style: none;
}

/* ---------- Container ---------- */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 24px;
}

/* ---------- Buttons ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-heading);
    font-weight: 600;
    font-size: 14px;
    letter-spacing: 0.5px;
    text-transform: uppercase;
    padding: 12px 28px;
    border-radius: var(--radius);
    cursor: pointer;
    border: none;
    transition: var(--transition);
    white-space: nowrap;
}

.btn-gold {
    background: linear-gradient(135deg, var(--gold-500), var(--gold-400));
    color: var(--navy-900);
    box-shadow: 0 4px 15px rgba(197, 164, 126, 0.3);
}

.btn-gold:hover {
    background: linear-gradient(135deg, var(--gold-400), var(--gold-300));
    box-shadow: 0 6px 20px rgba(197, 164, 126, 0.45);
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: var(--white);
    border: 2px solid var(--white);
}

.btn-outline:hover {
    background: var(--white);
    color: var(--navy-900);
    transform: translateY(-2px);
}

.btn-lg {
    padding: 16px 36px;
    font-size: 15px;
}

.btn-full {
    width: 100%;
}

/* ---------- Header ---------- */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(6, 13, 26, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(197, 164, 126, 0.15);
    transition: var(--transition);
}

.header.scrolled {
    background: rgba(6, 13, 26, 0.95);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

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

.logo {
    font-family: var(--font-heading);
    font-weight: 800;
    font-size: 24px;
    letter-spacing: -0.5px;
    color: var(--white);
}

.logo-text {
    color: var(--white);
}

.logo-accent {
    color: var(--gold-500);
}

.nav-list {
    display: flex;
    gap: 36px;
    align-items: center;
}

.nav-link {
    font-family: var(--font-heading);
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-200);
    transition: var(--transition);
    position: relative;
    padding: 4px 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gold-500);
    transition: var(--transition);
}

.nav-link:hover {
    color: var(--white);
}

.nav-link:hover::after {
    width: 100%;
}

.nav-link.active {
    color: var(--gold-500);
}

.btn-quote {
    margin-left: 8px;
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 6px;
    z-index: 1001;
}

.hamburger span {
    display: block;
    width: 26px;
    height: 3px;
    background: var(--white);
    border-radius: 2px;
    transition: var(--transition);
}

.hamburger.active span:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
}

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

.hamburger.active span:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
}

/* ---------- Section Base ---------- */
.section {
    padding: var(--section-padding);
}

.section-dark {
    background: var(--navy-800);
    color: var(--gray-200);
}

.section-light {
    background: var(--gray-100);
    color: var(--gray-800);
}

.section-header {
    text-align: center;
    max-width: 720px;
    margin: 0 auto 64px;
}

.section-eyebrow {
    font-family: var(--font-heading);
    font-size: 13px;
    font-weight: 600;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: var(--gold-500);
    margin-bottom: 12px;
}

.section-eyebrow-light {
    color: var(--gold-400);
}

.section-title {
    font-family: var(--font-heading);
    font-size: 38px;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 16px;
}

.section-dark .section-title {
    color: var(--white);
}

.section-title-light {
    color: var(--white) !important;
}

.section-desc {
    font-size: 17px;
    line-height: 1.7;
    color: var(--gray-500);
}

.section-dark .section-desc {
    color: var(--silver-400);
}

/* ---------- Hero ---------- */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, var(--navy-900) 0%, var(--navy-700) 50%, var(--navy-600) 100%);
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('https://picsum.photos/seed/smartlockhero/1920/1080') center/cover no-repeat;
    opacity: 0.15;
    z-index: 0;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(ellipse at 30% 50%, rgba(10, 25, 47, 0.7) 0%, rgba(6, 13, 26, 0.9) 60%);
    z-index: 1;
}

.hero-content {
    position: relative;
    z-index: 2;
    padding-top: 72px;
}

.hero-eyebrow {
    display: inline-block;
    font-family: var(--font-heading);
    font-size: 14px;
    font-weight: 600;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: var(--gold-500);
    margin-bottom: 24px;
    padding: 6px 18px;
    border: 1px solid rgba(197, 164, 126, 0.3);
    border-radius: 30px;
}

.hero-title {
    font-family: var(--font-heading);
    font-size: 60px;
    font-weight: 800;
    line-height: 1.15;
    color: var(--white);
    margin-bottom: 24px;
    text-shadow: 0 2px 30px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
    font-size: 20px;
    color: var(--silver-400);
    margin-bottom: 40px;
    max-width: 680px;
    line-height: 1.6;
}

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

.hero-scroll {
    margin-top: 80px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
}

.hero-scroll span {
    font-size: 12px;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: var(--silver-400);
    opacity: 0.7;
}

.scroll-line {
    width: 2px;
    height: 50px;
    background: linear-gradient(to bottom, var(--gold-500), transparent);
    animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
    0%, 100% { transform: scaleY(1); opacity: 1; }
    50% { transform: scaleY(0.5); opacity: 0.5; }
}

/* ---------- Advantages ---------- */
.advantage-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.advantage-card {
    background: var(--navy-600);
    border: 1px solid rgba(197, 164, 126, 0.12);
    border-radius: var(--radius-lg);
    padding: 40px 28px;
    text-align: center;
    transition: var(--transition);
}

.advantage-card:hover {
    border-color: var(--gold-500);
    transform: translateY(-6px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
}

.advantage-icon {
    width: 56px;
    height: 56px;
    margin: 0 auto 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gold-500);
    background: rgba(197, 164, 126, 0.08);
    border-radius: 50%;
    padding: 14px;
}

.advantage-number {
    font-family: var(--font-heading);
    font-size: 42px;
    font-weight: 800;
    color: var(--white);
    margin-bottom: 8px;
    line-height: 1;
}

.advantage-label {
    font-family: var(--font-heading);
    font-size: 16px;
    font-weight: 600;
    color: var(--gray-200);
    margin-bottom: 4px;
    line-height: 1.4;
}

.advantage-category {
    font-size: 13px;
    letter-spacing: 1px;
    text-transform: uppercase;
    color: var(--gold-500);
    font-weight: 600;
}

/* ---------- Products ---------- */
.product-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.product-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.06);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.product-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 16px 50px rgba(0, 0, 0, 0.12);
}

.product-img {
    overflow: hidden;
    aspect-ratio: 3 / 2;
    background: var(--gray-200);
}

.product-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-slow);
}

.product-card:hover .product-img img {
    transform: scale(1.08);
}

.product-body {
    padding: 24px;
    display: flex;
    flex-direction: column;
    flex: 1;
}

.product-name {
    font-family: var(--font-heading);
    font-size: 20px;
    font-weight: 600;
    color: var(--navy-800);
    margin-bottom: 10px;
}

.product-desc {
    font-size: 14px;
    color: var(--gray-500);
    line-height: 1.6;
    margin-bottom: 18px;
    flex: 1;
}

.product-link {
    font-family: var(--font-heading);
    font-size: 14px;
    font-weight: 600;
    color: var(--gold-500);
    transition: var(--transition);
}

.product-link:hover {
    color: var(--navy-800);
    letter-spacing: 0.5px;
}

/* ---------- About Us ---------- */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: center;
}

.about-img {
    position: relative;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 10px 50px rgba(0, 0, 0, 0.4);
}

.about-img img {
    width: 100%;
    aspect-ratio: 7 / 5;
    object-fit: cover;
}

.about-img-badge {
    position: absolute;
    bottom: 24px;
    right: 24px;
    background: linear-gradient(135deg, var(--gold-500), var(--gold-400));
    padding: 16px 24px;
    border-radius: var(--radius);
    text-align: center;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

.badge-number {
    display: block;
    font-family: var(--font-heading);
    font-size: 24px;
    font-weight: 800;
    color: var(--navy-900);
}

.badge-text {
    display: block;
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--navy-900);
    opacity: 0.8;
}

.about-text {
    font-size: 16px;
    line-height: 1.8;
    color: var(--silver-400);
    margin-bottom: 18px;
}

.about-list {
    margin-top: 28px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
}

.about-list li {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 15px;
    color: var(--gray-200);
    font-weight: 500;
}

.about-list svg {
    width: 20px;
    height: 20px;
    color: var(--gold-500);
    flex-shrink: 0;
}

/* ---------- Quality Control ---------- */
.quality-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.quality-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    text-align: center;
    transition: var(--transition);
    border-top: 4px solid transparent;
    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.05);
}

.quality-card:hover {
    border-top-color: var(--gold-500);
    transform: translateY(-6px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.1);
}

.quality-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--navy-700);
    background: var(--gray-100);
    border-radius: 50%;
    padding: 15px;
}

.quality-card:hover .quality-icon {
    background: rgba(197, 164, 126, 0.1);
    color: var(--gold-500);
}

.quality-title {
    font-family: var(--font-heading);
    font-size: 17px;
    font-weight: 600;
    color: var(--navy-800);
    margin-bottom: 8px;
}

.quality-stat {
    font-family: var(--font-heading);
    font-size: 28px;
    font-weight: 800;
    color: var(--gold-500);
    margin-bottom: 12px;
    line-height: 1;
}

.quality-desc {
    font-size: 14px;
    color: var(--gray-500);
    line-height: 1.6;
}

/* ---------- Stats ---------- */
.section-stat {
    background: linear-gradient(135deg, var(--navy-900), var(--navy-700));
    position: relative;
    overflow: hidden;
}

.section-stat::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(197, 164, 126, 0.06), transparent 70%);
    z-index: 0;
}

.stat-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    position: relative;
    z-index: 1;
}

.stat-card {
    text-align: center;
    padding: 40px 20px;
    border-right: 1px solid rgba(197, 164, 126, 0.15);
}

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

.stat-number {
    font-family: var(--font-heading);
    font-size: 52px;
    font-weight: 800;
    color: var(--gold-500);
    line-height: 1;
    margin-bottom: 12px;
}

.stat-label {
    font-family: var(--font-heading);
    font-size: 16px;
    font-weight: 500;
    color: var(--silver-400);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* ---------- Contact ---------- */
.contact-grid {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 40px;
}

.contact-form-wrapper {
    background: var(--white);
    padding: 40px;
    border-radius: var(--radius-lg);
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.06);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-family: var(--font-heading);
    font-size: 14px;
    font-weight: 600;
    color: var(--navy-800);
    margin-bottom: 8px;
}

.required {
    color: #e53e3e;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    font-family: var(--font-body);
    font-size: 15px;
    color: var(--gray-800);
    background: var(--gray-100);
    border: 2px solid transparent;
    border-radius: var(--radius);
    transition: var(--transition);
    outline: none;
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--gold-500);
    background: var(--white);
    box-shadow: 0 0 0 3px rgba(197, 164, 126, 0.1);
}

.form-group input.invalid,
.form-group textarea.invalid {
    border-color: #e53e3e;
    background: #fef5f5;
}

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

.form-error {
    display: block;
    font-size: 13px;
    color: #e53e3e;
    margin-top: 6px;
    min-height: 18px;
}

.form-success {
    display: none;
    align-items: center;
    gap: 12px;
    margin-top: 20px;
    padding: 16px 20px;
    background: #f0fdf4;
    border: 1px solid #bbf7d0;
    border-radius: var(--radius);
    color: #15803d;
}

.form-success.show {
    display: flex;
    animation: fadeIn 0.4s ease;
}

.form-success svg {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Contact Info */
.contact-info-card {
    background: var(--navy-800);
    padding: 40px 32px;
    border-radius: var(--radius-lg);
    height: 100%;
}

.contact-info-title {
    font-family: var(--font-heading);
    font-size: 22px;
    font-weight: 700;
    color: var(--white);
    margin-bottom: 28px;
    padding-bottom: 20px;
    border-bottom: 1px solid rgba(197, 164, 126, 0.2);
}

.contact-info-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 26px;
}

.contact-info-item:last-child {
    margin-bottom: 0;
}

.contact-info-icon {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(197, 164, 126, 0.1);
    border-radius: 50%;
    color: var(--gold-500);
    padding: 11px;
    flex-shrink: 0;
}

.contact-info-item h4 {
    font-family: var(--font-heading);
    font-size: 14px;
    font-weight: 600;
    color: var(--gold-500);
    margin-bottom: 4px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.contact-info-item p {
    font-size: 15px;
    color: var(--silver-400);
    line-height: 1.5;
}

/* ---------- Footer ---------- */
.footer {
    background: var(--navy-900);
    color: var(--silver-400);
    padding: 60px 0 24px;
}

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

.footer-brand {
    text-align: center;
}

.footer-brand .logo-text {
    font-family: var(--font-heading);
    font-size: 28px;
    font-weight: 800;
    color: var(--white);
}

.footer-brand p {
    margin-top: 12px;
    font-size: 14px;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 32px;
    flex-wrap: wrap;
}

.footer-links a {
    font-family: var(--font-heading);
    font-size: 14px;
    font-weight: 500;
    color: var(--silver-400);
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--gold-500);
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    padding-top: 24px;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-bottom p {
    font-size: 13px;
    color: var(--gray-500);
}

.footer-legal {
    display: flex;
    gap: 12px;
    align-items: center;
}

.footer-legal a {
    font-size: 13px;
    color: var(--gray-500);
    transition: var(--transition);
}

.footer-legal a:hover {
    color: var(--gold-500);
}

.footer-legal span {
    color: var(--gray-700);
}

/* ---------- Reveal Animation ---------- */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ---------- Responsive: Tablet (<= 992px) ---------- */
@media (max-width: 992px) {
    .hero-title {
        font-size: 44px;
    }

    .hero-subtitle {
        font-size: 17px;
    }

    .section-title {
        font-size: 32px;
    }

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

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

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

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

    .stat-card {
        border-right: none;
        border-bottom: 1px solid rgba(197, 164, 126, 0.15);
    }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

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

    .section {
        padding: 70px 0;
    }

    .section-header {
        margin-bottom: 48px;
    }
}

/* ---------- Responsive: Mobile (<= 768px) ---------- */
@media (max-width: 768px) {
    .nav {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: var(--navy-900);
        flex-direction: column;
        justify-content: flex-start;
        padding: 90px 32px 32px;
        transition: right 0.4s cubic-bezier(0.4, 0, 0.2, 1);
        z-index: 999;
    }

    .nav.active {
        right: 0;
    }

    .nav-list {
        flex-direction: column;
        gap: 0;
        width: 100%;
    }

    .nav-list li {
        width: 100%;
        border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }

    .nav-link {
        display: block;
        padding: 16px 0;
        font-size: 16px;
    }

    .nav-link::after {
        display: none;
    }

    .btn-quote {
        display: none;
    }

    .hamburger {
        display: flex;
    }

    .hero-title {
        font-size: 34px;
    }

    .hero-subtitle {
        font-size: 16px;
    }

    .hero-buttons {
        flex-direction: column;
        width: 100%;
    }

    .hero-buttons .btn {
        width: 100%;
    }

    .hero-scroll {
        display: none;
    }

    .section-title {
        font-size: 26px;
    }

    .section-desc {
        font-size: 15px;
    }

    .advantage-grid,
    .product-grid,
    .quality-grid,
    .stat-grid {
        grid-template-columns: 1fr;
    }

    .stat-card {
        border-bottom: 1px solid rgba(197, 164, 126, 0.15);
    }

    .about-list {
        grid-template-columns: 1fr;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .contact-form-wrapper {
        padding: 24px;
    }

    .contact-info-card {
        padding: 28px 24px;
    }

    .footer-links {
        gap: 20px;
    }

    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }

    .container {
        padding: 0 20px;
    }
}

/* ---------- Responsive: Small Mobile (<= 480px) ---------- */
@media (max-width: 480px) {
    .hero-title {
        font-size: 28px;
    }

    .section-title {
        font-size: 22px;
    }

    .advantage-card,
    .quality-card {
        padding: 28px 20px;
    }

    .advantage-number,
    .quality-stat {
        font-size: 34px;
    }

    .stat-number {
        font-size: 40px;
    }
}