/* ============================================
   Bloodhound Hydrogen Systems - Stylesheet
   ============================================ */

/* --- CSS Variables --- */
:root {
    --primary: #046bd2;
    --primary-dark: #045cb4;
    --primary-light: #e8f2fc;
    --dark: #1e293b;
    --dark-2: #334155;
    --gray: #64748b;
    --gray-light: #94a3b8;
    --border: #e2e8f0;
    --bg: #f8fafc;
    --white: #ffffff;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.08), 0 8px 10px -6px rgba(0,0,0,0.04);
    --radius: 8px;
    --radius-lg: 16px;
    --transition: 0.3s ease;
}

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

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.65;
    color: var(--dark-2);
    background: var(--white);
    -webkit-font-smoothing: antialiased;
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: color var(--transition);
}

ul {
    list-style: none;
}

h1, h2, h3, h4, h5, h6 {
    color: var(--dark);
    font-weight: 700;
    line-height: 1.3;
}

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

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 28px;
    font-size: 15px;
    font-weight: 600;
    border-radius: var(--radius);
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition);
    font-family: inherit;
    line-height: 1;
    white-space: nowrap;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    border-color: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border-color: var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: var(--white);
    transform: translateY(-1px);
}

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

.btn-sm {
    padding: 8px 20px;
    font-size: 14px;
}

/* --- Top Bar --- */
.top-bar {
    background: var(--dark);
    color: var(--white);
    font-size: 13px;
    padding: 8px 0;
}

.top-bar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.top-bar a {
    color: rgba(255,255,255,0.8);
}

.top-bar a:hover {
    color: var(--white);
}

/* --- Header --- */
.header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.97);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    transition: box-shadow var(--transition);
}

.header.scrolled {
    box-shadow: var(--shadow);
}

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

.logo img {
    height: 40px;
    width: auto;
}

.nav-list {
    display: flex;
    align-items: center;
    gap: 4px;
}

.nav-link {
    padding: 8px 16px;
    font-size: 15px;
    font-weight: 500;
    color: var(--dark-2);
    border-radius: var(--radius);
    transition: all var(--transition);
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary);
    background: var(--primary-light);
}

/* Dropdown */
.has-dropdown {
    position: relative;
}

.dropdown {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 220px;
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow-xl);
    border: 1px solid var(--border);
    padding: 8px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(8px);
    transition: all var(--transition);
}

.has-dropdown:hover .dropdown {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown a {
    display: block;
    padding: 10px 16px;
    font-size: 14px;
    color: var(--dark-2);
    border-radius: 6px;
    transition: all var(--transition);
}

.dropdown a:hover {
    background: var(--primary-light);
    color: var(--primary);
}

.header-cta {
    padding: 10px 24px;
    font-size: 14px;
}

/* Mobile Toggle */
.mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.mobile-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--dark);
    transition: all var(--transition);
    border-radius: 2px;
}

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

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

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

/* --- Hero --- */
.hero {
    position: relative;
    min-height: 85vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    background: linear-gradient(135deg, #0a1628 0%, #0d2847 40%, #0e3a6e 100%);
}

.hero-bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 20% 50%, rgba(4,107,210,0.15) 0%, transparent 60%),
        radial-gradient(ellipse at 80% 20%, rgba(4,107,210,0.1) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 80%, rgba(4,92,180,0.08) 0%, transparent 50%);
}

.hero-bg::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image:
        radial-gradient(circle at 1px 1px, rgba(255,255,255,0.03) 1px, transparent 0);
    background-size: 40px 40px;
}

.hero .container {
    position: relative;
    z-index: 2;
    text-align: center;
}

.hero-content {
    max-width: 780px;
    margin: 0 auto;
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 800;
    color: var(--white);
    line-height: 1.15;
    margin-bottom: 24px;
    letter-spacing: -0.02em;
}

.hero-title .highlight {
    background: linear-gradient(135deg, #4da3ff, #60b5ff);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-text {
    font-size: clamp(1rem, 2vw, 1.2rem);
    color: rgba(255,255,255,0.75);
    line-height: 1.7;
    margin-bottom: 40px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

.hero-buttons .btn-outline {
    color: var(--white);
    border-color: rgba(255,255,255,0.3);
}

.hero-buttons .btn-outline:hover {
    background: var(--white);
    color: var(--dark);
    border-color: var(--white);
}

.hero-scroll {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2;
}

.hero-scroll a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    border: 2px solid rgba(255,255,255,0.2);
    color: rgba(255,255,255,0.6);
    transition: all var(--transition);
    animation: bounce 2s infinite;
}

.hero-scroll a:hover {
    border-color: rgba(255,255,255,0.5);
    color: var(--white);
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(8px); }
}

/* --- Section Common --- */
.section {
    padding: 100px 0;
}

.section-label {
    display: inline-block;
    font-size: 13px;
    font-weight: 700;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 12px;
}

.section-title {
    font-size: clamp(1.75rem, 3vw, 2.5rem);
    font-weight: 800;
    color: var(--dark);
    margin-bottom: 20px;
    letter-spacing: -0.02em;
}

.section-desc {
    font-size: 1.1rem;
    color: var(--gray);
    max-width: 680px;
    margin: 0 auto;
    line-height: 1.7;
}

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: center;
}

.section-grid.reverse {
    direction: rtl;
}

.section-grid.reverse > * {
    direction: ltr;
}

.section-image img {
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    width: 100%;
    object-fit: cover;
    aspect-ratio: 4/3;
}

.section-content p {
    color: var(--gray);
    margin-bottom: 16px;
    line-height: 1.75;
}

.section-content .btn {
    margin-top: 16px;
}

/* --- History --- */
.history {
    background: var(--bg);
}

/* --- Services --- */
.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.service-card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 40px 32px;
    transition: all var(--transition);
}

.service-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
    border-color: transparent;
}

.service-icon {
    width: 64px;
    height: 64px;
    background: var(--primary-light);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 24px;
}

.service-icon svg {
    width: 32px;
    height: 32px;
    stroke: var(--primary);
}

.service-card h3 {
    font-size: 1.25rem;
    margin-bottom: 12px;
}

.service-card p {
    color: var(--gray);
    margin-bottom: 20px;
    line-height: 1.7;
}

.service-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 15px;
    font-weight: 600;
    color: var(--primary);
    transition: gap var(--transition);
}

.service-link:hover {
    gap: 10px;
}

/* --- Why Choose --- */
.why-choose {
    background: var(--dark);
}

.why-choose .section-label {
    color: rgba(255,255,255,0.6);
}

.why-choose .section-title {
    color: var(--white);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.feature-card {
    padding: 40px 32px;
    border-radius: var(--radius-lg);
    border: 1px solid rgba(255,255,255,0.08);
    background: rgba(255,255,255,0.03);
    transition: all var(--transition);
}

.feature-card:hover {
    border-color: rgba(255,255,255,0.15);
    background: rgba(255,255,255,0.06);
}

.feature-number {
    font-size: 3rem;
    font-weight: 800;
    color: var(--primary);
    opacity: 0.4;
    line-height: 1;
    margin-bottom: 20px;
}

.feature-card h4 {
    color: var(--white);
    font-size: 1.2rem;
    margin-bottom: 12px;
}

.feature-card p {
    color: rgba(255,255,255,0.6);
    line-height: 1.7;
}

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

/* --- Solutions --- */
.solutions-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.solution-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border);
    transition: all var(--transition);
}

.solution-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
    border-color: transparent;
}

.solution-img {
    overflow: hidden;
    aspect-ratio: 16/10;
}

.solution-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.solution-card:hover .solution-img img {
    transform: scale(1.05);
}

.solution-content {
    padding: 28px;
}

.solution-content h3 {
    font-size: 1.2rem;
    margin-bottom: 12px;
}

.solution-content p {
    color: var(--gray);
    font-size: 15px;
    margin-bottom: 20px;
    line-height: 1.7;
}

/* --- FAQ --- */
.faq {
    background: var(--bg);
}

.faq-layout {
    display: grid;
    grid-template-columns: 1fr 1.4fr;
    gap: 64px;
    align-items: start;
}

.faq-header p {
    color: var(--gray);
    margin-bottom: 28px;
    line-height: 1.7;
}

.faq-item {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    margin-bottom: 12px;
    background: var(--white);
    overflow: hidden;
    transition: border-color var(--transition);
}

.faq-item.active {
    border-color: var(--primary);
}

.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 18px 24px;
    background: none;
    border: none;
    cursor: pointer;
    font-family: inherit;
    font-size: 15px;
    font-weight: 600;
    color: var(--dark);
    text-align: left;
    gap: 16px;
    transition: color var(--transition);
}

.faq-item.active .faq-question {
    color: var(--primary);
}

.faq-chevron {
    flex-shrink: 0;
    transition: transform var(--transition);
}

.faq-item.active .faq-chevron {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease;
}

.faq-answer p {
    padding: 0 24px 18px;
    color: var(--gray);
    line-height: 1.7;
}

/* --- Values --- */
.values {
    background: linear-gradient(135deg, #0a1628 0%, #0d2847 40%, #0e3a6e 100%);
    text-align: center;
}

.values-content {
    max-width: 700px;
    margin: 0 auto;
}

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

.values-content p {
    color: rgba(255,255,255,0.7);
    font-size: 1.1rem;
    line-height: 1.75;
    margin-bottom: 36px;
}

/* --- News --- */
.news-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.news-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border);
    transition: all var(--transition);
}

.news-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
    border-color: transparent;
}

.news-img {
    aspect-ratio: 16/10;
    overflow: hidden;
}

.news-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.news-card:hover .news-img img {
    transform: scale(1.05);
}

.news-content {
    padding: 24px;
}

.news-tag {
    display: inline-block;
    font-size: 12px;
    font-weight: 600;
    color: var(--primary);
    background: var(--primary-light);
    padding: 4px 12px;
    border-radius: 20px;
    margin-bottom: 12px;
}

.news-content h3 {
    font-size: 1rem;
    line-height: 1.4;
    margin-bottom: 16px;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.news-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    font-weight: 600;
    color: var(--primary);
    transition: gap var(--transition);
}

.news-link:hover {
    gap: 10px;
}

/* --- CTA / Contact --- */
.cta {
    background: var(--bg);
}

.cta-content {
    max-width: 640px;
    margin: 0 auto;
    text-align: center;
}

.cta-content h2 {
    font-size: clamp(1.75rem, 3vw, 2.5rem);
    margin-bottom: 12px;
}

.cta-content > p {
    color: var(--gray);
    font-size: 1.1rem;
    margin-bottom: 40px;
}

.cta-form form {
    text-align: left;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 16px;
}

.cta-form input,
.cta-form textarea {
    width: 100%;
    padding: 14px 18px;
    font-size: 15px;
    font-family: inherit;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--white);
    color: var(--dark);
    transition: border-color var(--transition);
    outline: none;
}

.cta-form input:focus,
.cta-form textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(4,107,210,0.1);
}

.cta-form textarea {
    margin-bottom: 16px;
    resize: vertical;
}

.cta-form .btn {
    width: 100%;
}

.form-status {
    font-size: 14px;
    padding: 0;
    margin-bottom: 12px;
    border-radius: var(--radius);
    line-height: 1.5;
    display: none;
}

.form-status--error {
    display: block;
    color: #dc2626;
    background: #fef2f2;
    border: 1px solid #fecaca;
    padding: 12px 16px;
}

.form-status--success {
    display: block;
    color: #16a34a;
    background: #f0fdf4;
    border: 1px solid #bbf7d0;
    padding: 12px 16px;
}

/* --- Footer --- */
.footer {
    background: var(--dark);
    color: rgba(255,255,255,0.7);
    padding: 80px 0 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1.5fr;
    gap: 48px;
    padding-bottom: 48px;
}

.footer-logo {
    height: 36px;
    margin-bottom: 16px;
    filter: brightness(0) invert(1);
}

.footer-brand p {
    font-size: 15px;
    line-height: 1.7;
}

.footer-links h4,
.footer-contact h4 {
    color: var(--white);
    font-size: 15px;
    font-weight: 700;
    margin-bottom: 20px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.footer-links ul li {
    margin-bottom: 10px;
}

.footer-links a {
    font-size: 15px;
    color: rgba(255,255,255,0.6);
    transition: color var(--transition);
}

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

.footer-contact ul li {
    display: flex;
    gap: 10px;
    margin-bottom: 14px;
    font-size: 14px;
    align-items: flex-start;
}

.footer-contact svg {
    flex-shrink: 0;
    margin-top: 3px;
    color: var(--primary);
}

.footer-contact a {
    color: rgba(255,255,255,0.6);
}

.footer-contact a:hover {
    color: var(--white);
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.08);
    padding: 24px 0;
    text-align: center;
    font-size: 14px;
    color: rgba(255,255,255,0.4);
}

/* --- Scroll to Top --- */
.scroll-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 44px;
    height: 44px;
    background: var(--primary);
    color: var(--white);
    border: none;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transform: translateY(16px);
    transition: all var(--transition);
    box-shadow: var(--shadow-lg);
    z-index: 99;
}

.scroll-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.scroll-top:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}

/* --- Reveal Animations --- */
.reveal-up,
.reveal-left,
.reveal-right {
    opacity: 0;
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal-up {
    transform: translateY(40px);
}

.reveal-left {
    transform: translateX(-40px);
}

.reveal-right {
    transform: translateX(40px);
}

.reveal-up.revealed,
.reveal-left.revealed,
.reveal-right.revealed {
    opacity: 1;
    transform: translate(0);
}

/* ============================================
   Responsive
   ============================================ */

@media (max-width: 1024px) {
    .news-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

@media (max-width: 920px) {
    .section {
        padding: 72px 0;
    }

    .nav {
        position: fixed;
        top: 0;
        right: -100%;
        width: 300px;
        height: 100vh;
        background: var(--white);
        box-shadow: var(--shadow-xl);
        padding: 80px 24px 24px;
        transition: right var(--transition);
        z-index: 999;
        overflow-y: auto;
    }

    .nav.open {
        right: 0;
    }

    .nav-list {
        flex-direction: column;
        align-items: stretch;
        gap: 0;
    }

    .nav-link {
        padding: 14px 16px;
        font-size: 16px;
        border-bottom: 1px solid var(--border);
    }

    .dropdown {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        box-shadow: none;
        border: none;
        padding: 0 0 0 16px;
    }

    .header-cta {
        display: none;
    }

    .mobile-toggle {
        display: flex;
        z-index: 1001;
    }

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

    .section-grid.reverse {
        direction: ltr;
    }

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

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

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

@media (max-width: 768px) {
    .top-bar .container {
        flex-direction: column;
        gap: 4px;
        text-align: center;
    }

    .hero {
        min-height: 70vh;
    }

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

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

@media (max-width: 480px) {
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

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

/* --- Mobile overlay --- */
.nav-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.4);
    z-index: 998;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition);
}

.nav-overlay.active {
    opacity: 1;
    visibility: visible;
}