:root {
    /* Colors - Neutral Dark Theme */
    --color-bg-body: #050505;
    --color-bg-surface: #121212;
    --color-bg-surface-hover: #1e1e1e;
    --color-text-primary: #ffffff;
    --color-text-secondary: #a1a1aa;
    --color-accent: #ffffff;
    --color-border: #27272a;

    /* Typography */
    --font-primary: 'Inter', sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 2rem;
    --font-size-4xl: 3rem;
    --font-size-huge: 4.5rem;
    /* Hero title */

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 8rem;
    --container-width: 1200px;

    /* Effects */
    --radius-sm: 4px;
    --radius-md: 12px;
    --radius-lg: 24px;
    --shadow-soft: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
    --transition-fast: 0.2s cubic-bezier(0.2, 0.8, 0.2, 1);
    --transition-smooth: 0.4s cubic-bezier(0.2, 0.8, 0.2, 1);
    --blur-backdrop: 12px;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    background-color: var(--color-bg-body);
    color: var(--color-text-primary);
    font-family: var(--font-primary);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

ul {
    list-style: none;
}

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

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

/* Typography Utilities */
.overline {
    display: block;
    font-size: var(--font-size-xs);
    text-transform: uppercase;
    letter-spacing: 0.2em;
    font-weight: 600;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-sm);
}

.section-title {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    margin-bottom: var(--spacing-lg);
    text-align: center;
    letter-spacing: -0.02em;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 16px 40px;
    border-radius: 100px;
    font-weight: 500;
    font-size: var(--font-size-sm);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: 1px solid transparent;
}

.btn-primary {
    background-color: var(--color-text-primary);
    color: var(--color-bg-body);
}

.btn-primary:hover {
    background-color: #e5e5e5;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(255, 255, 255, 0.2);
}

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

.btn-outline:hover {
    border-color: var(--color-text-primary);
    background-color: rgba(255, 255, 255, 0.05);
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    padding: 24px 0;
    transition: background-color var(--transition-smooth), padding var(--transition-smooth);
}

.header.scrolled {
    background-color: rgba(5, 5, 5, 0.85);
    backdrop-filter: blur(var(--blur-backdrop));
    padding: 16px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

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

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

.logo-img {
    height: 32px;
    width: auto;
}

.logo-text {
    font-weight: 700;
    font-size: 1.25rem;
    letter-spacing: -0.02em;
}

.nav {
    display: none;
    /* Mobile first hidden */
}

@media (min-width: 768px) {
    .nav {
        display: block;
    }
}

.nav-list {
    display: flex;
    gap: 40px;
}

.nav-link {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    font-weight: 500;
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0%;
    height: 1px;
    background-color: var(--color-text-primary);
    transition: width var(--transition-fast);
}

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

.header-actions {
    display: flex;
    align-items: center;
    gap: 24px;
}

.lang-selector {
    display: none;
    /* Hide on mobile initially */
    gap: 12px;
}

@media (min-width: 768px) {
    .lang-selector {
        display: flex;
    }
}

.lang {
    font-size: var(--font-size-xs);
    font-weight: 600;
    color: var(--color-text-secondary);
    opacity: 0.6;
}

.lang.active,
.lang:hover {
    opacity: 1;
    color: var(--color-text-primary);
}

/* Mobile Menu Button */
.mobile-menu-btn {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    width: 24px;
    height: 18px;
    background: none;
    border: none;
    cursor: pointer;
    z-index: 1001;
}

@media (min-width: 768px) {
    .mobile-menu-btn {
        display: none;
    }
}

.bar {
    width: 100%;
    height: 2px;
    background-color: var(--color-text-primary);
    transition: all var(--transition-fast);
    transform-origin: center;
}

/* Mobile Menu Active State */
.mobile-menu-btn.active .bar:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
}

.mobile-menu-btn.active .bar:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active .bar:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
}

/* Mobile Menu Overlay */
.mobile-menu {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background-color: var(--color-bg-body);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-smooth);
}

.mobile-menu.active {
    opacity: 1;
    pointer-events: all;
}

.mobile-nav-list {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

.mobile-nav-link {
    display: block;
    font-size: var(--font-size-2xl);
    font-weight: 600;
    margin-bottom: 24px;
    color: var(--color-text-secondary);
}

.mobile-nav-link:hover {
    color: var(--color-text-primary);
}

.mobile-lang {
    display: flex;
    gap: 24px;
}

.mobile-lang a {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
}

.mobile-lang a.active {
    color: var(--color-text-primary);
    font-weight: 700;
}

/* Hero Section */
.hero {
    position: relative;
    height: 100vh;
    min-height: 600px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('assets/background.png');
    background-size: cover;
    background-position: center;
    z-index: -2;
    transform: scale(1.1);
    /* Subtle zoom for parallax later or just style */
}

/* Dark gradient overlay similar to reference but smoother */
.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg, rgba(5, 5, 5, 0.4) 0%, rgba(5, 5, 5, 0.7) 60%, rgba(5, 5, 5, 1) 100%);
    z-index: -1;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 900px;
}

.hero-title {
    font-size: var(--font-size-huge);
    line-height: 1.1;
    margin-bottom: var(--spacing-md);
    background: linear-gradient(to right, #fff 20%, #a1a1aa 100%);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    padding-bottom: 10px;
    /* Prevent clipped text */
}

.hero-subtitle {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
    max-width: 600px;
    margin: 0 auto;
    margin-bottom: var(--spacing-lg);
}

.scroll-indicator {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    color: var(--color-text-secondary);
    animation: bounce 2s infinite;
    opacity: 0.7;
    z-index: 10;
}

@keyframes bounce {

    0%,
    20%,
    50%,
    80%,
    100% {
        transform: translate(-50%, 0);
    }

    40% {
        transform: translate(-50%, -10px);
    }

    60% {
        transform: translate(-50%, -5px);
    }
}

/* About Section */
.about {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-bg-body);
}

.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: var(--spacing-lg);
}

.about-card {
    background-color: var(--color-bg-surface);
    padding: 40px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    transition: all var(--transition-smooth);
    text-align: left;
    position: relative;
    overflow: hidden;
}

.about-card:hover {
    transform: translateY(-5px);
    border-color: rgba(255, 255, 255, 0.2);
    box-shadow: var(--shadow-soft);
}

.card-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 60px;
    height: 60px;
    background-color: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
    margin-bottom: 24px;
    color: var(--color-text-primary);
}

.about-card h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
}

.about-card p {
    color: var(--color-text-secondary);
    font-size: var(--font-size-base);
}

.about-cta {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.about-summary {
    font-size: var(--font-size-xl);
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-md);
}

/* Footer */
.footer {
    padding: var(--spacing-lg) 0;
    border-top: 1px solid var(--color-border);
    background-color: var(--color-bg-body);
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-md);
}

.footer-links {
    display: flex;
    gap: 24px;
}

.footer-links a {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
}

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

.copyright {
    color: #444;
    font-size: var(--font-size-xs);
}

/* Animations using JS classes */
.fade-in-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in-up.visible {
    opacity: 1;
    transform: translateY(0);
}

.reveal-on-scroll {
    opacity: 0;
    transform: translateY(40px);
    transition: all 0.8s ease-out;
}

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

/* Stagger delays */
.delay-1 {
    transition-delay: 0.1s;
}

.delay-2 {
    transition-delay: 0.2s;
}

.delay-3 {
    transition-delay: 0.3s;
}

.delay-4 {
    transition-delay: 0.4s;
}

/* Responsive Overrides */
@media (max-width: 768px) {
    :root {
        --font-size-huge: 2.5rem;
        --spacing-lg: 3rem;
        --spacing-xl: 5rem;
    }

    .hero-content {
        padding: 0 10px;
    }

    .about-card {
        padding: 30px;
    }
}