:root {
    --bg-primary: #FFFFFF;
    --bg-secondary: #FAFAFA;
    --bg-tertiary: #F0F0F0;
    --bg-elevated: #E5E5E5;
    
    --accent-primary: #121212;
    --accent-primary-dim: #2A2A2A;
    --accent-primary-glow: rgba(18, 18, 18, 0.1);
    
    --accent-secondary: #6B46C1; 
    --accent-secondary-dim: #805AD5;
    --accent-secondary-glow: rgba(107, 70, 193, 0.2);

    --accent-red: #E53E3E; 
    
    --text-primary: #121212;
    --text-secondary: #4A4A4A;
    --text-tertiary: #717171;
    
    --board-light: #FFFFFF;
    --board-dark: #121212;
    
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 2rem;
    --space-xl: 3rem;
    --space-2xl: 4rem;
    --space-3xl: 6rem;
    
    --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    --transition-fast: 100ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: auto;
    background: var(--bg-primary);
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
    position: relative;
}

.tactical-bracket {
    position: relative;
}

.tactical-bracket::before,
.tactical-bracket::after {
    content: "";
    position: absolute;
    width: 20px;
    height: 20px;
    border-color: var(--accent-primary);
    border-style: solid;
    box-shadow: none;
}

.tactical-bracket-tl::before { top: 0; left: 0; border-width: 4px 0 0 4px; }
.tactical-bracket-tr::after { top: 0; right: 0; border-width: 4px 4px 0 0; }
.tactical-bracket-bl::before { bottom: 0; left: 0; border-width: 0 0 4px 4px; }
.tactical-bracket-br::after { bottom: 0; right: 0; border-width: 0 4px 4px 0; }

.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--bg-primary);
    border-bottom: 3px solid var(--accent-primary);
}

.nav-container {
    max-width: 1300px;
    margin: 0 auto;
    padding: 1.25rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-weight: 900;
    font-size: 1.5rem;
    color: var(--text-primary);
    text-decoration: none;
    letter-spacing: 0px;
    font-family: var(--font-mono);
    text-transform: uppercase;
}

.logo img {
    height: 36px;
    width: auto;
    border: 2px solid var(--accent-primary);
}

.nav-links {
    display: flex;
    gap: 1.5rem;
    align-items: center;
}

.nav-link {
    color: var(--text-primary);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 900;
    position: relative;
    font-family: var(--font-mono);
    text-transform: uppercase;
    border: 2px solid transparent;
    padding: 0.5rem 1rem;
}

.nav-link:hover {
    color: var(--bg-primary);
    background: var(--accent-primary);
    border: 2px solid var(--accent-primary);
}

.nav-link-primary {
    background: var(--accent-primary);
    color: var(--bg-primary) !important;
    padding: 0.75rem 1.75rem;
    border: 2px solid var(--accent-primary);
    font-weight: 900;
}

.nav-link-primary:hover {
    background: var(--bg-primary);
    color: var(--accent-primary) !important;
}

.hero {
    min-height: 100vh;
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: center;
    gap: var(--space-3xl);
    padding: calc(80px + var(--space-3xl)) var(--space-lg) var(--space-3xl);
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
    border-bottom: 3px solid var(--accent-primary);
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    background: var(--bg-primary);
    border: 2px solid var(--accent-primary);
    padding: 0.75rem 1.5rem;
    font-size: 0.8rem;
    font-family: var(--font-mono);
    color: var(--accent-primary);
    margin-bottom: var(--space-lg);
    font-weight: 900;
    text-transform: uppercase;
}

.badge-dot {
    width: 12px;
    height: 12px;
    background: var(--accent-primary);
}

.hero-title {
    font-size: clamp(3rem, 6vw, 4.5rem);
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: var(--space-md);
    font-family: var(--font-mono);
    text-transform: uppercase;
    border-bottom: 4px solid var(--accent-primary);
    padding-bottom: 1rem;
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin-bottom: var(--space-xl);
    line-height: 1.6;
}

.hero-cta {
    display: flex;
    gap: var(--space-md);
    margin-bottom: var(--space-3xl);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    padding: 1rem 2.25rem;
    font-weight: 900;
    font-size: 1.05rem;
    border: 2px solid var(--accent-primary);
    text-decoration: none;
    font-family: var(--font-mono);
    text-transform: uppercase;
}

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

.btn-primary:hover {
    background: var(--bg-primary);
    color: var(--accent-primary);
}

.btn-secondary {
    background: var(--bg-primary);
    color: var(--accent-primary);
}

.btn-secondary:hover {
    background: var(--accent-primary);
    color: var(--bg-primary);
}

.hero-stats {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.stat {
    text-align: center;
    border: 2px solid var(--accent-primary);
    padding: 1.5rem;
}

.stat-value {
    font-family: var(--font-mono);
    font-size: 1.75rem;
    font-weight: 900;
    color: var(--accent-primary);
}

.stat-label {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-top: var(--space-xs);
    font-weight: 900;
    text-transform: uppercase;
    font-family: var(--font-mono);
}

.stat-divider {
    width: 2px;
    height: 40px;
    background: var(--accent-primary);
}

.hero-visual {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    border: 3px solid var(--accent-primary);
    padding: 2rem;
    background: var(--bg-secondary);
}

.chess-board-preview {
    width: 280px;
    height: 280px;
    background: var(--board-light);
    display: grid;
    grid-template-rows: repeat(4, 1fr);
    border: 2px solid var(--accent-primary);
}

.board-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
}

.square {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    border: 1px solid var(--accent-primary);
}

.square.dark { background: var(--board-dark); color: white; }
.square.light { background: var(--board-light); color: black; }

section {
    padding: var(--space-3xl) 0;
    border-bottom: 3px solid var(--accent-primary);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-3xl);
}

.section-tag {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--accent-primary);
    font-weight: 900;
    margin-bottom: 1.5rem;
    padding: 0.5rem 1rem;
    background: var(--bg-primary);
    border: 2px solid var(--accent-primary);
    text-transform: uppercase;
}

.section-title {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    font-weight: 900;
    line-height: 1.1;
    font-family: var(--font-mono);
    text-transform: uppercase;
    border-bottom: 4px solid var(--accent-primary);
    padding-bottom: 1rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-xl);
}

.feature-card {
    background: var(--bg-primary);
    border: 3px solid var(--accent-primary);
    padding: 3rem;
}

.feature-icon {
    width: 64px;
    height: 64px;
    background: var(--accent-primary);
    color: var(--bg-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 2rem;
    font-size: 1.75rem;
    border: 2px solid var(--accent-primary);
}

.feature-card h3 {
    font-size: 1.5rem;
    font-weight: 900;
    margin-bottom: 1rem;
    font-family: var(--font-mono);
    text-transform: uppercase;
}

.feature-card p {
    font-size: 1rem;
    line-height: 1.7;
    font-family: var(--font-sans);
}

.modes-list {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.mode-item {
    display: grid;
    grid-template-columns: 80px 1fr auto;
    align-items: center;
    gap: 2rem;
    padding: 2.5rem;
    background: var(--bg-secondary);
    border: 3px solid var(--accent-primary);
}

.mode-number {
    font-family: var(--font-mono);
    font-size: 2rem;
    font-weight: 900;
}

.mode-content h3 {
    font-size: 1.5rem;
    font-weight: 900;
    font-family: var(--font-mono);
    text-transform: uppercase;
}

.mode-tag {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    font-weight: 900;
    padding: 0.75rem 1.5rem;
    background: var(--accent-primary);
    color: var(--bg-primary);
    text-transform: uppercase;
}

.download-card {
    background: var(--bg-primary);
    border: 3px solid var(--accent-primary);
    padding: 4rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.download-content h2 {
    font-size: 3rem;
    font-weight: 900;
    margin-bottom: 1.5rem;
    font-family: var(--font-mono);
    text-transform: uppercase;
    border-bottom: 3px solid var(--accent-primary);
    padding-bottom: 1rem;
}

.download-content p {
    font-size: 1.25rem;
    margin-bottom: 2.5rem;
    font-family: var(--font-sans);
}

.phone-mockup {
    width: 240px;
    height: 480px;
    background: var(--bg-primary);
    padding: 12px;
    border: 3px solid var(--accent-primary);
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: var(--bg-secondary);
    border: 2px solid var(--accent-primary);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--space-lg);
}

.screen-timer {
    font-family: var(--font-mono);
    font-size: 3rem;
    font-weight: 900;
    margin-bottom: var(--space-lg);
}

.screen-board {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2px;
    width: 120px;
}

.mini-square { aspect-ratio: 1; background: var(--board-light); border: 1px solid var(--accent-primary); }
.mini-square.dark { background: var(--board-dark); }

.ranking-grid {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.ranking-card {
    padding: 3rem 2.5rem;
    background: var(--bg-primary);
    display: flex;
    flex-direction: column;
    align-items: center;
    border: 4px solid var(--accent-primary);
    flex: 1;
    max-width: 300px;
    min-width: 240px;
    box-shadow: 12px 12px 0 var(--accent-primary);
    transition: var(--transition-base);
}

.ranking-card:hover {
    transform: translate(-4px, -4px);
    box-shadow: 16px 16px 0 var(--accent-primary);
}

.ranking-card img {
    height: 140px;
    width: auto;
    border: 2px solid var(--accent-primary);
    margin-bottom: 2rem;
    padding: 1rem;
    background: var(--bg-secondary);
}

.rank-name {
    font-family: var(--font-mono);
    font-weight: 900;
    text-transform: uppercase;
    border-top: 2px solid var(--accent-primary);
    padding-top: 1.5rem;
    width: 100%;
    text-align: center;
}

.footer {
    background: var(--bg-primary);
    border-top: 3px solid var(--accent-primary);
    padding: 6rem 0 3rem;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 3rem;
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-family: var(--font-mono);
    font-weight: 900;
    text-transform: uppercase;
}

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

.footer-bottom {
    margin-top: 4rem;
    padding-top: 2rem;
    border-top: 3px solid var(--accent-primary);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.visitor-counter {
    font-family: var(--font-mono);
    font-weight: 900;
    text-transform: uppercase;
    padding: 0.75rem 1.5rem;
    border: 2px solid var(--accent-primary);
}

@media (max-width: 968px) {
    .hero { grid-template-columns: 1fr; text-align: center; }
    .download-card { grid-template-columns: 1fr; text-align: center; }
    .ranking-grid { flex-direction: column; }
}

@media (max-width: 640px) {
    .hero-title { font-size: 2.5rem; }
    .nav-links { display: none; }
}