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

html {
    -webkit-text-size-adjust: 100%;
    -moz-text-size-adjust: 100%;
    text-size-adjust: 100%;
}

body {
    font-family: var(--font-body);
    font-size: var(--text-body);
    line-height: 1.6;
    color: var(--color-text);
    background: var(--surface-0);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

img,
picture,
video,
canvas,
svg {
    display: block;
    max-width: 100%;
    height: auto;
}

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

a:hover,
a:focus {
    text-decoration: underline;
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

button {
    font: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

/* ============================================
   Design Tokens
   ============================================ */
:root {
    /* Surface ladder: deep cyan-tinted near-blacks for data/gaming */
    --surface-0: #05070C;
    --surface-1: #0A0E14;
    --surface-2: #0F1520;
    --surface-3: #161D2B;
    --surface-4: #1E2636;
    --surface-5: #273344;
    
    /* Accent: luminous cyan */
    --color-accent: #38BDF8;
    --color-accent-muted: #6BACD4;
    
    /* Text */
    --color-text: #E5E7EB;
    --color-text-muted: #9CA3AF;
    
    /* Typography: fluid scale */
    --font-body: system-ui, -apple-system, "Segoe UI", "Roboto", sans-serif;
    --font-display: var(--font-body);
    
    --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
    --text-sm: clamp(0.875rem, 0.8rem + 0.375vw, 1rem);
    --text-body: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
    --text-lg: clamp(1.125rem, 1rem + 0.625vw, 1.375rem);
    --text-xl: clamp(1.25rem, 1.1rem + 0.75vw, 1.75rem);
    --text-2xl: clamp(1.5rem, 1.25rem + 1.25vw, 2.25rem);
    --text-3xl: clamp(1.875rem, 1.5rem + 1.875vw, 3rem);
    --text-4xl: clamp(2.25rem, 1.75rem + 2.5vw, 4rem);
    
    /* Spacing scale */
    --space-xs: clamp(0.5rem, 0.45rem + 0.25vw, 0.625rem);
    --space-sm: clamp(0.75rem, 0.65rem + 0.5vw, 1rem);
    --space-md: clamp(1rem, 0.85rem + 0.75vw, 1.5rem);
    --space-lg: clamp(1.5rem, 1.2rem + 1.5vw, 2.5rem);
    --space-xl: clamp(2rem, 1.5rem + 2.5vw, 3.5rem);
    --space-2xl: clamp(3rem, 2rem + 5vw, 6rem);
    
    /* Radius tokens */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-full: 999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.3);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.4), 0 2px 4px -2px rgb(0 0 0 / 0.4);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.5), 0 4px 6px -4px rgb(0 0 0 / 0.5);
    
    /* Layout */
    --container-max: 1280px;
    --container-padding: var(--space-md);
}

/* ============================================
   Utility Classes
   ============================================ */
.container {
    max-width: var(--container-max);
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--container-padding);
    padding-right: var(--container-padding);
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

.skip-link {
    position: absolute;
    top: -999px;
    left: 0;
    z-index: 9999;
    padding: var(--space-sm) var(--space-md);
    background: var(--color-accent);
    color: var(--surface-0);
    font-weight: 600;
}

.skip-link:focus {
    top: 0;
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-lg);
    font-size: var(--text-sm);
    font-weight: 600;
    border-radius: var(--radius-full);
    transition: all 0.2s;
    text-decoration: none;
    white-space: nowrap;
}

.btn:hover,
.btn:focus {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
    outline: none;
}

.btn--primary {
    background: var(--color-accent);
    color: var(--surface-0);
}

.btn--primary:hover,
.btn--primary:focus {
    background: var(--color-accent-muted);
}

.btn--ghost {
    background: transparent;
    color: var(--color-text);
    border: 1px solid var(--surface-4);
}

.btn--ghost:hover,
.btn--ghost:focus {
    background: var(--surface-3);
    border-color: var(--color-accent);
}

/* ============================================
   Header
   ============================================ */
.site-header {
    background: var(--surface-1);
    border-bottom: 1px solid var(--surface-3);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(8px);
}

.site-header__inner {
    display: grid;
    grid-template-columns: auto 1fr auto;
    align-items: center;
    gap: var(--space-md);
    padding-top: var(--space-sm);
    padding-bottom: var(--space-sm);
}

.site-header__logo {
    font-size: var(--text-xl);
    font-weight: 700;
    color: var(--color-accent);
    letter-spacing: -0.02em;
}

.site-header__toggle {
    display: none;
    font-size: var(--text-xl);
    color: var(--color-text);
    padding: var(--space-xs);
}

.site-header__nav ul {
    list-style: none;
    display: flex;
    gap: var(--space-md);
}

.site-header__nav a {
    color: var(--color-text);
    font-size: var(--text-sm);
    font-weight: 500;
    padding: var(--space-xs) 0;
}

.site-header__nav a:hover,
.site-header__nav a:focus {
    color: var(--color-accent);
}

.site-header__nav a[aria-current="page"] {
    color: var(--color-accent);
    border-bottom: 2px solid var(--color-accent);
}

.site-header__cta {
    display: flex;
    gap: var(--space-sm);
}

@media (max-width: 768px) {
    .site-header__toggle {
        display: block;
        grid-column: 3;
    }
    
    .site-header__nav {
        grid-column: 1 / -1;
        display: none;
    }
    
    .site-header__nav[aria-expanded="true"] {
        display: block;
    }
    
    .site-header__nav ul {
        flex-direction: column;
    }
    
    .site-header__cta {
        grid-column: 1 / -1;
        justify-content: stretch;
    }
    
    .site-header__cta .btn {
        flex: 1;
    }
}

/* ============================================
   Footer
   ============================================ */
.site-footer {
    background: var(--surface-1);
    border-top: 1px solid var(--surface-3);
    margin-top: auto;
    padding: var(--space-2xl) 0 var(--space-lg);
}

.site-footer__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-xl);
    margin-bottom: var(--space-xl);
}

.site-footer__section h2 {
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-accent);
    margin-bottom: var(--space-sm);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.site-footer__section ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.site-footer__section a {
    color: var(--color-text-muted);
    font-size: var(--text-sm);
}

.site-footer__section a:hover,
.site-footer__section a:focus {
    color: var(--color-accent);
}

.site-footer__legal {
    border-top: 1px solid var(--surface-3);
    padding-top: var(--space-lg);
    color: var(--color-text-muted);
    font-size: var(--text-xs);
    line-height: 1.8;
}

.site-footer__legal-text,
.site-footer__disclaimer {
    margin-bottom: var(--space-sm);
}

.site-footer__copyright {
    text-align: center;
    color: var(--color-text-muted);
    font-size: var(--text-xs);
}

/* ============================================
   Main Content
   ============================================ */
main {
    flex: 1;
}