/* Renzlab Common Styles - Shared across all pages */

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

:root {
    --bg-dark: #0a0e1a;
    --bg-card: #1a1f2e;
    --text-primary: #ffffff;
    --text-secondary: #aaa;
    --accent-green: #00ff00;
    --border-color: #2a2f3e;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Skip to content link for accessibility */
.skip-to-content {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--accent-green);
    color: var(--bg-dark);
    padding: 0.5rem 1rem;
    text-decoration: none;
    font-weight: 600;
    z-index: 10000;
}

.skip-to-content:focus {
    top: 0;
}

/* Animated Background */
.background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #0a0e1a 0%, #1a1f2e 50%, #0f1419 100%);
    z-index: -1;
}

.grid-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        linear-gradient(rgba(0, 255, 0, 0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 255, 0, 0.02) 1px, transparent 1px);
    background-size: 50px 50px;
    z-index: -1;
    will-change: transform;
}

/* Header */
header {
    background: rgba(26, 31, 46, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 2px solid var(--accent-green);
    padding: 1.5rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 4px 20px rgba(0, 255, 0, 0.1);
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--accent-green);
    text-transform: uppercase;
    letter-spacing: 0.2rem;
    text-shadow: 0 0 10px rgba(0, 255, 0, 0.5);
    text-decoration: none;
}

.logo:focus {
    outline: 2px solid var(--accent-green);
    outline-offset: 4px;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 2rem;
}

nav a {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    padding: 0.5rem 1rem;
    border-radius: 5px;
}

nav a:hover,
nav a:focus {
    color: var(--accent-green);
    background: rgba(0, 255, 0, 0.1);
    box-shadow: 0 0 10px rgba(0, 255, 0, 0.2);
    outline: none;
}

/* Footer */
footer {
    background: rgba(26, 31, 46, 0.95);
    border-top: 2px solid var(--accent-green);
    padding: 2rem;
    text-align: center;
    margin-top: 4rem;
}

footer p {
    color: var(--text-secondary);
}

/* Accessibility - Reduced Motion */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Responsive */
@media (max-width: 768px) {
    .header-container {
        flex-direction: column;
        gap: 1rem;
    }

    nav ul {
        flex-direction: column;
        gap: 0.5rem;
        text-align: center;
    }
}