:root { 
    --zinc-50: #fafafa;
    --zinc-100: #f4f4f5;
    --zinc-200: #e4e4e7;
    --zinc-300: #d4d4d8;
    --zinc-400: #a1a1aa;
    --zinc-500: #71717a;
    --zinc-600: #52525b;
    --zinc-700: #3f3f46;
    --zinc-800: #27272a;
    --zinc-900: #18181b;
    --zinc-950: #08080a; /* Laboratory Grade Deep Black */
    
    --clinical-emerald: #10b981; 
    --research-indigo: #6366f1;
    --caution-amber: #f59e0b;
    
    --blue-500: var(--clinical-emerald); 
    --blue-600: #059669; /* Emerald Dark */
    --blue-400: #34d399; /* Emerald Light */
    
    --glass-bg: rgba(255, 255, 255, 0.015);
    --glass-border: rgba(255, 255, 255, 0.03);
    --glass-blur: blur(20px);
    
    --accent-gradient: linear-gradient(135deg, var(--clinical-emerald) 0%, var(--research-indigo) 100%);
    --text-gradient: linear-gradient(180deg, #ffffff 0%, #94a3b8 100%);
}

/* Global Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

html {
    scroll-behavior: smooth;
}

body { 
    background: var(--zinc-950); 
    background-image: 
        radial-gradient(circle at 2px 2px, rgba(255,255,255,0.02) 1px, transparent 0);
    background-size: 40px 40px;
    color: #94a3b8; 
    font-family: 'Inter', system-ui, -apple-system, sans-serif; 
    overflow-x: hidden; 
    line-height: 1.6;
}

h1, h2, h3, h4, h5, h6, .brand { 
    font-family: 'Outfit', sans-serif; 
    letter-spacing: -0.04em; 
    color: #fff;
}

/* Typography Utilities */
.text-gradient {
    background: var(--text-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Clinical Card System */
.glass {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    position: relative;
    overflow: hidden;
}

/* Laboratory Measure Marks */
.glass::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 20px;
    height: 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
    border-left: 1px solid rgba(255,255,255,0.1);
    pointer-events: none;
}

.glass::after {
    content: '';
    position: absolute;
    bottom: 0;
    right: 0;
    width: 20px;
    height: 20px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
    border-right: 1px solid rgba(255,255,255,0.1);
    pointer-events: none;
}

.glass-hover {
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.glass-hover:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: rgba(16, 185, 129, 0.2);
    box-shadow: 0 20px 40px -20px rgba(0, 0, 0, 0.5);
}

/* Navigation System */
.nav-pill { 
    background: rgba(5, 5, 7, 0.4);
    backdrop-filter: blur(32px);
    -webkit-backdrop-filter: blur(32px);
    border: 1px solid rgba(255, 255, 255, 0.08);
    box-shadow: 0 10px 40px -10px rgba(0, 0, 0, 0.8);
}

.nav-link {
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 4px;
    left: 50%;
    width: 0;
    height: 1.5px;
    background: var(--blue-500);
    transition: all 0.3s ease;
    transform: translateX(-50%);
    opacity: 0;
}

.nav-link:hover::after, .nav-link.active::after {
    width: 20px;
    opacity: 1;
}

.nav-link.active {
    color: #fff !important;
}

/* View Section Transitions */
.view-section { 
    display: none; 
    opacity: 0; 
}

@keyframes view-enter {
    from { opacity: 0; transform: translateY(20px) scale(0.98); }
    to { opacity: 1; transform: translateY(0) scale(1); }
}

@keyframes slide-up {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes fade-in {
    from { opacity: 0; }
    to { opacity: 1; }
}

.animate-slide-up {
    animation: slide-up 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.animate-fade-in {
    animation: fade-in 0.8s ease forwards;
}

.view-section.active { 
    display: block; 
    animation: view-enter 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

/* Modal System */
#modal-overlay { 
    background: rgba(2, 2, 4, 0.4); 
    backdrop-filter: blur(20px); 
    -webkit-backdrop-filter: blur(20px);
    z-index: 1000; 
    opacity: 0;
    transition: opacity 0.4s ease;
}

#modal-overlay:not(.hidden) {
    display: flex;
    opacity: 1;
}

.modal-content { 
    max-width: 1000px; 
    width: 100%; 
    transition: all 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* Custom UI Elements */
.skeleton {
    background: linear-gradient(90deg, var(--zinc-900) 25%, var(--zinc-800) 50%, var(--zinc-900) 75%);
    background-size: 200% 100%;
    animation: skeleton-loading 1.5s infinite;
    border-radius: 2rem;
}

@keyframes skeleton-loading {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

.no-scrollbar::-webkit-scrollbar {
    display: none;
}

.no-scrollbar {
    -ms-overflow-style: none;
    scrollbar-width: none;
}

/* Table & Details Styling */
details > summary { 
    list-style: none; 
    outline: none; 
}

details > summary::-webkit-details-marker { 
    display: none; 
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: var(--zinc-950);
}

::-webkit-scrollbar-thumb {
    background: var(--zinc-800);
    border: 3px solid var(--zinc-950);
    border-radius: 12px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--zinc-700);
}

/* Selection */
::selection {
    background: var(--clinical-emerald);
    color: #000;
}

/* Monospace Data Points */
.data-mono {
    font-family: 'JetBrains Mono', monospace;
    font-variant-numeric: tabular-nums;
}

/* Button & Card Animations */
button, a {
    cursor: pointer;
}

.active-pulse {
    position: relative;
}

.active-pulse::before {
    content: '';
    position: absolute;
    inset: -4px;
    border: 1px solid var(--blue-500);
    border-radius: inherit;
    opacity: 0;
    animation: pulse-ring 2s infinite;
}

@keyframes pulse-ring {
    0% { transform: scale(0.95); opacity: 0.8; }
    50% { transform: scale(1.05); opacity: 0; }
    100% { transform: scale(0.95); opacity: 0; }
}

/* Premium Divider */
.premium-divider {
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--glass-border), transparent);
    width: 100%;
    margin: 2rem 0;
}

/* Responsive Fixes */
@media (max-width: 768px) {
    .nav-pill {
        border-radius: 32px;
        padding: 0.5rem 1rem;
    }
    
    h1 {
        font-size: 4rem !important;
    }
    
    .view-section {
        padding-top: 2rem;
    }
    
    .modal-content {
        margin: 1rem;
        max-height: 90vh;
    }
}

/* Tab Active State */
.tab-btn.active {
    background: #fff;
    color: #000;
    border-color: #fff;
    transform: scale(1.05);
}