:root {
    --bg-color: #050505;
    --card-bg: rgba(20, 20, 20, 0.6);
    --accent-blue: #00f2ff;
    --accent-green: #39ff14;
    --accent-crimson: #ff003c;
    --text-primary: #ffffff;
    --text-secondary: #aaaaaa;
    --glass-border: rgba(255, 255, 255, 0.1);
    --pulse-rising: #39ff14;
    --pulse-falling: #555555;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    overflow-x: hidden;
    min-height: 100vh;
}

/* Header & Ticker */
.app-header {
    display: flex;
    align-items: center;
    padding: 1rem 2rem;
    border-bottom: 1px solid var(--glass-border);
    background: rgba(5, 5, 5, 0.8);
    backdrop-filter: blur(10px);
    position: sticky;
    top: 0;
    z-index: 100;
    gap: 2rem;
}

.logo-container {
    display: flex;
    align-items: center;
    gap: 0.8rem;
}

.logo-pulse {
    width: 24px;
    height: 24px;
    background: var(--accent-blue);
    border-radius: 50%;
    box-shadow: 0 0 15px var(--accent-blue);
    animation: pulse-logo 2s infinite cubic-bezier(0.4, 0, 0.6, 1);
}

@keyframes pulse-logo {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.5; transform: scale(0.8); }
}

.ticker-wrapper {
    flex-grow: 1;
    overflow: hidden;
    background: rgba(255, 255, 255, 0.03);
    border-radius: 20px;
    padding: 0.5rem 0;
}

.ticker {
    display: flex;
    white-space: nowrap;
    animation: marquee 30s linear infinite;
}

.ticker:hover {
    animation-play-state: paused;
}

.ticker-item {
    padding: 0 2rem;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
}

@keyframes marquee {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}

/* Category Nav */
.category-nav {
    display: flex;
    justify-content: center;
    gap: 1rem;
    padding: 2rem;
    flex-wrap: wrap;
}

.nav-item {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    color: var(--text-secondary);
    padding: 0.6rem 1.5rem;
    border-radius: 30px;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    font-weight: 600;
    font-size: 0.9rem;
}

.nav-item:hover, .nav-item.active {
    background: var(--text-primary);
    color: var(--bg-color);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(255, 255, 255, 0.1);
}

/* Featured Grid - Asymmetrical */
.discovery-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem 4rem;
}

.featured-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-auto-rows: 250px;
    gap: 1.5rem;
    margin-bottom: 4rem;
}

.trend-card {
    position: relative;
    border-radius: 24px;
    overflow: hidden;
    background: var(--card-bg);
    border: 1px solid var(--glass-border);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    cursor: pointer;
    box-shadow: 0 0 0 rgba(var(--accent-rgb), 0);
}

.trend-card:hover {
    border-color: var(--accent-color);
    box-shadow: 0 0 30px rgba(var(--accent-rgb), 0.15);
}

.sparkline-gradient stop:first-child { stop-color: var(--accent-color); }
.sparkline-gradient stop:last-child { stop-color: var(--accent-blue); }

.trend-card.large {
    grid-column: span 2;
    grid-row: span 2;
}

.trend-card img, .trend-card video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s ease;
}

.trend-card:hover img, .trend-card:hover video {
    transform: scale(1.05);
}

/* Glassmorphic Overlay */
.card-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 1.5rem;
    background: linear-gradient(transparent, rgba(0, 0, 0, 0.9));
    backdrop-filter: blur(0px);
    transition: all 0.4s ease;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    height: 100%;
}

.trend-card:hover .card-overlay {
    backdrop-filter: blur(12px);
    background: rgba(0, 0, 0, 0.6);
}

.card-content {
    transform: translateY(20px);
    transition: transform 0.4s ease;
}

.trend-card:hover .card-content {
    transform: translateY(0);
}

.category-tag {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 700;
    margin-bottom: 0.5rem;
    display: inline-block;
}

.trend-title {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    line-height: 1.2;
}

.large .trend-title {
    font-size: 2rem;
}

.engagement-stats {
    display: flex;
    gap: 1.5rem;
    font-size: 0.8rem;
    color: var(--text-secondary);
    opacity: 0;
    transition: opacity 0.3s 0.1s ease;
}

.trend-card:hover .engagement-stats {
    opacity: 1;
}

/* Pulse Lines / Sparklines */
.pulse-line-container {
    height: 30px;
    margin-top: 1rem;
    position: relative;
}

.sparkline {
    width: 100%;
    height: 100%;
    stroke-width: 2;
    fill: none;
    stroke-dasharray: 200;
    stroke-dashoffset: 200;
}

.trend-card:hover .sparkline {
    animation: draw-sparkline 1.5s forwards ease-out;
}

@keyframes draw-sparkline {
    to { stroke-dashoffset: 0; }
}

/* Momentum Feed */
.trending-feed h2 {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    font-weight: 800;
    display: flex;
    align-items: center;
    gap: 10px;
}

.trending-feed h2::before {
    content: '';
    width: 8px;
    height: 8px;
    background: var(--accent-green);
    border-radius: 50%;
    box-shadow: 0 0 10px var(--accent-green);
}

.feed-container {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.feed-item {
    display: flex;
    align-items: center;
    padding: 1.2rem;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    gap: 1.5rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.feed-item:hover {
    background: rgba(255, 255, 255, 0.08);
    transform: translateX(10px);
    border-color: rgba(255, 255, 255, 0.2);
}

.feed-rank {
    font-size: 1.5rem;
    font-weight: 800;
    color: rgba(255, 255, 255, 0.1);
    min-width: 40px;
}

.feed-thumb {
    width: 60px;
    height: 60px;
    border-radius: 12px;
    overflow: hidden;
}

.feed-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.feed-info {
    flex-grow: 1;
}

.feed-title {
    font-weight: 600;
    font-size: 1rem;
}

.feed-meta {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.velocity-indicator {
    padding: 4px 8px;
    border-radius: 6px;
    font-size: 0.7rem;
    font-weight: 700;
}

.velocity-indicator.hot {
    background: rgba(255, 0, 60, 0.2);
    color: var(--accent-crimson);
    animation: hot-pulse 1s infinite;
}

@keyframes hot-pulse {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.1); opacity: 0.8; }
}

/* Skeleton Shimmer */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--bg-color);
    z-index: 1000;
    padding: 100px 2rem;
    display: block; /* Shown by default */
    transition: opacity 0.5s ease;
}

.shimmer-container {
    max-width: 1400px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-auto-rows: 250px;
    gap: 1.5rem;
}

.shimmer-box {
    background: linear-gradient(90deg, #111 25%, #222 50%, #111 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    border-radius: 24px;
}

.featured-large { grid-column: span 2; grid-row: span 2; }

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

/* Performance Stats */
.performance-stats {
    font-size: 0.7rem;
    font-family: monospace;
    color: var(--accent-green);
    opacity: 0.7;
}

/* Staggered Animations */
.stagger-in {
    opacity: 0;
    transform: translateY(30px);
}

.animate-in {
    animation: slide-up 0.6s forwards cubic-bezier(0.23, 1, 0.32, 1);
}

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

@media (max-width: 1024px) {
    .featured-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 640px) {
    .featured-grid {
        grid-template-columns: 1fr;
    }
    .trend-card.large {
        grid-column: span 1;
        grid-row: span 1;
    }
    .app-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    .ticker-wrapper { width: 100%; }
}