:root {
    --primary: #6366f1; /* Indigo */
    --primary-hover: #4f46e5;
    --bg-dark: #0f172a; /* Slate 900 */
    --card-bg: rgba(30, 41, 59, 0.7); /* Glassmorphism base */
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border-color: rgba(255, 255, 255, 0.1);
    --font-main: 'Inter', system-ui, -apple-system, sans-serif;
}

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

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    font-family: var(--font-main);
    line-height: 1.5;
    overflow-x: hidden;
}

/* Glassmorphism Sidebar */
.sidebar {
    width: 260px;
    height: 100vh;
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    border-right: 1px solid var(--border-color);
    position: fixed;
    padding: 2rem 1rem;
    transition: all 0.3s ease;
}

.main-content {
    margin-left: 260px;
    padding: 2rem;
    min-height: 100vh;
}

h1, h2, h3 {
    margin-bottom: 1.5rem;
    font-weight: 700;
}

.card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    padding: 1.5rem;
    margin-bottom: 1rem;
    transition: transform 0.2s ease, border-color 0.2s ease;
}

.card:hover {
    transform: translateY(-2px);
    border-color: var(--primary);
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: var(--primary-hover);
}

.nav-link {
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    border-radius: 0.5rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.nav-link.active, .nav-link:hover {
    background-color: rgba(99, 102, 241, 0.1);
    color: var(--primary);
}