:root {
    --bg-base: #0f172a;
    --bg-surface: #1e293b;
    --bg-panel: rgba(30, 41, 59, 0.7);
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --secondary: #8b5cf6;
    --accent: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border: rgba(255, 255, 255, 0.1);
    --glass-blur: blur(12px);
    --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -2px rgba(0, 0, 0, 0.25);
    --radius-md: 12px;
    --radius-lg: 20px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    background-color: var(--bg-base);
    color: var(--text-main);
    display: flex;
    height: 100vh;
    overflow: hidden;
    background-image: 
        radial-gradient(at 0% 0%, hsla(253,16%,7%,1) 0, transparent 50%), 
        radial-gradient(at 50% 0%, hsla(225,39%,30%,0.2) 0, transparent 50%), 
        radial-gradient(at 100% 0%, hsla(339,49%,30%,0.2) 0, transparent 50%);
}

/* Typography */
h1, h2, h3, h4 {
    font-weight: 700;
    letter-spacing: -0.02em;
}
h1 { font-size: 2.5rem; margin-bottom: 1rem; }
h2 { font-size: 1.75rem; margin-bottom: 0.75rem; }
p { line-height: 1.6; color: var(--text-muted); margin-bottom: 1rem; }

/* Layout Grid */
#app-container {
    display: grid;
    grid-template-columns: 280px 1fr 320px;
    width: 100%;
    height: 100%;
}

/* Glassmorphism Utilities */
.glass-panel {
    background: var(--bg-panel);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

/* Sidebar Navigation */
#sidebar {
    padding: 2rem 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
    border-right: 1px solid var(--border);
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: var(--glass-blur);
    z-index: 10;
}

.brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.nav-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
    padding-left: 0.75rem;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-muted);
    font-weight: 500;
    text-decoration: none;
}

.nav-item:hover, .nav-item.active {
    background: rgba(59, 130, 246, 0.1);
    color: var(--primary);
}

.nav-item.active {
    border-left: 3px solid var(--primary);
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

/* Main Content Area */
#main-content {
    padding: 2rem 3rem;
    overflow-y: auto;
    position: relative;
}

#main-content::-webkit-scrollbar {
    width: 6px;
}
#main-content::-webkit-scrollbar-thumb {
    background: var(--bg-surface);
    border-radius: 10px;
}

/* Right Metrics Panel */
#metrics-panel {
    padding: 2rem;
    border-left: 1px solid var(--border);
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: var(--glass-blur);
    overflow-y: auto;
}

.metric-card {
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.metric-value {
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-main);
}

.metric-title {
    font-size: 0.875rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* Progress Bar */
.progress-container {
    width: 100%;
    height: 8px;
    background: var(--bg-base);
    border-radius: 4px;
    overflow: hidden;
    margin-top: 0.5rem;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    border-radius: 4px;
    transition: width 1s ease-in-out;
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-md);
    border: none;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
}

.btn-primary {
    background: var(--primary);
    color: white;
    box-shadow: 0 4px 14px 0 rgba(59, 130, 246, 0.39);
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.4);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-main);
}
.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.15);
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.animate-fade-in {
    animation: fadeIn 0.4s ease-out forwards;
}

/* Print Styles */
@media print {
    body { background: white; color: black; display: block; overflow: visible; }
    #sidebar, #metrics-panel { display: none; }
    #main-content { padding: 0; }
    .glass-panel { border: none; box-shadow: none; }
    * { color: black !important; background: transparent !important; }
}

/* Responsive */
@media (max-width: 1200px) {
    #app-container { grid-template-columns: 250px 1fr; }
    #metrics-panel { display: none; }
}
@media (max-width: 768px) {
    #app-container { grid-template-columns: 1fr; }
    #sidebar { display: none; } /* Add hamburger menu logic later */
}