/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #8b5cf6;
    --accent-color: #06b6d4;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;

    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --bg-card: #1e293b;

    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;

    --border-color: #334155;
    --border-light: #475569;

    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 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, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);

    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
}

html, body {
    margin: 0;
    padding: 0;
    height: 100vh;
    overflow: hidden;
    box-sizing: border-box;
}

body {
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    color: var(--text-primary);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 14px;
    line-height: 1.6;
}

/* App Container */
.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
}

/* Header */
.header {
    background: rgba(30, 41, 59, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 2rem;
    position: sticky;
    top: 0;
    z-index: 100;
}

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

a.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

a.logo:hover {
    text-decoration: none;
}

.logo i {
    font-size: 2rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header-controls {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

.btn-primary:active {
    transform: translateY(0);
}

/* Main Content */
.main-content {
    display: flex;
    flex: 1;
    justify-content: center;
    align-items: center;
    padding: 0;
    width: 100%;
    height: calc(100vh - 4rem - 4rem); /* Subtract header and footer heights */
}

/* Canvas Container */
.canvas-container {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
    height: 100%;
    min-height: 100%;
}

#glCanvas {
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    background: var(--bg-primary);
    width: 100%;
    height: 100%;
}

/* Footer */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 1.5rem 2rem;
    margin-top: auto;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1400px;
    margin: 0 auto;
    color: var(--text-muted);
    font-size: 0.875rem;
}

.footer-links {
    display: flex;
    gap: 1.5rem;
}

.footer-link {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.2s ease;
}

.footer-link:hover {
    color: var(--primary-color);
}

/* Responsive Design */
@media (max-width: 768px) {
    .header {
        padding: 1rem;
    }

    .main-content {
        padding: 0;
    }

    .footer-content {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }

    .logo {
        font-size: 1.25rem;
    }

    .logo i {
        font-size: 1.5rem;
    }

    #glCanvas {
        width: 100%;
        height: 100%;
    }
}