/**
 * AI Academy Design System
 * Centrale definitie van alle design tokens voor consistente styling.
 */

:root {
    /* ===== COLORS ===== */

    /* Primary palette */
    --color-primary-50: #eef2ff;
    --color-primary-100: #e0e7ff;
    --color-primary-200: #c7d2fe;
    --color-primary-300: #a5b4fc;
    --color-primary-400: #818cf8;
    --color-primary-500: #667eea;
    --color-primary-600: #4f46e5;
    --color-primary-700: #4338ca;
    --color-primary-800: #3730a3;
    --color-primary-900: #312e81;

    /* Secondary palette (purple gradient end) */
    --color-secondary-500: #764ba2;
    --color-secondary-600: #6b3fa0;
    --color-secondary-700: #5a2d91;

    /* Neutral palette */
    --color-neutral-50: #f8fafc;
    --color-neutral-100: #f1f5f9;
    --color-neutral-200: #e2e8f0;
    --color-neutral-300: #cbd5e1;
    --color-neutral-400: #94a3b8;
    --color-neutral-500: #64748b;
    --color-neutral-600: #475569;
    --color-neutral-700: #334155;
    --color-neutral-800: #1e293b;
    --color-neutral-900: #0f172a;

    /* Semantic colors */
    --color-success-50: #f0fdf4;
    --color-success-500: #22c55e;
    --color-success-600: #16a34a;
    --color-success-700: #15803d;

    --color-warning-50: #fffbeb;
    --color-warning-500: #f59e0b;
    --color-warning-600: #d97706;

    --color-error-50: #fef2f2;
    --color-error-500: #ef4444;
    --color-error-600: #dc2626;
    --color-error-700: #b91c1c;

    --color-info-50: #eff6ff;
    --color-info-500: #3b82f6;
    --color-info-600: #2563eb;

    /* Legacy brand colors (for backwards compatibility) */
    --brand-primary: var(--color-primary-500);
    --brand-secondary: var(--color-neutral-900);
    --brand-accent: var(--color-success-600);
    --brand-muted: var(--color-neutral-500);
    --brand-surface: var(--color-neutral-50);

    /* ===== TYPOGRAPHY ===== */

    --font-family-base: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-family-display: 'Playfair Display', Georgia, serif;
    --font-family-mono: 'Fira Code', 'Courier New', monospace;

    /* Font sizes */
    --text-xs: 0.75rem;      /* 12px */
    --text-sm: 0.875rem;     /* 14px */
    --text-base: 1rem;       /* 16px */
    --text-lg: 1.125rem;     /* 18px */
    --text-xl: 1.25rem;      /* 20px */
    --text-2xl: 1.5rem;      /* 24px */
    --text-3xl: 1.875rem;    /* 30px */
    --text-4xl: 2.25rem;     /* 36px */
    --text-5xl: 3rem;        /* 48px */

    /* Font weights */
    --font-normal: 400;
    --font-medium: 500;
    --font-semibold: 600;
    --font-bold: 700;

    /* Line heights */
    --leading-tight: 1.25;
    --leading-normal: 1.5;
    --leading-relaxed: 1.75;

    /* ===== SPACING ===== */

    --space-1: 0.25rem;      /* 4px */
    --space-2: 0.5rem;       /* 8px */
    --space-3: 0.75rem;      /* 12px */
    --space-4: 1rem;         /* 16px */
    --space-5: 1.25rem;      /* 20px */
    --space-6: 1.5rem;       /* 24px */
    --space-8: 2rem;         /* 32px */
    --space-10: 2.5rem;      /* 40px */
    --space-12: 3rem;        /* 48px */
    --space-16: 4rem;        /* 64px */
    --space-20: 5rem;        /* 80px */

    /* ===== BORDERS ===== */

    --radius-sm: 0.25rem;    /* 4px */
    --radius-md: 0.5rem;     /* 8px */
    --radius-lg: 0.75rem;    /* 12px */
    --radius-xl: 1rem;       /* 16px */
    --radius-2xl: 1.5rem;    /* 24px */
    --radius-full: 9999px;

    --border-width: 1px;
    --border-color: var(--color-neutral-200);

    /* ===== SHADOWS ===== */

    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --shadow-2xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);

    /* ===== TRANSITIONS ===== */

    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 350ms ease;

    /* ===== Z-INDEX ===== */

    --z-dropdown: 1000;
    --z-sticky: 1020;
    --z-fixed: 1030;
    --z-modal-backdrop: 1040;
    --z-modal: 1050;
    --z-popover: 1060;
    --z-tooltip: 1070;
    --z-toast: 1080;

    /* ===== GRADIENTS ===== */

    --gradient-primary: linear-gradient(135deg, var(--color-primary-500) 0%, var(--color-secondary-500) 100%);
    --gradient-hero: linear-gradient(135deg, var(--color-primary-500) 0%, var(--color-secondary-500) 100%);
    --gradient-card: linear-gradient(145deg, #ffffff 0%, var(--color-neutral-50) 100%);
}

/* ===== UTILITY CLASSES ===== */

/* Text colors */
.text-primary { color: var(--color-primary-500); }
.text-secondary { color: var(--color-neutral-600); }
.text-muted { color: var(--color-neutral-500); }
.text-success { color: var(--color-success-600); }
.text-warning { color: var(--color-warning-600); }
.text-error { color: var(--color-error-600); }

/* Background colors */
.bg-primary { background-color: var(--color-primary-500); }
.bg-primary-subtle { background-color: var(--color-primary-50); }
.bg-surface { background-color: var(--color-neutral-50); }
.bg-success-subtle { background-color: var(--color-success-50); }
.bg-warning-subtle { background-color: var(--color-warning-50); }
.bg-error-subtle { background-color: var(--color-error-50); }

/* Gradient backgrounds */
.bg-gradient-primary {
    background: var(--gradient-primary);
}

.bg-gradient-hero {
    background: var(--gradient-hero);
}

/* Shadows */
.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-xl { box-shadow: var(--shadow-xl); }

/* Border radius */
.rounded-sm { border-radius: var(--radius-sm); }
.rounded-md { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }
.rounded-full { border-radius: var(--radius-full); }

/* Transitions */
.transition-fast { transition: all var(--transition-fast); }
.transition-normal { transition: all var(--transition-normal); }
.transition-slow { transition: all var(--transition-slow); }

/* ===== COMPONENT BASE STYLES ===== */

/* Cards */
.card-modern {
    background: var(--gradient-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--color-neutral-100);
    transition: all var(--transition-normal);
}

.card-modern:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

/* Buttons */
.btn-modern {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    font-weight: var(--font-semibold);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    cursor: pointer;
    border: none;
}

.btn-modern-primary {
    background: var(--gradient-primary);
    color: white;
}

.btn-modern-primary:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

.btn-modern-outline {
    background: transparent;
    border: 2px solid var(--color-primary-500);
    color: var(--color-primary-500);
}

.btn-modern-outline:hover {
    background: var(--color-primary-50);
}

/* Form inputs */
.input-modern {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    border: 1px solid var(--color-neutral-300);
    border-radius: var(--radius-md);
    font-size: var(--text-base);
    transition: all var(--transition-fast);
}

.input-modern:focus {
    outline: none;
    border-color: var(--color-primary-500);
    box-shadow: 0 0 0 3px var(--color-primary-100);
}

/* Badges */
.badge-modern {
    display: inline-flex;
    align-items: center;
    padding: var(--space-1) var(--space-3);
    font-size: var(--text-xs);
    font-weight: var(--font-medium);
    border-radius: var(--radius-full);
}

.badge-modern-primary {
    background: var(--color-primary-100);
    color: var(--color-primary-700);
}

.badge-modern-success {
    background: var(--color-success-50);
    color: var(--color-success-700);
}

.badge-modern-warning {
    background: var(--color-warning-50);
    color: var(--color-warning-600);
}

.badge-modern-error {
    background: var(--color-error-50);
    color: var(--color-error-700);
}

/* ===== RESPONSIVE BREAKPOINTS ===== */

@media (max-width: 639px) {
    :root {
        --text-4xl: 1.875rem;
        --text-5xl: 2.25rem;
    }
}

@media (min-width: 640px) {
    /* sm breakpoint styles */
}

@media (min-width: 768px) {
    /* md breakpoint styles */
}

@media (min-width: 1024px) {
    /* lg breakpoint styles */
}

@media (min-width: 1280px) {
    /* xl breakpoint styles */
}