/* ==========================================================================
   CSS Variables - Design Tokens
   ========================================================================== */

:root {
    /* Colors - Light Theme (original scheme) */
    --color-primary: #3d5afe;
    --color-primary-hover: #304ffe;
    --color-primary-light: #e8eaff;
    --color-accent: #ff4081;
    --color-accent-light: #ffe4ec;

    /* Neutrals */
    --color-bg: #f5f5f5;
    --color-bg-elevated: #ffffff;
    --color-bg-subtle: #eeeeee;
    --color-border: #e0e0e0;
    --color-border-strong: #bdbdbd;

    /* Text */
    --color-text: #212121;
    --color-text-secondary: #757575;
    --color-text-tertiary: #9e9e9e;
    --color-text-inverse: #ffffff;

    /* Semantic */
    --color-success: #4caf50;
    --color-warning: #ff9800;
    --color-error: #f44336;
    --color-info: #2196f3;

    /* Lesson Types */
    --color-lecture: #2196f3;
    --color-practice: #4caf50;
    --color-lab: #00bcd4;
    --color-seminar: #9c27b0;
    --color-consult: #e91e63;
    --color-exam: #f44336;
    --color-credit: #673ab7;
    --color-class: #ff9800;

    /* Shadows */
    --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
    --shadow-xl: 0 12px 32px rgba(0, 0, 0, 0.15);

    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;

    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;

    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.625;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;

    /* Z-index */
    --z-dropdown: 100;
    --z-sticky: 200;
    --z-modal: 1000;
    --z-toast: 1100;

    /* Layout */
    --container-max: 900px;
    --header-height: auto;
}

/* Dark Theme (original scheme) */
[data-theme="dark"] {
    --color-primary: #448aff;
    --color-primary-hover: #2979ff;
    --color-primary-light: #1a237e;
    --color-accent: #ff80ab;
    --color-accent-light: #4a1a2e;

    --color-bg: #121212;
    --color-bg-elevated: #1e1e1e;
    --color-bg-subtle: #2a2a2a;
    --color-border: #424242;
    --color-border-strong: #616161;

    --color-text: #e0e0e0;
    --color-text-secondary: #bdbdbd;
    --color-text-tertiary: #9e9e9e;

    --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.4);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 12px 32px rgba(0, 0, 0, 0.6);
}