/**
 * Filename: css/variables.css
 * Author: Academic Network
 * Version: 1.0.0
 * Description: CSS custom properties (variables) for theming and consistent styling
 * Last Modified: 2025-10-27
 *
 * Note: Primary colors are set via JavaScript after loading config from backend
 * This ensures university-specific branding is applied dynamically
 */

:root {
    /* ============================================
     * PRIMARY BRANDING COLORS
     * These will be set dynamically from config
     * ============================================ */
    --color-primary: #086586;
    --color-secondary: #0a7a9f;
    --color-accent: #0d98c7;

    /* Primary color variations (auto-generated by JS) */
    --color-primary-light: #0a9bc7;
    --color-primary-lighter: #d4f1f9;
    --color-primary-dark: #064d63;
    --color-primary-darker: #043a4a;

    /* Hover states */
    --color-primary-hover: #0a7a9f;
    --color-secondary-hover: #0d98c7;

    /* ============================================
     * SEMANTIC COLORS
     * ============================================ */
    --color-success: #28a745;
    --color-success-light: #d4edda;
    --color-success-dark: #1e7e34;

    --color-warning: #ffc107;
    --color-warning-light: #fff3cd;
    --color-warning-dark: #e0a800;

    --color-danger: #dc3545;
    --color-danger-light: #f8d7da;
    --color-danger-dark: #bd2130;

    --color-info: #17a2b8;
    --color-info-light: #d1ecf1;
    --color-info-dark: #117a8b;

    /* ============================================
     * NEUTRAL COLORS
     * ============================================ */
    --color-white: #ffffff;
    --color-black: #000000;

    --color-gray-100: #f8f9fa;
    --color-gray-200: #e9ecef;
    --color-gray-300: #dee2e6;
    --color-gray-400: #ced4da;
    --color-gray-500: #adb5bd;
    --color-gray-600: #6c757d;
    --color-gray-700: #495057;
    --color-gray-800: #343a40;
    --color-gray-900: #212529;

    /* ============================================
     * BACKGROUND COLORS
     * ============================================ */
    --bg-primary: var(--color-white);
    --bg-secondary: var(--color-gray-100);
    --bg-tertiary: var(--color-gray-200);
    --bg-dark: var(--color-gray-900);
    --bg-light: var(--color-gray-100);

    /* Overlay backgrounds */
    --bg-overlay: rgba(0, 0, 0, 0.5);
    --bg-overlay-light: rgba(0, 0, 0, 0.3);
    --bg-overlay-dark: rgba(0, 0, 0, 0.7);

    /* ============================================
     * TEXT COLORS
     * ============================================ */
    --text-primary: var(--color-gray-900);
    --text-secondary: var(--color-gray-600);
    --text-muted: var(--color-gray-500);
    --text-light: var(--color-gray-400);
    --text-white: var(--color-white);
    --text-link: var(--color-primary);
    --text-link-hover: var(--color-primary-dark);

    /* ============================================
     * BORDER COLORS
     * ============================================ */
    --border-color: var(--color-gray-300);
    --border-color-light: var(--color-gray-200);
    --border-color-dark: var(--color-gray-400);

    /* ============================================
     * SPACING SYSTEM
     * 8px base unit
     * ============================================ */
    --spacing-xs: 0.25rem;    /* 4px */
    --spacing-sm: 0.5rem;     /* 8px */
    --spacing-md: 1rem;       /* 16px */
    --spacing-lg: 1.5rem;     /* 24px */
    --spacing-xl: 2rem;       /* 32px */
    --spacing-2xl: 3rem;      /* 48px */
    --spacing-3xl: 4rem;      /* 64px */
    --spacing-4xl: 6rem;      /* 96px */

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

    /* Font Families */
    --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
    sans-serif;
    --font-mono: 'SFMono-Regular', 'Consolas', 'Liberation Mono', 'Menlo', 'Courier', monospace;

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

    /* Font Weights */
    --font-weight-light: 300;
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    --font-weight-extrabold: 800;

    /* Line Heights */
    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;
    --line-height-loose: 2;

    /* Letter Spacing */
    --letter-spacing-tight: -0.025em;
    --letter-spacing-normal: 0;
    --letter-spacing-wide: 0.025em;
    --letter-spacing-wider: 0.05em;

    /* ============================================
     * BORDER RADIUS
     * ============================================ */
    --radius-none: 0;
    --radius-sm: 0.25rem;     /* 4px */
    --radius-md: 0.375rem;    /* 6px */
    --radius-lg: 0.5rem;      /* 8px */
    --radius-xl: 0.75rem;     /* 12px */
    --radius-2xl: 1rem;       /* 16px */
    --radius-full: 9999px;    /* Fully rounded */

    /* ============================================
     * SHADOWS
     * ============================================ */
    --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --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);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    --shadow-inner: inset 0 2px 4px 0 rgba(0, 0, 0, 0.06);

    /* Colored shadows for primary actions */
    --shadow-primary: 0 4px 14px 0 rgba(8, 101, 134, 0.39);
    --shadow-success: 0 4px 14px 0 rgba(40, 167, 69, 0.39);
    --shadow-danger: 0 4px 14px 0 rgba(220, 53, 69, 0.39);

    /* ============================================
     * Z-INDEX LAYERS
     * ============================================ */
    --z-index-dropdown: 1000;
    --z-index-sticky: 1020;
    --z-index-fixed: 1030;
    --z-index-modal-backdrop: 1040;
    --z-index-modal: 1050;
    --z-index-popover: 1060;
    --z-index-tooltip: 1070;

    /* ============================================
     * TRANSITIONS
     * ============================================ */
    --transition-speed-fast: 150ms;
    --transition-speed-normal: 300ms;
    --transition-speed-slow: 500ms;

    --transition-timing: cubic-bezier(0.4, 0, 0.2, 1);
    --transition-timing-ease-in: cubic-bezier(0.4, 0, 1, 1);
    --transition-timing-ease-out: cubic-bezier(0, 0, 0.2, 1);
    --transition-timing-ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);

    /* Common transitions */
    --transition-all: all var(--transition-speed-normal) var(--transition-timing);
    --transition-colors: color var(--transition-speed-normal) var(--transition-timing),
    background-color var(--transition-speed-normal) var(--transition-timing),
    border-color var(--transition-speed-normal) var(--transition-timing);
    --transition-transform: transform var(--transition-speed-normal) var(--transition-timing);
    --transition-opacity: opacity var(--transition-speed-normal) var(--transition-timing);

    /* ============================================
     * COMPONENT-SPECIFIC VARIABLES
     * ============================================ */

    /* Buttons */
    --btn-padding-y: 0.5rem;
    --btn-padding-x: 1rem;
    --btn-padding-y-sm: 0.375rem;
    --btn-padding-x-sm: 0.75rem;
    --btn-padding-y-lg: 0.75rem;
    --btn-padding-x-lg: 1.5rem;
    --btn-border-radius: var(--radius-md);
    --btn-font-weight: var(--font-weight-medium);

    /* Inputs */
    --input-padding-y: 0.5rem;
    --input-padding-x: 0.75rem;
    --input-height: 2.5rem;
    --input-border-width: 1px;
    --input-border-radius: var(--radius-md);
    --input-bg: var(--color-white);
    --input-border-color: var(--border-color);
    --input-focus-border-color: var(--color-primary);
    --input-focus-shadow: 0 0 0 3px rgba(8, 101, 134, 0.1);

    /* Cards */
    --card-padding: var(--spacing-lg);
    --card-border-radius: var(--radius-lg);
    --card-bg: var(--color-white);
    --card-border: 1px solid var(--border-color);
    --card-shadow: var(--shadow-sm);
    --card-shadow-hover: var(--shadow-md);

    /* Modals */
    --modal-padding: var(--spacing-xl);
    --modal-border-radius: var(--radius-xl);
    --modal-max-width: 600px;
    --modal-backdrop-bg: var(--bg-overlay);

    /* Navigation */
    --nav-height: 70px;
    --sidebar-width: 280px;
    --sidebar-collapsed-width: 80px;

    /* Progress bars */
    --progress-height: 8px;
    --progress-bg: var(--color-gray-200);
    --progress-border-radius: var(--radius-full);

    /* Badges */
    --badge-padding-y: 0.25rem;
    --badge-padding-x: 0.5rem;
    --badge-border-radius: var(--radius-md);
    --badge-font-size: var(--font-size-xs);
    --badge-font-weight: var(--font-weight-semibold);

    /* ============================================
     * BREAKPOINTS
     * ============================================ */
    --breakpoint-xs: 0;
    --breakpoint-sm: 576px;
    --breakpoint-md: 768px;
    --breakpoint-lg: 992px;
    --breakpoint-xl: 1200px;
    --breakpoint-2xl: 1400px;

    /* ============================================
     * CONTAINER WIDTHS
     * ============================================ */
    --container-sm: 540px;
    --container-md: 720px;
    --container-lg: 960px;
    --container-xl: 1140px;
    --container-2xl: 1320px;

    /* ============================================
     * GRID SYSTEM
     * ============================================ */
    --grid-columns: 12;
    --grid-gutter-width: var(--spacing-lg);

    /* ============================================
     * FILE UPLOAD SPECIFIC
     * ============================================ */
    --upload-zone-bg: var(--color-gray-100);
    --upload-zone-border: 2px dashed var(--border-color);
    --upload-zone-border-active: 2px dashed var(--color-primary);
    --upload-zone-padding: var(--spacing-2xl);
    --upload-zone-border-radius: var(--radius-lg);

    /* ============================================
     * DIMENSION CARDS
     * ============================================ */
    --dimension-card-height: 180px;
    --dimension-icon-size: 3rem;

    /* ============================================
     * STATUS INDICATORS
     * ============================================ */
    --status-pending: var(--color-warning);
    --status-in-progress: var(--color-info);
    --status-completed: var(--color-success);
    --status-error: var(--color-danger);

    /* ============================================
     * LOADING ANIMATIONS
     * ============================================ */
    --loader-size: 40px;
    --loader-border-width: 4px;
    --loader-color: var(--color-primary);
}

/* ============================================
 * DARK MODE VARIABLES
 * (Future enhancement - currently disabled)
 * ============================================ */
@media (prefers-color-scheme: dark) {
    :root[data-theme="dark"] {
        /* Dark mode colors will be defined here when feature is enabled */
        /* --color-primary: #0a9bc7; */
        /* --bg-primary: var(--color-gray-900); */
        /* --text-primary: var(--color-gray-100); */
    }
}

/* ============================================
 * REDUCED MOTION
 * Respect user's motion preferences
 * ============================================ */
@media (prefers-reduced-motion: reduce) {
    :root {
        --transition-speed-fast: 0ms;
        --transition-speed-normal: 0ms;
        --transition-speed-slow: 0ms;
    }

    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* ============================================
 * PRINT STYLES VARIABLES
 * ============================================ */
@media print {
    :root {
        --color-primary: #000000;
        --text-primary: #000000;
        --bg-primary: #ffffff;
    }
}

/* ============================================
 * HIGH CONTRAST MODE
 * For accessibility
 * ============================================ */
@media (prefers-contrast: high) {
    :root {
        --border-color: var(--color-gray-900);
        --text-secondary: var(--color-gray-900);
    }
}

/* ============================================
 * UTILITY CLASSES USING VARIABLES
 * ============================================ */

/* Spacing utilities will use these variables */
.m-0 { margin: 0; }
.m-xs { margin: var(--spacing-xs); }
.m-sm { margin: var(--spacing-sm); }
.m-md { margin: var(--spacing-md); }
.m-lg { margin: var(--spacing-lg); }
.m-xl { margin: var(--spacing-xl); }

.p-0 { padding: 0; }
.p-xs { padding: var(--spacing-xs); }
.p-sm { padding: var(--spacing-sm); }
.p-md { padding: var(--spacing-md); }
.p-lg { padding: var(--spacing-lg); }
.p-xl { padding: var(--spacing-xl); }

/* Text utilities */
.text-primary { color: var(--text-primary); }
.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }
.text-white { color: var(--text-white); }

/* Background utilities */
.bg-primary { background-color: var(--color-primary); }
.bg-secondary { background-color: var(--bg-secondary); }
.bg-white { background-color: var(--color-white); }
.bg-light { background-color: var(--bg-light); }
.bg-dark { background-color: var(--bg-dark); }

/* Border utilities */
.border { border: 1px solid var(--border-color); }
.border-top { border-top: 1px solid var(--border-color); }
.border-bottom { border-bottom: 1px solid var(--border-color); }
.border-left { border-left: 1px solid var(--border-color); }
.border-right { border-right: 1px solid var(--border-color); }

/* Rounded corners */
.rounded-none { border-radius: var(--radius-none); }
.rounded-sm { border-radius: var(--radius-sm); }
.rounded { 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); }

/* Shadows */
.shadow-none { box-shadow: none; }
.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-xl { box-shadow: var(--shadow-xl); }