/**
 * App.css - Global Base Styles
 * 
 * Reset, typography, and CSS variables.
 */

/* ================================
   CSS VARIABLES
   ================================ */
:root {
    /* Colors */
    --color-primary: #3b82f6;
    --color-primary-dark: #2563eb;
    --color-primary-light: #60a5fa;
    --color-secondary: #64748b;
    --color-success: #22c55e;
    --color-warning: #f59e0b;
    --color-danger: #ef4444;
    --color-info: #06b6d4;

    /* Neutrals */
    --color-dark: #1e293b;
    --color-gray-900: #0f172a;
    --color-gray-800: #1e293b;
    --color-gray-700: #334155;
    --color-gray-600: #475569;
    --color-gray-500: #64748b;
    --color-gray-400: #94a3b8;
    --color-gray-300: #cbd5e1;
    --color-gray-200: #e2e8f0;
    --color-gray-100: #f1f5f9;
    --color-gray-50: #f8fafc;
    --color-white: #ffffff;

    /* Typography */
    --font-sans: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: ui-monospace, SFMono-Regular, 'SF Mono', Menlo, monospace;
    --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;

    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-2xl: 48px;

    /* Border radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);

    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.2s ease;
    --transition-slow: 0.3s ease;

    /* Z-index layers */
    --z-dropdown: 100;
    --z-sticky: 200;
    --z-modal-backdrop: 900;
    --z-modal: 1000;
    --z-tooltip: 1100;
    --z-toast: 1200;
}

/* ================================
   CSS RESET
   ================================ */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    font-size: var(--font-size-base);
    line-height: 1.5;
    color: var(--color-gray-800);
    background-color: var(--color-gray-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ================================
   TYPOGRAPHY
   ================================ */
h1,
h2,
h3,
h4,
h5,
h6 {
    font-weight: 600;
    line-height: 1.25;
    color: var(--color-gray-900);
}

h1 {
    font-size: var(--font-size-3xl);
}

h2 {
    font-size: var(--font-size-2xl);
}

h3 {
    font-size: var(--font-size-xl);
}

h4 {
    font-size: var(--font-size-lg);
}

h5 {
    font-size: var(--font-size-base);
}

h6 {
    font-size: var(--font-size-sm);
}

p {
    margin-bottom: var(--spacing-md);
}

a {
    color: var(--color-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--color-primary-dark);
    text-decoration: underline;
}

strong,
b {
    font-weight: 600;
}

small {
    font-size: var(--font-size-sm);
}

code {
    font-family: var(--font-mono);
    font-size: 0.875em;
    padding: 2px 6px;
    background: var(--color-gray-100);
    border-radius: var(--radius-sm);
}

pre {
    font-family: var(--font-mono);
    font-size: var(--font-size-sm);
    padding: var(--spacing-md);
    background: var(--color-gray-900);
    color: var(--color-gray-100);
    border-radius: var(--radius-md);
    overflow-x: auto;
}

/* ================================
   IMAGES & MEDIA
   ================================ */
img,
video {
    max-width: 100%;
    height: auto;
    display: block;
}

/* ================================
   LISTS
   ================================ */
ul,
ol {
    padding-left: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

li {
    margin-bottom: var(--spacing-xs);
}

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

/* Container */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.container-fluid {
    width: 100%;
    padding: 0 var(--spacing-md);
}

/* Display */
.d-none {
    display: none !important;
}

.d-block {
    display: block !important;
}

.d-flex {
    display: flex !important;
}

.d-inline-flex {
    display: inline-flex !important;
}

.d-grid {
    display: grid !important;
}

/* Flexbox */
.flex-row {
    flex-direction: row;
}

.flex-column {
    flex-direction: column;
}

.flex-wrap {
    flex-wrap: wrap;
}

.flex-nowrap {
    flex-wrap: nowrap;
}

.flex-1 {
    flex: 1;
}

.flex-shrink-0 {
    flex-shrink: 0;
}

.justify-start {
    justify-content: flex-start;
}

.justify-center {
    justify-content: center;
}

.justify-end {
    justify-content: flex-end;
}

.justify-between {
    justify-content: space-between;
}

.justify-around {
    justify-content: space-around;
}

.items-start {
    align-items: flex-start;
}

.items-center {
    align-items: center;
}

.items-end {
    align-items: flex-end;
}

.items-stretch {
    align-items: stretch;
}

.gap-1 {
    gap: var(--spacing-xs);
}

.gap-2 {
    gap: var(--spacing-sm);
}

.gap-3 {
    gap: var(--spacing-md);
}

.gap-4 {
    gap: var(--spacing-lg);
}

.gap-5 {
    gap: var(--spacing-xl);
}

/* Text alignment */
.text-left {
    text-align: left;
}

.text-center {
    text-align: center;
}

.text-right {
    text-align: right;
}

/* Text colors */
.text-muted {
    color: var(--color-gray-500);
}

.text-primary {
    color: var(--color-primary);
}

.text-success {
    color: var(--color-success);
}

.text-warning {
    color: var(--color-warning);
}

.text-danger {
    color: var(--color-danger);
}

/* Font weight */
.font-normal {
    font-weight: 400;
}

.font-medium {
    font-weight: 500;
}

.font-semibold {
    font-weight: 600;
}

.font-bold {
    font-weight: 700;
}

/* Spacing utilities */
.m-0 {
    margin: 0;
}

.m-auto {
    margin: auto;
}

.mt-0 {
    margin-top: 0;
}

.mt-1 {
    margin-top: var(--spacing-xs);
}

.mt-2 {
    margin-top: var(--spacing-sm);
}

.mt-3 {
    margin-top: var(--spacing-md);
}

.mt-4 {
    margin-top: var(--spacing-lg);
}

.mt-5 {
    margin-top: var(--spacing-xl);
}

.mb-0 {
    margin-bottom: 0;
}

.mb-1 {
    margin-bottom: var(--spacing-xs);
}

.mb-2 {
    margin-bottom: var(--spacing-sm);
}

.mb-3 {
    margin-bottom: var(--spacing-md);
}

.mb-4 {
    margin-bottom: var(--spacing-lg);
}

.mb-5 {
    margin-bottom: var(--spacing-xl);
}

.p-0 {
    padding: 0;
}

.p-1 {
    padding: var(--spacing-xs);
}

.p-2 {
    padding: var(--spacing-sm);
}

.p-3 {
    padding: var(--spacing-md);
}

.p-4 {
    padding: var(--spacing-lg);
}

.p-5 {
    padding: var(--spacing-xl);
}

/* Width utilities */
.w-full {
    width: 100%;
}

.w-auto {
    width: auto;
}

/* Visibility */
.invisible {
    visibility: hidden;
}

.visible {
    visibility: visible;
}

/* Overflow */
.overflow-hidden {
    overflow: hidden;
}

.overflow-auto {
    overflow: auto;
}

.overflow-scroll {
    overflow: scroll;
}

/* Cursor */
.cursor-pointer {
    cursor: pointer;
}

.cursor-not-allowed {
    cursor: not-allowed;
}

/* Selection */
.select-none {
    user-select: none;
}

.select-all {
    user-select: all;
}

/* ================================
   AJAX LOADING OVERLAY
   ================================ */
.ajax-loading {
    position: relative;
    pointer-events: none;
}

.ajax-loading::before {
    content: '';
    position: absolute;
    inset: 0;
    background: rgba(255, 255, 255, 0.7);
    z-index: 10;
    border-radius: inherit;
}

.ajax-loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 32px;
    height: 32px;
    margin: -16px 0 0 -16px;
    border: 3px solid var(--color-gray-200);
    border-top-color: var(--color-primary);
    border-radius: 50%;
    z-index: 11;
    animation: ajax-spin 0.8s linear infinite;
}

@keyframes ajax-spin {
    to {
        transform: rotate(360deg);
    }
}