/**
 * =================================================================
 * EASYINSTALL DESIGN SYSTEM
 * Minimal, DevScan-inspired CSS framework
 * =================================================================
 *
 * Structure:
 * 1. CSS Variables (Light/Dark)
 * 2. Reset & Base
 * 3. Typography
 * 4. Layout (Container, Grid, Flex)
 * 5. Components (Buttons, Cards, Forms, Tables, Modals, Badges)
 * 6. Utilities
 *
 * VERSION: 1.0.0
 */

/* =================================================================
   1. CSS VARIABLES
   ================================================================= */

:root {
    /* Colors - Gray Scale (Zinc) */
    --gray-50: #fafafa;
    --gray-100: #f4f4f5;
    --gray-200: #e4e4e7;
    --gray-300: #d4d4d8;
    --gray-400: #a1a1aa;
    --gray-500: #71717a;
    --gray-600: #52525b;
    --gray-700: #3f3f46;
    --gray-800: #27272a;
    --gray-900: #18181b;
    --gray-950: #09090b;

    /* Semantic Colors */
    --accent: #3b82f6;
    --accent-hover: #2563eb;
    --success: #22c55e;
    --success-hover: #16a34a;
    --warning: #f59e0b;
    --warning-hover: #d97706;
    --danger: #ef4444;
    --danger-hover: #dc2626;

    /* Semantic Backgrounds */
    --bg-primary: #ffffff;
    --bg-secondary: var(--gray-50);
    --bg-tertiary: var(--gray-100);
    --bg-elevated: #ffffff;
    --bg-sidebar: var(--gray-900);
    --bg-input: #ffffff;
    --bg-hover: var(--gray-100);

    /* Text */
    --text-primary: var(--gray-900);
    --text-secondary: var(--gray-600);
    --text-muted: var(--gray-500);
    --text-inverse: #ffffff;

    /* Borders */
    --border-light: var(--gray-200);
    --border-default: var(--gray-300);

    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;

    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    --radius-xl: 12px;
    --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);

    /* Typography */
    --font-sans: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'SF Mono', monospace;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;

    /* Layout */
    --sidebar-width: 260px;
    --header-height: 64px;
}

/* Dark Mode */
[data-theme="dark"] {
    --bg-primary: var(--gray-900);
    --bg-secondary: var(--gray-950);
    --bg-tertiary: var(--gray-800);
    --bg-elevated: var(--gray-800);
    --bg-input: var(--gray-800);
    --bg-hover: var(--gray-700);

    --text-primary: var(--gray-50);
    --text-secondary: var(--gray-400);
    --text-muted: var(--gray-500);

    --border-light: var(--gray-800);
    --border-default: var(--gray-700);

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
}

/* =================================================================
   2. RESET & BASE
   ================================================================= */

*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    font-size: 0.9375rem;
    line-height: 1.5;
    color: var(--text-primary);
    background: var(--bg-secondary);
    min-height: 100vh;
}

a {
    color: var(--accent);
    text-decoration: none;
}

a:hover {
    color: var(--accent-hover);
}

img {
    max-width: 100%;
    height: auto;
}

/* =================================================================
   3. TYPOGRAPHY
   ================================================================= */

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.25;
    color: var(--text-primary);
}

h1 { font-size: 1.875rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.125rem; }
h5 { font-size: 1rem; }
h6 { font-size: 0.875rem; }

.text-muted { color: var(--text-muted); }
.text-secondary { color: var(--text-secondary); }
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-danger { color: var(--danger); }
.text-mono { font-family: var(--font-mono); }
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-sm { font-size: 0.875rem; }
.text-xs { font-size: 0.75rem; }
.text-lg { font-size: 1.125rem; }
.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }

/* =================================================================
   4. LAYOUT
   ================================================================= */

/* Container */
.container {
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

/* Page Layout with Sidebar */
.app-layout {
    display: flex;
    min-height: 100vh;
}

.app-sidebar {
    width: var(--sidebar-width);
    background: var(--bg-sidebar);
    color: var(--text-inverse);
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    z-index: 100;
    overflow-y: auto;
}

.app-main {
    flex: 1;
    margin-left: var(--sidebar-width);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.app-content {
    flex: 1;
    padding: var(--space-xl);
}

/* Page Header */
.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-xl);
}

.page-title {
    font-size: 1.5rem;
    font-weight: 600;
}

.page-actions {
    display: flex;
    gap: var(--space-sm);
}

/* Flex Utilities */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.flex-center { align-items: center; justify-content: center; }
.flex-between { justify-content: space-between; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.items-end { align-items: flex-end; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.justify-end { justify-content: flex-end; }
.flex-1 { flex: 1; }

/* Gap Utilities */
.gap-xs { gap: var(--space-xs); }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }
.gap-xl { gap: var(--space-xl); }

/* Grid */
.grid {
    display: grid;
    gap: var(--space-lg);
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 1024px) {
    .grid-4 { grid-template-columns: repeat(2, 1fr); }
    .grid-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    .grid-4, .grid-3, .grid-2 { grid-template-columns: 1fr; }
    .app-sidebar { transform: translateX(-100%); }
    .app-main { margin-left: 0; }
}

/* =================================================================
   5. COMPONENTS
   ================================================================= */

/* ----- BUTTONS ----- */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: 0.625rem 1rem;
    font-family: inherit;
    font-size: 0.875rem;
    font-weight: 500;
    line-height: 1;
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.btn:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Primary - Dark gray (DevScan style) */
.btn-primary {
    background: var(--gray-900);
    color: white;
    border-color: var(--gray-900);
}

.btn-primary:hover:not(:disabled) {
    background: var(--gray-800);
}

[data-theme="dark"] .btn-primary {
    background: var(--gray-100);
    color: var(--gray-900);
    border-color: var(--gray-100);
}

[data-theme="dark"] .btn-primary:hover:not(:disabled) {
    background: white;
}

/* Secondary - Outlined */
.btn-secondary {
    background: transparent;
    color: var(--text-secondary);
    border-color: var(--border-default);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--bg-hover);
    border-color: var(--gray-400);
}

/* Ghost - No border */
.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    border-color: transparent;
}

.btn-ghost:hover:not(:disabled) {
    background: var(--bg-hover);
}

/* Status Buttons */
.btn-success {
    background: var(--success);
    color: white;
    border-color: var(--success);
}

.btn-success:hover:not(:disabled) {
    background: var(--success-hover);
}

.btn-danger {
    background: var(--danger);
    color: white;
    border-color: var(--danger);
}

.btn-danger:hover:not(:disabled) {
    background: var(--danger-hover);
}

.btn-warning {
    background: var(--warning);
    color: var(--gray-900);
    border-color: var(--warning);
}

/* Button Sizes */
.btn-sm {
    padding: 0.375rem 0.75rem;
    font-size: 0.8125rem;
}

.btn-lg {
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
}

.btn-icon {
    padding: 0.5rem;
    width: 36px;
    height: 36px;
}

/* Full Width */
.btn-block {
    width: 100%;
}

/* ----- CARDS ----- */

.card {
    background: var(--bg-elevated);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.card-header {
    padding: var(--space-md) var(--space-lg);
    border-bottom: 1px solid var(--border-light);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.card-title {
    font-size: 1rem;
    font-weight: 600;
    margin: 0;
}

.card-body {
    padding: var(--space-lg);
}

.card-footer {
    padding: var(--space-md) var(--space-lg);
    border-top: 1px solid var(--border-light);
    background: var(--bg-secondary);
}

/* Stat Card */
.stat-card {
    padding: var(--space-lg);
}

.stat-card .stat-value {
    font-size: 2rem;
    font-weight: 700;
    line-height: 1;
}

.stat-card .stat-label {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-top: var(--space-xs);
}

/* ----- FORMS ----- */

.form-group {
    margin-bottom: var(--space-lg);
}

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: var(--space-xs);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: 0.625rem 0.875rem;
    font-family: inherit;
    font-size: 0.9375rem;
    color: var(--text-primary);
    background: var(--bg-input);
    border: 1px solid var(--border-default);
    border-radius: var(--radius-md);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.form-input::placeholder {
    color: var(--text-muted);
}

.form-textarea {
    min-height: 100px;
    resize: vertical;
}

.form-select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3E%3Cpath stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='m6 8 4 4 4-4'/%3E%3C/svg%3E");
    background-position: right 0.5rem center;
    background-repeat: no-repeat;
    background-size: 1.5em 1.5em;
    padding-right: 2.5rem;
}

.form-hint {
    font-size: 0.8125rem;
    color: var(--text-muted);
    margin-top: var(--space-xs);
}

.form-error {
    font-size: 0.8125rem;
    color: var(--danger);
    margin-top: var(--space-xs);
}

/* Input with addon */
.input-group {
    display: flex;
}

.input-group .form-input {
    border-radius: var(--radius-md) 0 0 var(--radius-md);
}

.input-group .btn {
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

/* Checkbox & Radio */
.form-check {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    cursor: pointer;
}

.form-check input[type="checkbox"],
.form-check input[type="radio"] {
    width: 1rem;
    height: 1rem;
    cursor: pointer;
}

/* Form Row (horizontal layout) */
.form-row {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-lg);
}

@media (max-width: 768px) {
    .form-row {
        grid-template-columns: 1fr;
    }
}

/* ----- TABLES ----- */

.table-container {
    overflow-x: auto;
}

.table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.875rem;
}

.table th,
.table td {
    padding: 0.75rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-light);
}

.table th {
    font-weight: 600;
    color: var(--text-secondary);
    background: var(--bg-secondary);
    white-space: nowrap;
}

.table tbody tr:hover {
    background: var(--bg-hover);
}

.table tbody tr:last-child td {
    border-bottom: none;
}

/* Table inside card */
.card .table th:first-child,
.card .table td:first-child {
    padding-left: var(--space-lg);
}

.card .table th:last-child,
.card .table td:last-child {
    padding-right: var(--space-lg);
}

/* ----- LIST ----- */

.list {
    list-style: none;
}

.list-item {
    padding: var(--space-md) var(--space-lg);
    border-bottom: 1px solid var(--border-light);
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.list-item:last-child {
    border-bottom: none;
}

.list-item:hover {
    background: var(--bg-hover);
}

.list-header {
    padding: var(--space-sm) var(--space-lg);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    background: var(--bg-secondary);
}

.list-empty {
    padding: var(--space-xl);
    text-align: center;
    color: var(--text-muted);
}

/* ----- BADGES ----- */

.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.625rem;
    font-size: 0.75rem;
    font-weight: 500;
    border-radius: var(--radius-full);
    background: var(--bg-tertiary);
    color: var(--text-secondary);
}

.badge-success {
    background: rgba(34, 197, 94, 0.1);
    color: var(--success);
}

.badge-warning {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning);
}

.badge-danger {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
}

.badge-primary {
    background: rgba(59, 130, 246, 0.1);
    color: var(--accent);
}

/* ----- MODALS ----- */

.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-base), visibility var(--transition-base);
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--bg-elevated);
    border-radius: var(--radius-xl);
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transform: scale(0.95);
    transition: transform var(--transition-base);
}

.modal-overlay.active .modal {
    transform: scale(1);
}

.modal-lg { max-width: 700px; }
.modal-xl { max-width: 900px; }
.modal-full { max-width: calc(100vw - 4rem); }

.modal-header {
    padding: var(--space-lg);
    border-bottom: 1px solid var(--border-light);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-title {
    font-size: 1.125rem;
    font-weight: 600;
    margin: 0;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0;
    line-height: 1;
}

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

.modal-body {
    padding: var(--space-lg);
    overflow-y: auto;
    flex: 1;
}

.modal-footer {
    padding: var(--space-md) var(--space-lg);
    border-top: 1px solid var(--border-light);
    display: flex;
    justify-content: flex-end;
    gap: var(--space-sm);
}

/* ----- ALERTS ----- */

.alert {
    padding: var(--space-md) var(--space-lg);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-lg);
    display: flex;
    align-items: flex-start;
    gap: var(--space-sm);
}

.alert-success {
    background: rgba(34, 197, 94, 0.1);
    border: 1px solid rgba(34, 197, 94, 0.2);
    color: var(--success);
}

.alert-warning {
    background: rgba(245, 158, 11, 0.1);
    border: 1px solid rgba(245, 158, 11, 0.2);
    color: var(--warning);
}

.alert-danger {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.2);
    color: var(--danger);
}

.alert-info {
    background: rgba(59, 130, 246, 0.1);
    border: 1px solid rgba(59, 130, 246, 0.2);
    color: var(--accent);
}

/* ----- TOAST NOTIFICATIONS ----- */

.toast-container {
    position: fixed;
    top: var(--space-lg);
    right: var(--space-lg);
    z-index: 1100;
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.toast {
    background: var(--bg-elevated);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: var(--space-md) var(--space-lg);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    min-width: 300px;
    max-width: 400px;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* ----- DROPDOWN ----- */

.dropdown {
    position: relative;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    right: 0;
    background: var(--bg-elevated);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    min-width: 180px;
    padding: var(--space-xs) 0;
    z-index: 100;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: all var(--transition-fast);
}

.dropdown.active .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(4px);
}

.dropdown-item {
    display: block;
    padding: var(--space-sm) var(--space-md);
    color: var(--text-primary);
    font-size: 0.875rem;
}

.dropdown-item:hover {
    background: var(--bg-hover);
}

.dropdown-divider {
    height: 1px;
    background: var(--border-light);
    margin: var(--space-xs) 0;
}

/* ----- TABS ----- */

.tabs {
    display: flex;
    border-bottom: 1px solid var(--border-light);
    gap: var(--space-xs);
}

.tab {
    padding: var(--space-sm) var(--space-md);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-muted);
    border-bottom: 2px solid transparent;
    margin-bottom: -1px;
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

.tab.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

.tab-content {
    display: none;
    padding: var(--space-lg) 0;
}

.tab-content.active {
    display: block;
}

/* ----- LOADING ----- */

.loading {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
}

.spinner {
    width: 1rem;
    height: 1rem;
    border: 2px solid var(--border-default);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

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

.spinner-lg {
    width: 2rem;
    height: 2rem;
    border-width: 3px;
}

/* =================================================================
   6. UTILITIES
   ================================================================= */

/* Spacing */
.m-0 { margin: 0; }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }

.p-0 { padding: 0; }
.p-sm { padding: var(--space-sm); }
.p-md { padding: var(--space-md); }
.p-lg { padding: var(--space-lg); }

/* Display */
.hidden { display: none !important; }
.block { display: block; }
.inline-block { display: inline-block; }

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

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

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

/* Cursor */
.cursor-pointer { cursor: pointer; }
.cursor-not-allowed { cursor: not-allowed; }

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

/* Border */
.border { border: 1px solid var(--border-light); }
.border-top { border-top: 1px solid var(--border-light); }
.border-bottom { border-bottom: 1px solid var(--border-light); }
.rounded { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }

/* Background */
.bg-primary { background: var(--bg-primary); }
.bg-secondary { background: var(--bg-secondary); }

/* States */
.disabled {
    opacity: 0.5;
    pointer-events: none;
}

.success { color: var(--success); }
.warning { color: var(--warning); }
.danger { color: var(--danger); }
.error { color: var(--danger); }

/* Truncate */
.truncate {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* Screen Reader Only */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}