/* ========================================
   SENDHOME PLATFORM - BASE STYLES
   Global, dynamic design system for web app.
   All sizing/colors live in :root — override
   in your page or a custom CSS file to customize.
   ======================================== */

/* CSS Variables - Design System (all dynamic) */
:root {
    /* Brand Colors */
    --color-primary: #190039;        /* Deep Purple */
    --color-secondary: #ed048e;      /* Bright Pink */
    --color-accent: #f5f5dc;         /* Beige */
    
    /* Neutral Colors */
    --color-white: #ffffff;
    --color-black: #000000;
    --color-gray-light: #f8f9fa;
    --color-gray: #6c757d;
    --color-gray-dark: #343a40;
    
    /* Status Colors */
    --color-success: #28a745;
    --color-error: #dc3545;
    --color-warning: #ffc107;
    --color-info: #17a2b8;
    
    /* Typography - clean system font (Helvetica-like on iOS/macOS) */
    --font-family-primary: -apple-system, BlinkMacSystemFont, "Helvetica Neue", Helvetica, Arial, sans-serif;
    --font-family-heading: -apple-system, BlinkMacSystemFont, "Helvetica Neue", Helvetica, Arial, sans-serif;
    
    /* App-appropriate font sizes (compact, not marketing-sized) */
    --font-size-xs: 0.6875rem;   /* 11px */
    --font-size-sm: 0.8125rem;   /* 13px */
    --font-size-base: 0.875rem;  /* 14px - app body */
    --font-size-lg: 1rem;        /* 16px */
    --font-size-xl: 1.125rem;    /* 18px */
    --font-size-2xl: 1.25rem;    /* 20px */
    --font-size-3xl: 1.5rem;     /* 24px */
    --font-size-4xl: 1.75rem;    /* 28px */
    
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    /* Spacing - denser for web app */
    --spacing-xs: 0.25rem;   /* 4px */
    --spacing-sm: 0.375rem;  /* 6px */
    --spacing-md: 0.75rem;   /* 12px */
    --spacing-lg: 1rem;      /* 16px */
    --spacing-xl: 1.25rem;   /* 20px */
    --spacing-2xl: 1.5rem;   /* 24px */
    --spacing-3xl: 2rem;     /* 32px */
    
    /* Component sizing - override per context if needed */
    --btn-padding-y: 0.375rem;   /* 6px */
    --btn-padding-x: 0.875rem;   /* 14px */
    --btn-font-size: var(--font-size-base);
    --input-padding-y: 0.375rem;
    --input-padding-x: 0.625rem;
    --input-font-size: var(--font-size-base);
    --header-height: 52px;
    --logo-height: 32px;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    --radius-xl: 10px;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 2px 4px -1px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 4px 8px -2px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 8px 16px -4px rgba(0, 0, 0, 0.1);
    
    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 200ms ease-in-out;
    --transition-slow: 300ms ease-in-out;
    
    /* Layout */
    --max-width-container: 1200px;
    --max-width-content: 800px;
    --sidebar-width: 220px;
}

/* ========================================
   RESET & BASE STYLES
   ======================================== */

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family-primary);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-normal);
    line-height: 1.5;
    color: var(--color-gray-dark);
    background-color: var(--color-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-family-heading);
    font-weight: var(--font-weight-bold);
    line-height: 1.25;
    color: var(--color-primary);
    margin-bottom: var(--spacing-sm);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }
h5 { font-size: var(--font-size-lg); }
h6 { font-size: var(--font-size-base); }

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

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

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

/* ========================================
   LAYOUT COMPONENTS
   ======================================== */

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

.container-narrow {
    max-width: var(--max-width-content);
}

/* App layout: header + sidebar + main */
.app-layout {
    display: flex;
    min-height: 100vh;
    flex-direction: column;
}

.app-body {
    display: flex;
    flex: 1;
    min-height: calc(100vh - var(--header-height));
}

/* Header - top bar: logo left, search + profile right */
.header {
    background-color: var(--color-white);
    border-bottom: 1px solid var(--color-accent);
    height: var(--header-height);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow-sm);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    padding: 0 var(--spacing-md);
    max-width: none;
}

.header .container {
    max-width: none;
    padding: 0 var(--spacing-md);
}

.header-left {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.header-right {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.logo {
    height: var(--logo-height);
    width: auto;
}

/* Header search */
.header-search {
    width: 200px;
    padding: var(--spacing-xs) var(--spacing-sm) var(--spacing-xs) var(--spacing-md);
    font-size: var(--font-size-sm);
    border: 1px solid var(--color-gray-light);
    border-radius: var(--radius-md);
    background-color: var(--color-white);
    transition: border-color var(--transition-fast);
}

.header-search:focus {
    outline: none;
    border-color: var(--color-secondary);
}

.header-search::placeholder {
    color: var(--color-gray);
}

.header-search-form {
    display: flex;
}

/* Header profile link */
.header-profile {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--color-primary);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.header-profile .icon {
    flex-shrink: 0;
}

.header-profile:hover {
    background-color: var(--color-gray-light);
    color: var(--color-secondary);
}

/* Sidebar - all navigation */
.sidebar {
    width: var(--sidebar-width);
    flex-shrink: 0;
    background-color: var(--color-white);
    border-right: 1px solid var(--color-accent);
    padding: var(--spacing-md) 0;
    overflow-y: auto;
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.sidebar-link {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--color-primary);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    text-decoration: none;
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    border-left: 3px solid transparent;
    transition: all var(--transition-fast);
}

.sidebar-link .icon {
    flex-shrink: 0;
}

.sidebar-link:hover {
    background-color: var(--color-gray-light);
    color: var(--color-secondary);
}

.sidebar-link.active {
    background-color: var(--color-accent);
    color: var(--color-primary);
    border-left-color: var(--color-secondary);
}

/* Navigation (legacy / inline use) */
.nav {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.nav-link {
    color: var(--color-primary);
    font-weight: var(--font-weight-medium);
    font-size: var(--font-size-sm);
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.nav-link:hover {
    background-color: var(--color-gray-light);
    color: var(--color-secondary);
}

.nav-link.active {
    background-color: var(--color-primary);
    color: var(--color-white);
}

/* Main Content - beside sidebar */
.main-content {
    flex: 1;
    min-height: calc(100vh - var(--header-height));
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

/* ========================================
   TAB SYSTEM
   ======================================== */

/* Tab Bar Container */
.tab-bar {
    display: flex;
    align-items: center;
    background-color: var(--color-gray-light);
    border-bottom: 1px solid var(--color-accent);
    padding: 0 var(--spacing-xs);
    min-height: 38px;
    gap: var(--spacing-xs);
}

/* Tab List - scrollable container for tabs */
.tab-list {
    display: flex;
    flex: 1;
    overflow-x: auto;
    overflow-y: hidden;
    gap: 2px;
    padding: var(--spacing-xs) 0;
    scrollbar-width: none;
    -ms-overflow-style: none;
}

.tab-list::-webkit-scrollbar {
    display: none;
}

/* Individual Tab */
.tab {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
    background-color: var(--color-white);
    border: 1px solid transparent;
    border-bottom: none;
    border-radius: var(--radius-md) var(--radius-md) 0 0;
    cursor: pointer;
    font-size: var(--font-size-sm);
    color: var(--color-gray);
    white-space: nowrap;
    max-width: 180px;
    min-width: 100px;
    transition: all var(--transition-fast);
    position: relative;
    flex-shrink: 0;
}

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

.tab.active {
    background-color: var(--color-white);
    color: var(--color-primary);
    border-color: var(--color-accent);
    box-shadow: 0 2px 0 0 var(--color-white);
    z-index: 1;
}

.tab.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    right: 0;
    height: 2px;
    background-color: var(--color-secondary);
}

/* Tab Icon */
.tab-icon {
    flex-shrink: 0;
    opacity: 0.7;
}

.tab.active .tab-icon {
    opacity: 1;
}

/* Tab Title */
.tab-title {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    font-weight: var(--font-weight-medium);
}

/* Pinned Tab */
.tab.pinned {
    min-width: auto;
    padding-right: var(--spacing-sm);
}

.tab-pin-icon {
    opacity: 0.5;
    display: flex;
    align-items: center;
}

/* Tab Close Button */
.tab-close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 18px;
    height: 18px;
    padding: 0;
    border: none;
    background: transparent;
    border-radius: var(--radius-sm);
    cursor: pointer;
    opacity: 0;
    transition: all var(--transition-fast);
    color: var(--color-gray);
    flex-shrink: 0;
}

.tab:hover .tab-close,
.tab.active .tab-close {
    opacity: 0.6;
}

.tab-close:hover {
    opacity: 1 !important;
    background-color: var(--color-error);
    color: var(--color-white);
}

/* Tab Loading State */
.tab.loading .tab-title {
    opacity: 0.6;
}

.tab-loader {
    width: 12px;
    height: 12px;
    border: 2px solid var(--color-gray-light);
    border-top-color: var(--color-secondary);
    border-radius: 50%;
    animation: tab-spin 0.8s linear infinite;
    flex-shrink: 0;
}

.tab:not(.loading) .tab-loader {
    display: none;
}

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

/* Tab Error State */
.tab.error {
    color: var(--color-error);
}

.tab.error .tab-title {
    opacity: 0.8;
}

/* Tab Scroll Buttons */
.tab-actions {
    display: flex;
    gap: 2px;
    flex-shrink: 0;
}

.tab-scroll-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    padding: 0;
    border: none;
    background-color: transparent;
    border-radius: var(--radius-sm);
    cursor: pointer;
    color: var(--color-gray);
    transition: all var(--transition-fast);
}

.tab-scroll-btn:hover {
    background-color: var(--color-white);
    color: var(--color-primary);
}

/* Tab Content Container */
.tab-content-container {
    flex: 1;
    overflow: auto;
    padding: var(--spacing-lg);
    background-color: var(--color-white);
}

/* Individual Tab Content */
.tab-content {
    display: none;
    height: 100%;
}

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

/* Tab Loading Spinner */
.tab-loading-spinner {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 200px;
    color: var(--color-gray);
}

.tab-loading-spinner .spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--color-gray-light);
    border-top-color: var(--color-secondary);
    border-radius: 50%;
    animation: tab-spin 0.8s linear infinite;
    margin-bottom: var(--spacing-md);
}

.tab-loading-spinner p {
    font-size: var(--font-size-sm);
    margin: 0;
}

/* Tab Error Display */
.tab-error {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 200px;
    text-align: center;
    color: var(--color-gray);
    padding: var(--spacing-xl);
}

.tab-error svg {
    color: var(--color-error);
    margin-bottom: var(--spacing-md);
}

.tab-error h3 {
    color: var(--color-error);
    margin-bottom: var(--spacing-xs);
}

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

/* Sidebar Section Label */
.sidebar-section-label {
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-gray);
    padding: var(--spacing-md) var(--spacing-md) var(--spacing-xs);
    margin-top: var(--spacing-sm);
}

/* Sidebar Dropdown */
.sidebar-dropdown {
    margin: var(--spacing-xs) 0;
}

.sidebar-dropdown-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    cursor: pointer;
    color: var(--color-text);
    font-weight: var(--font-weight-medium);
    transition: all 0.2s;
    border-radius: var(--border-radius);
}

.sidebar-dropdown-header:hover {
    background-color: var(--color-gray-light);
    color: var(--color-primary);
}

.sidebar-dropdown-header .icon {
    flex-shrink: 0;
}

.sidebar-dropdown-header span {
    flex: 1;
}

.sidebar-dropdown-header .dropdown-arrow {
    flex-shrink: 0;
    transition: transform 0.3s;
}

.sidebar-dropdown.open .dropdown-arrow {
    transform: rotate(180deg);
}

.sidebar-dropdown-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
}

.sidebar-dropdown.open .sidebar-dropdown-content {
    max-height: 500px;
}

.sidebar-sublink {
    padding-left: calc(var(--spacing-md) + 18px + var(--spacing-sm));
    font-size: var(--font-size-sm);
}

.sidebar-sublink .icon {
    width: 16px;
    height: 16px;
}

/* Sidebar Collapsible Groups */
.sidebar-group {
    margin: 0;
}
.sidebar-group-toggle {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md);
    background: none;
    border: none;
    border-left: 3px solid transparent;
    color: var(--color-primary);
    font-size: var(--font-size-sm);
    font-weight: 500;
    cursor: pointer;
    text-align: left;
    transition: background 0.15s;
}
.sidebar-group-toggle:hover {
    background-color: var(--color-gray-light);
}
.sidebar-group-toggle .icon {
    flex-shrink: 0;
}
.sidebar-group-toggle span {
    flex: 1;
}
.sidebar-chevron {
    flex-shrink: 0;
    transition: transform 0.2s;
}
.sidebar-group.open .sidebar-chevron {
    transform: rotate(180deg);
}
.sidebar-group-items {
    display: none;
    padding-left: 0.75rem;
}
.sidebar-group.open .sidebar-group-items {
    display: block;
}
.sidebar-sublink {
    padding-left: 2.25rem !important;
    font-size: 0.8125rem;
    border-left: none !important;
}
.sidebar-sublink::before {
    content: '';
    width: 5px;
    height: 5px;
    border-radius: 50%;
    background: var(--color-gray);
    flex-shrink: 0;
    margin-right: 0.5rem;
}

/* Footer */
.footer {
    background-color: var(--color-primary);
    color: var(--color-white);
    padding: var(--spacing-lg) 0 var(--spacing-md);
    margin-top: var(--spacing-2xl);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.footer-section h4 {
    color: var(--color-secondary);
    font-size: var(--font-size-sm);
    margin-bottom: var(--spacing-sm);
}

.footer-section a,
.footer-section p {
    font-size: var(--font-size-sm);
}

.footer-section a {
    color: var(--color-white);
    display: block;
    margin-bottom: var(--spacing-xs);
}

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

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: var(--spacing-md);
    text-align: center;
    color: var(--color-accent);
    font-size: var(--font-size-sm);
}

/* ========================================
   BUTTONS
   ======================================== */

.btn {
    display: inline-block;
    font-weight: var(--font-weight-semibold);
    font-size: var(--btn-font-size);
    text-align: center;
    vertical-align: middle;
    cursor: pointer;
    border: 1px solid transparent;
    padding: var(--btn-padding-y) var(--btn-padding-x);
    line-height: 1.4;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    text-decoration: none;
}

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

/* Primary Button */
.btn-primary {
    background-color: var(--color-secondary);
    color: var(--color-white);
    border: 1px solid var(--color-secondary);
}

.btn-primary:hover:not(:disabled) {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
    color: var(--color-white);
}

/* Secondary Button */
.btn-secondary {
    background-color: var(--color-primary);
    color: var(--color-white);
    border: 1px solid var(--color-primary);
}

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

/* Outline Button */
.btn-outline {
    background-color: transparent;
    color: var(--color-primary);
    border: 1px solid var(--color-primary);
}

.btn-outline:hover:not(:disabled) {
    background-color: var(--color-primary);
    color: var(--color-white);
}

/* Button Sizes */
.btn-sm {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: var(--font-size-sm);
}

.btn-lg {
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--font-size-lg);
}

.btn-block {
    display: block;
    width: 100%;
}

/* ========================================
   FORMS
   ======================================== */

.form-group {
    margin-bottom: var(--spacing-md);
}

.form-label {
    display: block;
    font-weight: var(--font-weight-medium);
    font-size: var(--font-size-sm);
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
}

.form-control {
    display: block;
    width: 100%;
    padding: var(--input-padding-y) var(--input-padding-x);
    font-size: var(--input-font-size);
    line-height: 1.4;
    color: var(--color-gray-dark);
    background-color: var(--color-white);
    border: 1px solid var(--color-gray-light);
    border-radius: var(--radius-md);
    transition: border-color var(--transition-fast);
}

.form-control:focus {
    outline: none;
    border-color: var(--color-secondary);
    box-shadow: 0 0 0 2px rgba(237, 4, 142, 0.12);
}

.form-control:disabled {
    background-color: var(--color-gray-light);
    cursor: not-allowed;
}

.form-control.error {
    border-color: var(--color-error);
}

.form-text {
    display: block;
    margin-top: var(--spacing-xs);
    font-size: var(--font-size-sm);
    color: var(--color-gray);
}

.form-error {
    color: var(--color-error);
    font-size: var(--font-size-sm);
    margin-top: var(--spacing-xs);
}

/* Select */
select.form-control {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='10' viewBox='0 0 12 12'%3E%3Cpath fill='%23190039' d='M6 9L1 4h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right var(--spacing-sm) center;
    padding-right: var(--spacing-xl);
}

/* Checkbox & Radio */
.form-check {
    display: flex;
    align-items: center;
    margin-bottom: var(--spacing-xs);
}

.form-check-input {
    width: 16px;
    height: 16px;
    margin-right: var(--spacing-sm);
    cursor: pointer;
}

.form-check-label {
    cursor: pointer;
    margin-bottom: 0;
}

/* ========================================
   CARDS
   ======================================== */

.card {
    background-color: var(--color-white);
    border: 1px solid var(--color-gray-light);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: all var(--transition-base);
}

.card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

.card-header {
    background-color: var(--color-accent);
    padding: var(--spacing-md) var(--spacing-lg);
    border-bottom: 1px solid var(--color-gray-light);
    font-size: var(--font-size-sm);
}

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

.card-footer {
    background-color: var(--color-gray-light);
    padding: var(--spacing-sm) var(--spacing-lg);
    border-top: 1px solid var(--color-gray-light);
}

.card-title {
    color: var(--color-primary);
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--spacing-xs);
}

/* ========================================
   ALERTS
   ======================================== */

.alert {
    padding: var(--spacing-sm) var(--spacing-md);
    margin-bottom: var(--spacing-md);
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
}

.alert-success {
    background-color: #d4edda;
    border-color: var(--color-success);
    color: #155724;
}

.alert-error {
    background-color: #f8d7da;
    border-color: var(--color-error);
    color: #721c24;
}

.alert-warning {
    background-color: #fff3cd;
    border-color: var(--color-warning);
    color: #856404;
}

.alert-info {
    background-color: #d1ecf1;
    border-color: var(--color-info);
    color: #0c5460;
}

/* ========================================
   TABLES
   ======================================== */

.table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-sm);
}

.table th,
.table td {
    padding: var(--spacing-sm) var(--spacing-md);
    text-align: left;
    border-bottom: 1px solid var(--color-gray-light);
}

.table thead th {
    background-color: var(--color-primary);
    color: var(--color-white);
    font-weight: var(--font-weight-semibold);
    font-size: var(--font-size-sm);
    border-bottom: 1px solid var(--color-secondary);
}

.table tbody tr:hover {
    background-color: var(--color-gray-light);
}

.table-striped tbody tr:nth-child(even) {
    background-color: var(--color-gray-light);
}

/* ========================================
   UTILITIES
   ======================================== */

/* Text Alignment */
.text-left { text-align: left; }
.text-center { text-align: center; }
.text-right { text-align: right; }

/* Text Sizes */
.text-xs { font-size: var(--font-size-xs); }
.text-sm { font-size: var(--font-size-sm); }
.text-lg { font-size: var(--font-size-lg); }
.text-xl { font-size: var(--font-size-xl); }

/* Text Colors */
.text-primary { color: var(--color-primary); }
.text-secondary { color: var(--color-secondary); }
.text-accent { color: var(--color-accent); }
.text-white { color: var(--color-white); }
.text-success { color: var(--color-success); }
.text-error { color: var(--color-error); }
.text-warning { color: var(--color-warning); }

/* Background Colors */
.bg-primary { background-color: var(--color-primary); }
.bg-secondary { background-color: var(--color-secondary); }
.bg-accent { background-color: var(--color-accent); }
.bg-light { background-color: var(--color-gray-light); }
.bg-white { background-color: var(--color-white); }

/* Spacing Utilities */
.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }

.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }

.pt-sm { padding-top: var(--spacing-sm); }
.pt-md { padding-top: var(--spacing-md); }
.pt-lg { padding-top: var(--spacing-lg); }
.pt-xl { padding-top: var(--spacing-xl); }

.pb-sm { padding-bottom: var(--spacing-sm); }
.pb-md { padding-bottom: var(--spacing-md); }
.pb-lg { padding-bottom: var(--spacing-lg); }
.pb-xl { padding-bottom: var(--spacing-xl); }

/* Display Utilities */
.d-none { display: none; }
.d-block { display: block; }
.d-inline { display: inline; }
.d-inline-block { display: inline-block; }
.d-flex { display: flex; }
.d-grid { display: grid; }

/* Flex Utilities */
.flex-row { flex-direction: row; }
.flex-column { flex-direction: column; }
.justify-start { justify-content: flex-start; }
.justify-center { justify-content: center; }
.justify-end { justify-content: flex-end; }
.justify-between { justify-content: space-between; }
.align-start { align-items: flex-start; }
.align-center { align-items: center; }
.align-end { align-items: flex-end; }
.gap-sm { gap: var(--spacing-sm); }
.gap-md { gap: var(--spacing-md); }
.gap-lg { gap: var(--spacing-lg); }

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

/* Border Utilities */
.border { border: 2px solid var(--color-gray-light); }
.border-primary { border-color: var(--color-primary); }
.border-secondary { border-color: var(--color-secondary); }
.rounded { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-full { border-radius: var(--radius-full); }

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

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

@media (max-width: 768px) {
    :root {
        --font-size-3xl: 1.375rem;
        --font-size-4xl: 1.5rem;
    }
    
    .app-body {
        flex-direction: column;
    }
    
    .sidebar {
        width: 100%;
        border-right: none;
        border-bottom: 1px solid var(--color-accent);
        padding: var(--spacing-sm) var(--spacing-md);
    }
    
    .sidebar-nav {
        flex-direction: row;
        flex-wrap: wrap;
        gap: var(--spacing-sm);
    }
    
    .sidebar-link {
        border-left: none;
        border-bottom: 3px solid transparent;
        border-radius: var(--radius-md);
    }
    
    .sidebar-link.active {
        border-left: none;
        border-bottom-color: var(--color-secondary);
    }
    
    .sidebar-section-label {
        width: 100%;
        padding: var(--spacing-xs) 0;
        margin-top: var(--spacing-xs);
    }
    
    .header-content {
        flex-wrap: wrap;
        gap: var(--spacing-sm);
    }
    
    .header-search {
        width: 140px;
    }
    
    .nav {
        flex-direction: column;
        width: 100%;
        gap: var(--spacing-sm);
    }
    
    .nav-link {
        width: 100%;
        text-align: center;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
    
    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
    
    /* Tab system responsive */
    .tab-bar {
        min-height: 34px;
    }
    
    .tab {
        padding: var(--spacing-xs) var(--spacing-sm);
        font-size: var(--font-size-xs);
        max-width: 140px;
        min-width: 80px;
    }
    
    .tab-title {
        max-width: 80px;
    }
    
    .tab-content-container {
        padding: var(--spacing-md);
    }
    
    .tab-close {
        width: 16px;
        height: 16px;
    }
}