/* =============================================
   MODERN PROFESSIONAL 2025 UI STYLESHEET
   Clean, Minimal, Responsive Design
   ============================================= */

/* ========== CSS VARIABLES (2025 Color Palette) ========== */
:root {
    /* Primary Colors - Modern Blue 2025 (Standardized) */
    --primary-50: #EFF6FF;
    --primary-100: #DBEAFE;
    --primary-200: #BFDBFE;
    --primary-300: #93C5FD;
    --primary-400: #60A5FA;
    --primary-500: #3B82F6;
    --primary-600: #2563EB;
    --primary-700: #1D4ED8;
    --primary-800: #1E40AF;
    --primary-900: #1E3A8A;
    
    /* Legacy aliases (for backward compatibility) */
    --primary-color: var(--primary-500);
    --primary-dark: var(--primary-600);
    --primary-light: var(--primary-100);
    --primary-gradient: linear-gradient(135deg, var(--primary-500) 0%, var(--primary-600) 100%);
    
    /* Success Colors */
    --success-50: #ECFDF5;
    --success-100: #D1FAE5;
    --success-500: #10B981;
    --success-600: #059669;
    --success-700: #047857;
    
    /* Warning Colors */
    --warning-50: #FFFBEB;
    --warning-100: #FEF3C7;
    --warning-500: #F59E0B;
    --warning-600: #D97706;
    --warning-700: #B45309;
    
    /* Danger Colors */
    --danger-50: #FEF2F2;
    --danger-100: #FEE2E2;
    --danger-500: #EF4444;
    --danger-600: #DC2626;
    --danger-700: #B91C1C;
    
    /* Info Colors */
    --info-50: #ECFEFF;
    --info-100: #CFFAFE;
    --info-500: #06B6D4;
    --info-600: #0891B2;
    --info-700: #0E7490;
    
    /* Legacy accent aliases */
    --accent-success: var(--success-500);
    --accent-warning: var(--warning-500);
    --accent-danger: var(--danger-500);
    --accent-info: var(--info-500);
    
    /* Neutral/Gray Colors (Standardized) */
    --gray-50: #F9FAFB;
    --gray-100: #F3F4F6;
    --gray-200: #E5E7EB;
    --gray-300: #D1D5DB;
    --gray-400: #9CA3AF;
    --gray-500: #6B7280;
    --gray-600: #4B5563;
    --gray-700: #374151;
    --gray-800: #1F2937;
    --gray-900: #111827;
    
    /* Text Colors (using gray scale) */
    --text-primary: var(--gray-900);
    --text-secondary: var(--gray-600);
    --text-light: var(--gray-500);
    --text-muted: var(--gray-400);
    
    /* Border Colors */
    --border-color: var(--gray-200);
    --border-light: var(--gray-100);
    
    /* Background Colors */
    --bg-primary: #FFFFFF;
    --bg-secondary: var(--gray-50);
    --bg-tertiary: var(--gray-100);
    --bg-dark: var(--gray-800);
    
    /* Layout */
    --container-max-width: 1400px;
    --sidebar-width: 260px;
    --header-height: 70px;
    --border-radius: 12px;
    --border-radius-sm: 8px;
    --box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --box-shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --box-shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --box-shadow-hover: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    /* Transitions - Smooth animations */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.15s ease-in-out;
    --transition-smooth: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ========== RESET & BASE ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    font-size: 14px;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-secondary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

html {
    scroll-behavior: smooth;
}

/* ========== TYPOGRAPHY ========== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.3;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.125rem; }

p {
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

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

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

/* ========== LAYOUT ========== */
.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 2rem;
}

@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }
}

/* ========== NAVIGATION (Header - Chú thích) ========== */
.navbar {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    padding: 0;
    box-shadow: var(--box-shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar-content {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    min-height: var(--header-height);
}

.navbar-brand {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.navbar-brand i {
    font-size: 1.75rem;
}

.navbar-menu {
    display: flex;
    gap: 0.5rem;
    align-items: center;
    flex-wrap: wrap;
}

.navbar-menu a {
    color: var(--text-secondary);
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius-sm);
    transition: var(--transition);
    font-weight: 500;
    font-size: 0.875rem;
    position: relative;
    overflow: hidden;
}

.navbar-menu a::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s ease, left 0.3s ease;
}

.navbar-menu a:hover {
    background: var(--primary-light);
    color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.08);
}

.navbar-menu a:hover::before {
    width: 80%;
    left: 10%;
}

.navbar-menu .active {
    background: var(--primary-color);
    color: white;
    box-shadow: 0 4px 12px rgba(14, 165, 233, 0.3);
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-left: auto;
}

/* ========== DROPDOWN MENU (Optimized 2025) ========== */
.dropdown {
    position: relative;
}

.dropdown-toggle {
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    position: relative;
}

.dropdown-arrow {
    font-size: 0.75rem;
    transition: transform 0.3s ease;
}

/* Rotate arrow when dropdown is open */
.dropdown.open .dropdown-arrow,
.dropdown:hover .dropdown-arrow {
    transform: rotate(180deg);
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    box-shadow: var(--box-shadow-lg);
    min-width: 220px;
    display: none;
    margin-top: 0.5rem;
    z-index: 1001;
    opacity: 0;
    transform: translateY(-10px) scale(0.95);
    transition: opacity 0.3s ease, transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    backdrop-filter: blur(10px);
}

/* Show dropdown on hover (desktop) */
.dropdown:hover .dropdown-menu {
    display: block;
    opacity: 1;
    transform: translateY(0) scale(1);
    animation: dropdownFadeIn 0.3s ease;
}

/* Show dropdown on click (mobile/tablet) */
.dropdown.open .dropdown-menu {
    display: block;
    opacity: 1;
    transform: translateY(0) scale(1);
    animation: dropdownFadeIn 0.3s ease;
}

@keyframes dropdownFadeIn {
    from {
        opacity: 0;
        transform: translateY(-10px) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.dropdown-menu a {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    color: var(--text-secondary);
    border-radius: 0;
    transition: var(--transition);
    position: relative;
}

.dropdown-menu a::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

.dropdown-menu a:hover {
    background: var(--bg-secondary);
    color: var(--primary-color);
    padding-left: 1.25rem;
}

.dropdown-menu a:hover::after {
    width: 100%;
}

.dropdown-menu a.active {
    background: var(--primary-light);
    color: var(--primary-color);
    font-weight: 600;
    border-left: 3px solid var(--primary-color);
}

.dropdown-menu a i {
    width: 18px;
    text-align: center;
}

/* ========== MOBILE MENU (Responsive - Chú thích) ========== */
.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--primary-color);
    cursor: pointer;
    padding: 0.5rem;
    transition: var(--transition);
}

.mobile-menu-toggle:hover {
    color: var(--primary-dark);
}

.user-name {
    color: var(--text-primary);
    font-weight: 600;
    margin-right: 1rem;
}

.btn-logout {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: var(--accent-danger);
    color: white;
    border: none;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.btn-logout::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn-logout:hover::before {
    width: 300px;
    height: 300px;
}

.btn-logout:hover {
    background: #DC2626;
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(239, 68, 68, 0.3);
}

.btn-logout:active {
    transform: translateY(0);
    box-shadow: 0 2px 4px rgba(239, 68, 68, 0.2);
}

/* Mobile Responsive (< 768px) */
@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: block;
    }
    
    .navbar-content {
        padding: 1rem;
    }
    
    .navbar-menu {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--bg-primary);
        border-top: 1px solid var(--border-color);
        box-shadow: var(--box-shadow-lg);
        display: none;
        flex-direction: column;
        gap: 0;
        padding: 1rem 0;
    }
    
    .navbar-menu.mobile-open {
        display: flex;
    }
    
    .navbar-menu .nav-item,
    .navbar-menu .dropdown-toggle {
        width: 100%;
        padding: 0.875rem 1.5rem;
        border-radius: 0;
    }
    
    .dropdown {
        width: 100%;
    }
    
    .dropdown-menu {
        position: static;
        box-shadow: none;
        border: none;
        border-left: 3px solid var(--primary-color);
        margin-top: 0;
        margin-left: 1.5rem;
        background: var(--bg-secondary);
    }
    
    .nav-right {
        width: 100%;
        flex-direction: column;
        align-items: stretch !important;
        gap: 0.5rem;
        padding: 1rem 1.5rem;
        border-top: 1px solid var(--border-color);
    }
    
    .user-name {
        margin-right: 0;
        margin-bottom: 0.5rem;
    }
    
    .btn-logout {
        width: 100%;
        justify-content: center;
    }
}

/* Tablet (768px - 1024px) */
@media (max-width: 1024px) and (min-width: 769px) {
    .navbar-menu {
        gap: 0.25rem;
    }
    
    .navbar-menu a {
        padding: 0.5rem 0.75rem;
        font-size: 0.813rem;
    }
}

/* ========== CARDS (Main Content - Chú thích) ========== */
.card {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    margin-bottom: 1.5rem;
    overflow: hidden;
    transition: var(--transition);
    position: relative;
    border: 1px solid var(--border-color);
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.05), transparent);
    transition: left 0.5s;
}

.card:hover {
    box-shadow: var(--box-shadow-hover);
    transform: translateY(-3px);
    border-color: var(--primary-light);
}

.card:hover::before {
    left: 100%;
}

.card-header {
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--bg-secondary);
}

.card-header h2,
.card-header h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.card-body {
    padding: 1.5rem;
}

/* ========== DASHBOARD STATISTICS (Widget Cards - Chú thích) ========== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--primary-color);
}

.stat-card:hover {
    box-shadow: var(--box-shadow-hover);
    transform: translateY(-3px);
    border-color: var(--primary-light);
}

.stat-card.success::before {
    background: var(--accent-success);
}

.stat-card.warning::before {
    background: var(--accent-warning);
}

.stat-card.danger::before {
    background: var(--accent-danger);
}
    background: var(--accent-danger);
}

.stat-card h3 {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.stat-card .value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
}

/* ========== TABLES ========== */
.table-container {
    overflow-x: auto;
    border-radius: var(--border-radius);
    background: var(--bg-primary);
}

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

thead {
    background: var(--bg-secondary);
}

th {
    padding: 1rem;
    text-align: left;
    font-weight: 600;
    color: var(--text-primary);
    border-bottom: 2px solid var(--border-color);
    white-space: nowrap;
}

td {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-secondary);
}

tbody tr {
    transition: var(--transition);
}

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

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

/* ========== BUTTONS ========== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: var(--border-radius-sm);
    font-weight: 500;
    font-size: 0.875rem;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    white-space: nowrap;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn:active::before {
    width: 300px;
    height: 300px;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--box-shadow-md);
}

.btn-primary {
    background: var(--primary-color);
    color: white;
    border: 1px solid transparent;
}

.btn-primary:hover {
    background: var(--primary-dark);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.btn-success {
    background: var(--accent-success);
    color: white;
    border: 1px solid transparent;
}

.btn-success:hover {
    background: #059669;
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
}

.btn-warning {
    background: var(--accent-warning);
    color: white;
    border: 1px solid transparent;
}

.btn-warning:hover {
    background: #D97706;
    box-shadow: 0 4px 12px rgba(245, 158, 11, 0.3);
}

.btn-danger {
    background: var(--accent-danger);
    color: white;
    border: 1px solid transparent;
}

.btn-danger:hover {
    background: #DC2626;
    box-shadow: 0 4px 12px rgba(239, 68, 68, 0.3);
}

.btn-secondary {
    background: var(--bg-primary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--bg-secondary);
    border-color: var(--text-secondary);
}

.btn-sm {
    padding: 0.375rem 0.75rem;
    font-size: 0.8125rem;
}

.btn-lg {
    padding: 0.875rem 1.75rem;
    font-size: 1rem;
}

.btn-block {
    width: 100%;
    justify-content: center;
}

/* ========== FORMS ========== */
.form-group {
    margin-bottom: 1.25rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-primary);
    font-size: 0.875rem;
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="number"],
input[type="date"],
input[type="tel"],
select,
textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    font-size: 0.875rem;
    transition: var(--transition);
    background: var(--bg-primary);
    color: var(--text-primary);
}

input:focus,
select:focus,
textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px var(--primary-light);
}

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

.search-bar {
    display: flex;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
}

.search-bar input {
    flex: 1;
}

/* ========== MODAL ========== */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 9999;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(4px);
}

.modal.open {
    display: flex;
}

.modal-content {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    max-width: 600px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 20px 25px rgba(0, 0, 0, 0.15);
    animation: slideUp 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

@keyframes slideUp {
    from {
        transform: translateY(20px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.modal-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h2 {
    margin: 0;
    font-size: 1.25rem;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-light);
    transition: var(--transition);
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--border-radius-sm);
}

.modal-close:hover {
    background: var(--accent-danger);
    color: white;
    transform: rotate(90deg) scale(1.1);
    box-shadow: 0 4px 8px rgba(239, 68, 68, 0.3);
}

/* ========== BADGES ========== */
.badge {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-primary {
    background: var(--primary-light);
    color: var(--primary-color);
}

.badge-success {
    background: #D1FAE5;
    color: var(--accent-color);
}

.badge-warning {
    background: #FEF3C7;
    color: var(--accent-warning);
}

.badge-danger {
    background: #FEE2E2;
    color: var(--accent-danger);
}

/* ========== ALERTS ========== */
.alert {
    padding: 1rem 1.25rem;
    border-radius: var(--border-radius-sm);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.alert-info {
    background: #DBEAFE;
    color: #1E40AF;
}

.alert-success {
    background: #D1FAE5;
    color: #065F46;
}

.alert-warning {
    background: #FEF3C7;
    color: #92400E;
}

.alert-danger {
    background: #FEE2E2;
    color: #991B1B;
}

/* ========== LANGUAGE SELECTOR (Chú thích) ========== */
.language-selector {
    position: relative;
}

.language-selector select {
    padding: 0.5rem 2rem 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    background: var(--bg-primary);
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%236B7280'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.5rem center;
    background-size: 1rem;
}

/* ========== IMPORT SECTION (Chú thích) ========== */
.import-container {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--box-shadow-md);
    margin-bottom: 1.5rem;
}

.file-upload {
    border: 2px dashed var(--border-color);
    border-radius: var(--border-radius);
    padding: 2rem;
    text-align: center;
    transition: var(--transition);
    cursor: pointer;
}

.file-upload:hover {
    border-color: var(--primary-color);
    background: var(--primary-light);
}

.file-upload input[type="file"] {
    display: none;
}

.file-upload-label {
    cursor: pointer;
    color: var(--text-secondary);
}

.file-upload-label i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

/* ========== LOADING SPINNER ========== */
.loading {
    display: inline-block;
    width: 1rem;
    height: 1rem;
    border: 2px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

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

/* ========== FOOTER (Chú thích) ========== */
.footer {
    background: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    padding: 2rem 0;
    margin-top: 3rem;
    text-align: center;
    color: var(--text-secondary);
}

/* ========== LOGIN PAGE ========== */
.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-gradient);
}

.login-box {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow-lg);
    padding: 3rem;
    width: 100%;
    max-width: 420px;
}

.login-box h1 {
    text-align: center;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

/* ========== RESPONSIVE ========== */
@media (max-width: 768px) {
    .navbar-content {
        flex-direction: column;
        gap: 1rem;
    }

    .navbar-menu {
        width: 100%;
        justify-content: center;
    }

    .stats-grid {
        grid-template-columns: 1fr;
    }

    .card-header {
        flex-direction: column;
        gap: 1rem;
        align-items: flex-start;
    }

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

/* ========== UTILITIES ========== */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-left { text-align: left; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.flex { display: flex; }
.flex-between { display: flex; justify-content: space-between; align-items: center; }
.flex-center { display: flex; justify-content: center; align-items: center; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }
.gap-3 { gap: 1.5rem; }
.hidden { display: none; }
.visible { display: block; }

/* ========== PRINT STYLES ========== */
@media print {
    .navbar,
    .btn,
    .search-bar,
    .modal {
        display: none !important;
    }
    
    body {
        background: white;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid var(--border-color);
    }
}