:root {
    /* Corporate Color Palette - Professional Blue */
    --primary: #2563eb;
    --primary-dark: #1e40af;
    --primary-darker: #1e3a8a;
    --primary-light: #3b82f6;
    --primary-lighter: #60a5fa;
    --primary-lightest: #93c5fd;

    /* Accent Colors */
    --accent: #10b981;
    --accent-light: #34d399;
    --success: #10b981;
    --danger: #dc2626;
    --warning: #f59e0b;
    --info: #0ea5e9;

    /* Neutrals - Clean Grays */
    --white: #ffffff;
    --black: #000000;
    --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;

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

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* Shadows - Subtle */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.08);

    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);

    /* Safe Area */
    --safe-area-top: env(safe-area-inset-top);
    --safe-area-bottom: env(safe-area-inset-bottom);
    --safe-area-left: env(safe-area-inset-left);
    --safe-area-right: env(safe-area-inset-right);

    /* Bottom Nav Height */
    --bottom-nav-height: 64px;
}

/* Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    background: var(--gray-50);
    color: var(--gray-900);
    line-height: 1.5;
    overflow-x: hidden;
    padding-bottom: calc(var(--bottom-nav-height) + var(--safe-area-bottom));
}

/* App Container */
.app-container {
    max-width: 768px;
    margin: 0 auto;
    background: var(--white);
    min-height: 100vh;
    position: relative;
}

/* Top App Bar */
.app-bar {
    position: sticky;
    top: 0;
    left: 0;
    right: 0;
    height: 56px;
    background: var(--white);
    box-shadow: var(--shadow-sm);
    display: flex;
    align-items: center;
    padding: 0 var(--spacing-md);
    z-index: 100;
    border-bottom: 1px solid var(--gray-100);
}

.app-bar-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--gray-900);
    flex: 1;
    text-align: center;
}

.app-bar-back {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    cursor: pointer;
    transition: background var(--transition-fast);
    color: var(--gray-700);
    text-decoration: none;
}

.app-bar-back:hover {
    color: var(--gray-900);
}

.app-bar-back:active {
    background: var(--gray-100);
}

/* Desktop Navigation - Hidden on mobile */
.desktop-nav {
    display: none;
    background: var(--white);
    border-bottom: 1px solid var(--gray-200);
    box-shadow: var(--shadow-sm);
}

.desktop-nav-container {
    max-width: 1024px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--spacing-xl);
    height: 70px;
}

.desktop-nav-brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.desktop-nav-brand:hover {
    transform: scale(1.05);
}

.desktop-nav-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.desktop-nav-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    color: var(--gray-700);
    text-decoration: none;
    font-weight: 500;
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
}

.desktop-nav-link:hover {
    background: var(--gray-100);
    color: var(--primary);
}

.desktop-nav-link.active {
    background: var(--primary-lightest);
    color: var(--primary);
    font-weight: 600;
}

/* Bottom Navigation */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    max-width: 768px;
    width: 100%;
    height: calc(var(--bottom-nav-height) + var(--safe-area-bottom));
    background: var(--white);
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.05);
    display: flex;
    align-items: center;
    justify-content: space-around;
    padding-bottom: var(--safe-area-bottom);
    z-index: 1000;
    border-top: 1px solid var(--gray-100);
}

.nav-item {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.25rem;
    padding: 0.5rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    text-decoration: none;
    color: var(--gray-500);
}

.nav-item.active {
    color: var(--primary);
}

.nav-item .icon {
    font-size: 1.5rem;
    transition: transform var(--transition-fast);
}

.nav-item.active .icon {
    transform: scale(1.1);
}

.nav-item .label {
    font-size: 0.75rem;
    font-weight: 500;
}

.nav-item:active {
    transform: scale(0.95);
}

/* Cards */
.card {
    background: var(--white);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    transition: all var(--transition-base);
    border: 1px solid var(--gray-100);
}

.card:active {
    transform: scale(0.98);
    box-shadow: var(--shadow-sm);
}

/* Category Grid */
.category-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
    padding: var(--spacing-md);
}

/* Category Card - Corporate Blue Shades */
.category-card {
    background: var(--primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    aspect-ratio: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    cursor: pointer;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
}

.category-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0) 100%);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.category-card:active {
    transform: scale(0.95);
}

.category-card:active::before {
    opacity: 1;
}

.category-icon {
    font-size: 3rem;
    color: var(--white);
    filter: drop-shadow(0 2px 4px rgba(0,0,0,0.1));
}

.category-name {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--white);
    text-align: center;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
    white-space: nowrap;
}

.btn-primary {
    background: var(--primary);
    color: var(--white);
    box-shadow: 0 2px 4px rgba(37, 99, 235, 0.2);
}

.btn-primary:active {
    background: var(--primary-dark);
    transform: scale(0.98);
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

.btn-block {
    width: 100%;
}

/* List Items */
.list-item {
    display: flex;
    align-items: center;
    padding: var(--spacing-lg);
    background: var(--white);
    border-bottom: 1px solid var(--gray-100);
    cursor: pointer;
    transition: background var(--transition-fast);
}

.list-item:active {
    background: var(--gray-50);
}

.list-item-icon {
    width: 48px;
    height: 48px;
    background: var(--primary-lightest);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: var(--spacing-md);
    color: var(--primary);
    font-size: 1.5rem;
}

.list-item-content {
    flex: 1;
}

.list-item-title {
    font-weight: 600;
    color: var(--gray-900);
    margin-bottom: 0.25rem;
}

.list-item-subtitle {
    font-size: 0.875rem;
    color: var(--gray-500);
}

/* Badge */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: var(--radius-full);
}

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

.badge-success {
    background: #d1fae5;
    color: #065f46;
}

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

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes scaleIn {
    from {
        transform: scale(0.95);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

.animate-slideUp {
    animation: slideUp 0.4s ease-out;
}

.animate-fadeIn {
    animation: fadeIn 0.3s ease-out;
}

.animate-scaleIn {
    animation: scaleIn 0.3s ease-out;
}

/* Touch Feedback */
.touchable {
    cursor: pointer;
    user-select: none;
    -webkit-user-select: none;
}

.touchable:active {
    opacity: 0.8;
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Hide Scrollbar */
::-webkit-scrollbar {
    width: 0;
    height: 0;
}

/* Page Padding */
.page-content {
    padding: var(--spacing-md);
    padding-bottom: calc(var(--bottom-nav-height) + var(--spacing-md) + var(--safe-area-bottom));
}

/* Form Elements */
.form-group {
    margin-bottom: 1.25rem;
}

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: 0.5rem;
}

.form-input,
.form-textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    font-size: 1rem;
    font-family: inherit;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
    background: var(--white);
    color: var(--gray-900);
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--primary);
    background: var(--primary-lightest);
    background: rgba(37, 99, 235, 0.05);
}

.form-input::placeholder,
.form-textarea::placeholder {
    color: var(--gray-400);
}

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

.form-select {
    width: 100%;
    padding: 0.875rem 1rem;
    font-size: 1rem;
    font-family: inherit;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
    background: var(--white);
    color: var(--gray-900);
    cursor: pointer;
}

.form-select:focus {
    outline: none;
    border-color: var(--primary);
    background: rgba(37, 99, 235, 0.05);
}

.form-checkbox,
.form-radio {
    width: 20px;
    height: 20px;
    accent-color: var(--primary);
    cursor: pointer;
}

/* Button Variations */
.btn-success {
    background: var(--success);
    color: var(--white);
    box-shadow: 0 2px 4px rgba(16, 185, 129, 0.2);
}

.btn-success:active {
    background: #059669;
    transform: scale(0.98);
}

.btn-danger {
    background: var(--danger);
    color: var(--white);
    box-shadow: 0 2px 4px rgba(220, 38, 38, 0.2);
}

.btn-danger:active {
    background: #b91c1c;
    transform: scale(0.98);
}

.btn-outline-primary {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
}

.btn-outline-primary:active {
    background: var(--primary-lightest);
    transform: scale(0.98);
}

.btn-outline-secondary {
    background: transparent;
    color: var(--gray-700);
    border: 2px solid var(--gray-300);
}

.btn-outline-secondary:active {
    background: var(--gray-100);
    transform: scale(0.98);
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

/* Section Styles */
.section-header {
    margin-bottom: 1rem;
}

.section-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--gray-900);
}

/* Bottom Action Container (Mobile Fixed, Desktop Inline) */
.bottom-action {
    position: fixed;
    bottom: calc(var(--bottom-nav-height) + var(--safe-area-bottom));
    left: 50%;
    transform: translateX(-50%);
    max-width: 768px;
    width: 100%;
    background: white;
    padding: 1rem;
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
    border-top: 1px solid var(--gray-100);
    z-index: 999;
}

/* Package Grid */
.packages-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

/* Orders Grid */
.orders-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

/* Alert Styles */
.alert {
    padding: 1rem;
    border-radius: var(--radius-lg);
    margin-bottom: 1rem;
    font-size: 0.95rem;
}

/* Utility Classes */
.me-1 { margin-right: 0.25rem; }
.me-2 { margin-right: 0.5rem; }
.ms-auto { margin-left: auto; }

.alert-success {
    background: #d1fae5;
    color: #065f46;
    border: 1px solid #6ee7b7;
}

.alert-error,
.alert-danger {
    background: #fee2e2;
    color: #991b1b;
    border: 1px solid #fca5a5;
}

.alert-info {
    background: #dbeafe;
    color: #1e40af;
    border: 1px solid #93c5fd;
}

.alert-warning {
    background: #fef3c7;
    color: #92400e;
    border: 1px solid #fcd34d;
}

/* Responsive Breakpoints */

/* Mobile First - Default styles above are for mobile */

/* Tablet - 768px and up */
@media (min-width: 768px) {
    .app-container {
        max-width: 1024px;
        box-shadow: var(--shadow-xl);
    }

    body {
        padding-bottom: 0;
    }

    /* Show desktop nav, hide mobile elements */
    .desktop-nav {
        display: block;
    }

    .app-bar {
        display: none;
    }

    /* Category Grid - 3 columns on tablet */
    .category-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--spacing-lg);
        padding: var(--spacing-lg);
    }

    /* Hide bottom nav on tablet+ */
    .bottom-nav {
        display: none;
    }

    /* Adjust page content padding */
    .page-content {
        padding: var(--spacing-xl);
        padding-bottom: var(--spacing-xl);
    }

    /* Bottom actions become inline */
    .bottom-action {
        position: static;
        transform: none;
        box-shadow: none;
        border-top: none;
        padding: var(--spacing-lg) 0;
        max-width: 100%;
        background: transparent;
    }

    /* Center bottom action content on desktop */
    .bottom-action > * {
        max-width: 500px;
        margin: 0 auto;
    }

    /* Package Grid - 2 columns on tablet */
    .packages-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-lg);
    }

    /* Forms - wider inputs */
    .form-input,
    .form-textarea,
    .form-select {
        max-width: 500px;
    }

    /* Modal content wider */
    .modal-content {
        max-width: 600px;
    }

    /* Cards in grid */
    .address-card,
    .order-card {
        transition: transform var(--transition-fast), box-shadow var(--transition-fast);
    }

    .address-card:hover,
    .order-card:hover {
        transform: translateY(-2px);
        box-shadow: var(--shadow-lg);
    }

    /* Hero sections */
    .hero-section,
    .category-hero,
    .addresses-hero,
    .orders-hero,
    .profile-hero,
    .rate-hero,
    .order-hero {
        margin: -1rem -1rem 2rem -1rem;
        padding: 3rem 2rem;
    }

    /* Checkout sections side by side */
    .checkout-sections-wrapper {
        display: grid;
        grid-template-columns: 1fr 400px;
        gap: 2rem;
        align-items: start;
    }

    /* Package cards in row */
    .packages-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: var(--spacing-lg);
    }

    /* Login/Register forms centered */
    .login-container,
    .register-container {
        min-height: calc(100vh - 200px);
    }

    .login-form {
        max-width: 450px;
    }

    /* Stats grid */
    .stats-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--spacing-lg);
    }

    /* Profile sections in grid */
    .profile-sections-grid {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-lg);
    }
}

/* Desktop - 1024px and up */
@media (min-width: 1024px) {
    .app-container {
        max-width: 1280px;
    }

    .desktop-nav-container {
        max-width: 1280px;
    }

    /* Category Grid - 4 columns on desktop */
    .category-grid {
        grid-template-columns: repeat(4, 1fr);
        gap: var(--spacing-xl);
        padding: var(--spacing-xl);
    }

    /* Larger spacing */
    .page-content {
        padding: var(--spacing-2xl);
    }

    /* Hero sections bigger */
    .hero-section,
    .category-hero,
    .addresses-hero,
    .orders-hero,
    .profile-hero,
    .rate-hero,
    .order-hero {
        padding: 4rem 3rem;
    }

    /* Category hero title */
    .category-hero-title {
        font-size: 2.5rem;
    }

    .category-hero-icon {
        font-size: 5rem;
    }

    /* Package cards larger */
    .packages-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--spacing-xl);
    }

    /* Order cards in grid */
    .orders-grid {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-lg);
    }

    /* Profile grid 2 columns */
    .profile-sections-grid {
        gap: var(--spacing-xl);
    }

    /* Forms even wider */
    .form-input,
    .form-textarea,
    .form-select {
        max-width: 600px;
    }

    /* Modal even wider */
    .modal-content {
        max-width: 700px;
    }

    /* Add hover effects on desktop */
    .btn:hover {
        transform: translateY(-1px);
        box-shadow: var(--shadow-md);
    }

    .category-card:hover {
        transform: scale(1.05);
    }

    .package-card:hover {
        transform: translateY(-4px);
        box-shadow: var(--shadow-xl);
    }

    .touchable:hover {
        opacity: 0.9;
    }

    /* Checkout 3 column layout */
    .checkout-sections-wrapper {
        grid-template-columns: 2fr 1fr;
        gap: 3rem;
    }
}

/* Large Desktop - 1440px and up */
@media (min-width: 1440px) {
    .app-container {
        max-width: 1440px;
    }

    .desktop-nav-container {
        max-width: 1440px;
    }

    .category-grid {
        grid-template-columns: repeat(5, 1fr);
    }

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

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

/* Small mobile adjustments - 375px and down */
@media (max-width: 375px) {
    html {
        font-size: 14px;
    }

    .category-grid {
        grid-template-columns: 1fr 1fr;
        gap: 0.75rem;
        padding: 0.75rem;
    }

    .category-icon {
        font-size: 2.5rem;
    }

    .btn-lg {
        padding: 0.875rem 1.5rem;
        font-size: 1rem;
    }
}

/* Print styles */
@media print {
    .bottom-nav,
    .app-bar,
    .add-address-btn,
    .btn {
        display: none;
    }

    .app-container {
        box-shadow: none;
        max-width: 100%;
    }

    body {
        background: white;
    }
}