/* CSS Variables for consistent theming */
:root {
    --primary-color: #7868E6;
    --secondary-color: #B8B5FF;
    --accent-color: #FFB4B4;
    --light-blue: #E4FBFF;
    --light-gray: #EDEEF7;
    --white: #FFFFFF;
    --black: #333333;
    --success: #4CAF50;
    --warning: #FF9800;
    --error: #F44336;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    --border-radius: 8px;
    --transition: all 0.3s ease;
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

/* Paper Texture Background */
body {
    background-color: var(--light-gray);
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(120, 104, 230, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(184, 181, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 40% 80%, rgba(255, 180, 180, 0.1) 0%, transparent 50%);
    background-attachment: fixed;
    font-family: var(--font-family);
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Reset and Base Styles */
* {
    box-sizing: border-box;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header Styles */
.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    padding: 1rem 0;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header__title {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    margin: 0 0 1rem 0;
    font-weight: 600;
}

.header__icon {
    font-size: 2rem;
}

.header__nav {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.nav-btn {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: var(--white);
    padding: 0.75rem 1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    backdrop-filter: blur(10px);
}

.nav-btn:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
}

.nav-btn.active {
    background: var(--white);
    color: var(--primary-color);
    font-weight: 600;
}

.nav-btn__icon {
    font-size: 1.2rem;
}

/* Main Content */
.main {
    flex: 1;
    padding: 2rem 0;
}

/* Tab Content */
.tab-content {
    display: none;
    animation: fadeIn 0.3s ease;
}

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

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

.tab-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.tab-header h2 {
    margin: 0;
    color: var(--primary-color);
    font-size: 1.8rem;
}

/* Counter Styles */
.counter, .shopping-counter {
    background: var(--white);
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    font-weight: 600;
    color: var(--primary-color);
}

/* Add Item Form */
.add-item-form {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.add-item-input {
    flex: 1;
    min-width: 200px;
    padding: 1rem;
    border: 2px solid var(--light-gray);
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
}

.add-item-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(120, 104, 230, 0.2);
}

.add-item-price {
    width: 120px;
    padding: 1rem;
    border: 2px solid var(--light-gray);
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
}

.add-item-price:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(120, 104, 230, 0.2);
}

.add-item-btn {
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: var(--white);
    border: none;
    border-radius: var(--border-radius);
    font-size: 1.5rem;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.add-item-btn:hover {
    background: var(--secondary-color);
    transform: scale(1.05);
}

/* Checklist Styles */
.checklist-container {
    background: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    margin-bottom: 2rem;
}

.checklist-items {
    min-height: 200px;
    padding: 1rem;
}

.checklist-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    border-radius: var(--border-radius);
    margin-bottom: 0.5rem;
    background: var(--light-gray);
    transition: var(--transition);
    cursor: grab;
    user-select: none;
    position: relative;
}

.checklist-item:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow);
}

.checklist-item.dragging {
    opacity: 0.5;
    cursor: grabbing;
}

.checklist-item.completed {
    opacity: 0.7;
    text-decoration: line-through;
}

.checklist-item__checkbox {
    width: 24px;
    height: 24px;
    border: 2px solid var(--primary-color);
    border-radius: 4px;
    cursor: pointer;
    position: relative;
    flex-shrink: 0;
}

.checklist-item__checkbox.checked {
    background: var(--primary-color);
}

.checklist-item__checkbox.checked::after {
    content: '✓';
    color: var(--white);
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 14px;
    font-weight: bold;
}

.checklist-item__content {
    flex: 1;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.checklist-item__name {
    font-weight: 500;
    color: var(--black);
}

.checklist-item__price {
    color: var(--primary-color);
    font-weight: 600;
}

.checklist-item__actions {
    display: flex;
    gap: 0.5rem;
}

.checklist-item__delete {
    background: var(--error);
    color: var(--white);
    border: none;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.checklist-item__delete:hover {
    transform: scale(1.1);
}

.checklist-item__drag-handle {
    color: var(--primary-color);
    cursor: grab;
    font-size: 1.2rem;
}

/* Button Styles */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
}

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

.btn--primary:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

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

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

.checklist-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Budget Styles */
.budget-summary {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.budget-card {
    background: var(--white);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    text-align: center;
}

.budget-card h3 {
    margin: 0 0 1rem 0;
    color: var(--primary-color);
    font-size: 1.1rem;
}

.budget-input-group {
    display: flex;
    align-items: center;
    background: var(--light-gray);
    border-radius: var(--border-radius);
    overflow: hidden;
}

.currency {
    padding: 1rem;
    background: var(--primary-color);
    color: var(--white);
    font-weight: 600;
}

.budget-input {
    flex: 1;
    padding: 1rem;
    border: none;
    font-size: 1.2rem;
    font-weight: 600;
    text-align: center;
    background: transparent;
}

.budget-input:focus {
    outline: none;
}

.budget-value {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary-color);
}

.budget-progress {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.progress-bar {
    flex: 1;
    height: 20px;
    background: var(--light-gray);
    border-radius: 10px;
    overflow: hidden;
    position: relative;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--success), var(--warning));
    transition: width 0.3s ease;
    border-radius: 10px;
}

.progress-text {
    font-weight: 600;
    color: var(--primary-color);
    min-width: 40px;
}

.budget-items-list {
    background: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 1rem;
}

.budget-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--light-gray);
}

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

.budget-item__name {
    font-weight: 500;
}

.budget-item__price {
    color: var(--primary-color);
    font-weight: 600;
}

/* Compare Styles */
.compare-search {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.search-input {
    flex: 1;
    min-width: 200px;
    padding: 1rem;
    border: 2px solid var(--light-gray);
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(120, 104, 230, 0.2);
}

.compare-filters {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.filter-select {
    padding: 0.75rem;
    border: 2px solid var(--light-gray);
    border-radius: var(--border-radius);
    font-size: 1rem;
    background: var(--white);
    cursor: pointer;
    transition: var(--transition);
}

.filter-select:focus {
    outline: none;
    border-color: var(--primary-color);
}

.compare-results {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1rem;
}

.compare-item {
    background: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 1.5rem;
    transition: var(--transition);
}

.compare-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.15);
}

.compare-item__name {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--black);
    margin-bottom: 0.5rem;
}

.compare-item__category {
    color: var(--primary-color);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.compare-item__prices {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.compare-price {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem;
    background: var(--light-gray);
    border-radius: 4px;
}

.compare-price__store {
    font-weight: 500;
}

.compare-price__value {
    color: var(--primary-color);
    font-weight: 600;
}

.compare-price--best {
    background: var(--success);
    color: var(--white);
}

.compare-price--best .compare-price__value {
    color: var(--white);
}

/* Shopping Mode Styles */
.shopping-progress {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.shopping-location {
    background: var(--white);
    padding: 1rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
    text-align: center;
}

.location-info {
    margin-top: 1rem;
    padding: 1rem;
    background: var(--light-blue);
    border-radius: var(--border-radius);
    text-align: left;
}

.location-info h4 {
    margin: 0 0 0.5rem 0;
    color: var(--primary-color);
}

.shopping-items {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.shopping-item {
    background: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 1.5rem;
    transition: var(--transition);
}

.shopping-item.completed {
    background: var(--success);
    color: var(--white);
}

.shopping-item__header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.shopping-item__checkbox {
    width: 30px;
    height: 30px;
    border: 3px solid var(--primary-color);
    border-radius: 6px;
    cursor: pointer;
    position: relative;
    flex-shrink: 0;
}

.shopping-item__checkbox.checked {
    background: var(--primary-color);
}

.shopping-item__checkbox.checked::after {
    content: '✓';
    color: var(--white);
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 18px;
    font-weight: bold;
}

.shopping-item__name {
    font-size: 1.2rem;
    font-weight: 600;
    flex: 1;
}

.shopping-item__price {
    color: var(--primary-color);
    font-weight: 600;
    font-size: 1.1rem;
}

.shopping-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Footer */
.footer {
    background: var(--primary-color);
    color: var(--white);
    text-align: center;
    padding: 1rem 0;
    margin-top: auto;
}

.footer p {
    margin: 0;
    font-size: 0.9rem;
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    color: var(--white);
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top: 4px solid var(--white);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 1rem;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1001;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.toast {
    background: var(--white);
    padding: 1rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    border-left: 4px solid var(--primary-color);
    animation: slideIn 0.3s ease;
    max-width: 300px;
}

.toast.success {
    border-left-color: var(--success);
}

.toast.error {
    border-left-color: var(--error);
}

.toast.warning {
    border-left-color: var(--warning);
}

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

/* Utility Classes */
.hidden {
    display: none !important;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }
    
    .header__title {
        font-size: 1.2rem;
    }
    
    .header__nav {
        justify-content: center;
    }
    
    .nav-btn {
        flex: 1;
        min-width: 80px;
        justify-content: center;
    }
    
    .nav-btn__text {
        display: none;
    }
    
    .tab-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .add-item-form {
        flex-direction: column;
    }
    
    .add-item-input,
    .add-item-price {
        width: 100%;
    }
    
    .budget-summary {
        grid-template-columns: 1fr;
    }
    
    .compare-search {
        flex-direction: column;
    }
    
    .compare-filters {
        flex-direction: column;
    }
    
    .shopping-items {
        grid-template-columns: 1fr;
    }
    
    .checklist-actions,
    .shopping-actions {
        flex-direction: column;
    }
    
    .toast-container {
        left: 20px;
        right: 20px;
    }
    
    .toast {
        max-width: none;
    }
}

@media (max-width: 480px) {
    .main {
        padding: 1rem 0;
    }
    
    .tab-header h2 {
        font-size: 1.5rem;
    }
    
    .checklist-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }
    
    .checklist-item__content {
        width: 100%;
    }
    
    .budget-card {
        padding: 1rem;
    }
    
    .compare-item {
        padding: 1rem;
    }
    
    .shopping-item {
        padding: 1rem;
    }
}

/* Print Styles */
@media print {
    .header__nav,
    .add-item-form,
    .checklist-actions,
    .shopping-actions,
    .loading-overlay,
    .toast-container {
        display: none !important;
    }
    
    body {
        background: white !important;
    }
    
    .tab-content {
        display: block !important;
    }
    
    .checklist-item,
    .budget-card,
    .compare-item,
    .shopping-item {
        break-inside: avoid;
    }
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
    :root {
        --primary-color: #000000;
        --secondary-color: #666666;
        --light-gray: #f0f0f0;
        --shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
    }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}