:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #16a34a;
    --secondary-dark: #15803d;
    --bg-light: #f0f9ff;
    --text-light: #374151;
    --text-dark: #f9fafb;
    --container-bg-light: #ffffff;
    --container-bg-dark: #1f2937;
    --input-bg-light: #f9fafb;
    --input-bg-dark: #374151;
    --border-light: #d1d5db;
    --border-dark: #4b5563;
    --result-bg-light: #eff6ff;
    --result-bg-dark: #1e3a8a;
    --result-border-light: #bfdbfe;
    --result-border-dark: #3b82f6;
    --error-bg-light: #fff7ed;
    --error-bg-dark: #7c2d12;
    --bac-low: #16a34a;
    --bac-medium: #f97316;
    --bac-high: #dc2626;
    --bac-very-high: #be123c;
    --toast-bg: #22c55e;
    --toast-bg-dark: #166534;
}

body {
    font-family: 'Inter', Arial, Helvetica, sans-serif;
    background-color: var(--bg-light);
    color: var(--text-light);
    transition: background-color 0.3s ease, color 0.3s ease;
}

body.dark-mode {
    background-color: #111827;
    color: var(--text-dark);
}

.calculator-container {
    background-color: var(--container-bg-light);
    padding: 1.5rem 2rem;
    border-radius: 16px; 
    box-shadow: 0 10px 35px rgba(0,0,0,0.08);
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

body.dark-mode .calculator-container {
    background-color: var(--container-bg-dark);
    box-shadow: 0 10px 35px rgba(0,0,0,0.2);
}

h1 { color: #1e3a8a; } 
h2 { color: #1e40af; } 
h3 { color: #1d4ed8; }

body.dark-mode h1 { color: #93c5fd; } 
body.dark-mode h2 { color: #60a5fa; } 
body.dark-mode h3 { color: #3b82f6; }

label {
    font-weight: 600;
    color: var(--text-light); 
    margin-bottom: 0.375rem;
    display: block;
    transition: color 0.3s ease;
}

body.dark-mode label {
    color: var(--text-dark);
}

[data-tooltip] {
    position: relative;
    cursor: help;
}

[data-tooltip]::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 125%;
    left: 50%;
    transform: translateX(-50%);
    background-color: #374151;
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    font-size: 0.875rem;
    white-space: nowrap;
    z-index: 10;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

body.dark-mode [data-tooltip]::after {
    background-color: #9ca3af;
    color: #111827;
}

[data-tooltip]:hover::after {
    opacity: 1;
}

@media (max-width: 768px) {
    [data-tooltip]::after {
        width: 200px;
        white-space: normal;
        text-align: center;
    }
}

select, input[type="number"], input[type="text"], input[type="time"] {
    width: 100%;
    padding: 0.85rem; 
    font-size: 1rem;
    border: 1px solid var(--border-light); 
    border-radius: 8px;
    margin-bottom: 1rem;
    box-sizing: border-box;
    background-color: var(--input-bg-light); 
    color: var(--text-light);
    transition: border-color 0.2s ease-in-out, box-shadow 0.2s ease-in-out, background-color 0.3s ease, color 0.3s ease;
}

body.dark-mode select, 
body.dark-mode input[type="number"], 
body.dark-mode input[type="text"], 
body.dark-mode input[type="time"] {
    background-color: var(--input-bg-dark);
    border-color: var(--border-dark);
    color: var(--text-dark);
}

select:focus, input[type="number"]:focus, input[type="text"]:focus, input[type="time"]:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.3);
    outline: none;
}

body.dark-mode select:focus, 
body.dark-mode input[type="number"]:focus, 
body.dark-mode input[type="text"]:focus, 
body.dark-mode input[type="time"]:focus {
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.5);
}

.submit-button {
    background-color: var(--primary-color);
    color: white;
    padding: 0.875rem 1.5rem;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1.125rem;
    font-weight: 600;
    display: block; 
    margin: 1.5rem auto;
    width: 100%;
    max-width: 360px;
    text-align: center;
    transition: background-color 0.3s ease, transform 0.1s ease;
}

.submit-button:hover {
    background-color: var(--primary-dark);
    transform: translateY(-1px);
}

.submit-button:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.5);
}

#resultArea {
    margin-top: 2rem;
    padding: 1.5rem;
    border: 1px solid var(--result-border-light); 
    background-color: var(--result-bg-light); 
    border-radius: 8px;
    line-height: 1.7;
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

body.dark-mode #resultArea {
    background-color: var(--result-bg-dark);
    border-color: var(--result-border-dark);
    color: var(--text-dark);
}

#resultArea h3 {
    margin-top: 0;
    color: #1e3a8a;
    border-bottom: 2px solid #93c5fd;
    padding-bottom: 0.75rem;
    margin-bottom: 1rem;
}

body.dark-mode #resultArea h3 {
    color: #93c5fd;
    border-bottom-color: #3b82f6;
}

.error-message {
    color: #c2410c;
    font-weight: 600;
    background-color: var(--error-bg-light);
    padding: 0.875rem 1.25rem;
    border-radius: 8px;
    border: 1px solid #fb923c;
    display: flex;
    align-items: center;
    transition: background-color 0.3s ease;
}

body.dark-mode .error-message {
    background-color: var(--error-bg-dark);
    color: #fdba74;
    border-color: #c2410c;
}

.spinner {
    width: 24px;
    height: 24px;
    border: 3px solid rgba(255,255,255,0.3);
    border-radius: 50%;
    border-top-color: #fff;
    animation: spin 1s ease-in-out infinite;
    margin-right: 8px;
}

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

.hidden { display: none !important; }

#explanationHeader { cursor: pointer; user-select: none; }
#explanationIcon { transition: transform 0.3s ease-in-out; }

.progress-container {
    background-color: #e5e7eb;
    border-radius: 9999px;
    height: 1rem;
    overflow: hidden;
    margin: 1rem 0;
    position: relative;
}

body.dark-mode .progress-container {
    background-color: #374151;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(to right, #22c55e, #3b82f6, #f97316, #dc2626);
    transition: width 0.5s ease-in-out;
    border-radius: 9999px;
}

.progress-text {
    position: absolute;
    width: 100%;
    text-align: center;
    font-weight: 600;
    font-size: 0.75rem;
    color: var(--text-light);
    mix-blend-mode: difference;
    top: 50%;
    transform: translateY(-50%);
}

body.dark-mode .progress-text {
    color: var(--text-dark);
}

.bac-low { color: var(--bac-low); font-weight: bold; } 
.bac-medium { color: var(--bac-medium); font-weight: bold; } 
.bac-high { color: var(--bac-high); font-weight: bold; } 
.bac-very-high { color: var(--bac-very-high); font-weight: bold; } 

.copy-button {
    background-color: #059669; 
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.875rem;
    font-weight: 500;
    margin-top: 1rem;
    transition: background-color 0.2s ease;
}

.copy-button:hover {
    background-color: #047857;
}

.copy-button:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(5, 150, 105, 0.5);
}

.toast-message {
    position: fixed; bottom: 20px; left: 50%;
    transform: translateX(-50%) translateY(100%); 
    background-color: var(--toast-bg); 
    color: white; 
    padding: 12px 22px;
    border-radius: 8px; 
    box-shadow: 0 4px 15px rgba(0,0,0,0.15);
    z-index: 1000; 
    opacity: 0;
    transition: opacity 0.3s ease-in-out, transform 0.3s ease-in-out, background-color 0.3s ease;
    font-size: 0.95rem;
}

body.dark-mode .toast-message {
    background-color: var(--toast-bg-dark);
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
}

.toast-message.show { 
    opacity: 1; 
    transform: translateX(-50%) translateY(0); 
}

.chart-container {
    width: 100%;
    height: 300px;
    margin: 1rem 0;
    position: relative;
}

.tabs {
    display: flex;
    margin: 1rem 0;
    border-bottom: 2px solid var(--border-light);
    transition: border-color 0.3s ease;
}

body.dark-mode .tabs {
    border-bottom-color: var(--border-dark);
}

.tab {
    padding: 0.75rem 1.25rem;
    cursor: pointer;
    font-weight: 500;
    transition: color 0.2s ease, border-color 0.2s ease;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
}

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

body.dark-mode .tab.active {
    color: #60a5fa;
    border-bottom-color: #60a5fa;
}

.tab-content {
    display: none;
    padding: 1rem 0;
}

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

.switch-container {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    margin: 1rem 0;
}

.switch-label {
    margin-right: 0.5rem;
    font-size: 0.875rem;
    user-select: none;
}

.switch {
    position: relative;
    display: inline-block;
    width: 48px;
    height: 24px;
}

.switch input { 
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ccc;
    transition: .4s;
    border-radius: 34px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 18px;
    width: 18px;
    left: 3px;
    bottom: 3px;
    background-color: white;
    transition: .4s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: var(--primary-color);
}

input:focus + .slider {
    box-shadow: 0 0 1px var(--primary-color);
}

input:checked + .slider:before {
    transform: translateX(24px);
}

.unit-switch {
    display: flex;
    justify-content: center;
    margin: 1rem 0;
    background-color: var(--input-bg-light);
    border-radius: 9999px;
    overflow: hidden;
    width: fit-content;
    border: 1px solid var(--border-light);
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

body.dark-mode .unit-switch {
    background-color: var(--input-bg-dark);
    border-color: var(--border-dark);
}

.unit-option {
    padding: 0.5rem 1rem;
    cursor: pointer;
    transition: background-color 0.3s ease;
    font-weight: 500;
    font-size: 0.875rem;
}

.unit-option.active {
    background-color: var(--primary-color);
    color: white;
}

/* Product Feed Styles */
.product-feed-container {
    background-color: var(--container-bg-light);
    padding: 1.5rem;
    border-radius: 16px;
    box-shadow: 0 10px 35px rgba(0,0,0,0.08);
    height: 100%;
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

body.dark-mode .product-feed-container {
    background-color: var(--container-bg-dark);
    box-shadow: 0 10px 35px rgba(0,0,0,0.2);
}

.product-card {
    border: 1px solid var(--border-light);
    border-radius: 12px;
    padding: 1rem;
    margin-bottom: 1rem;
    background-color: var(--input-bg-light);
    transition: box-shadow 0.2s ease-in-out, background-color 0.3s ease, border-color 0.3s ease;
    display: flex;
    flex-direction: column;
    justify-content: space-between; 
}

body.dark-mode .product-card {
    background-color: var(--input-bg-dark);
    border-color: var(--border-dark);
}

.product-card:hover {
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

body.dark-mode .product-card:hover {
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
}

.product-card img {
    max-width: 100%;
    height: 150px; 
    object-fit: contain; 
    margin-bottom: 0.75rem;
    border-radius: 8px;
}

.product-name {
    font-weight: 600;
    color: var(--text-light);
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
    line-height: 1.3;
    min-height: 2.6em; 
    transition: color 0.3s ease;
}

body.dark-mode .product-name {
    color: var(--text-dark);
}

.product-price-original {
    text-decoration: line-through;
    color: #9ca3af;
    font-size: 0.8rem;
}

.product-price-sale {
    color: var(--primary-color); 
    font-weight: bold;
    font-size: 1.1rem;
    margin-bottom: 0.75rem;
}

body.dark-mode .product-price-sale {
    color: #e879f9;
}

.product-link {
    display: inline-block;
    background-color: var(--secondary-color);
    color: white;
    text-align: center;
    padding: 0.6rem 1rem;
    border-radius: 6px;
    font-size: 0.875rem;
    font-weight: 500;
    text-decoration: none;
    transition: background-color 0.2s ease;
    margin-top: auto; 
}

.product-link:hover {
    background-color: var(--secondary-dark);
}

.product-link:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(192, 38, 211, 0.5);
}

/* Favorite drinks */
.favorites-container {
    margin-top: 1rem;
}

.favorite-drink {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 1rem;
    background-color: var(--input-bg-light);
    border-radius: 0.5rem;
    margin-bottom: 0.5rem;
    transition: background-color 0.3s ease;
}

body.dark-mode .favorite-drink {
    background-color: var(--input-bg-dark);
}

.favorite-drink:hover {
    background-color: #f3f4f6;
}

body.dark-mode .favorite-drink:hover {
    background-color: #4b5563;
}

.favorite-actions {
    display: flex;
    gap: 0.5rem;
}

.favorite-action {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--primary-color);
    transition: color 0.2s ease;
}

.favorite-action:hover {
    color: var(--primary-dark);
}

body.dark-mode .favorite-action {
    color: #60a5fa;
}

body.dark-mode .favorite-action:hover {
    color: #93c5fd;
}

/* EU countries legal limits */
.legal-limits-container {
    margin-top: 1rem;
    overflow-x: auto;
}

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

.legal-limits-table th, .legal-limits-table td {
    padding: 0.5rem;
    text-align: left;
    border-bottom: 1px solid var(--border-light);
    transition: border-color 0.3s ease;
}

body.dark-mode .legal-limits-table th, 
body.dark-mode .legal-limits-table td {
    border-bottom-color: var(--border-dark);
}

.legal-limits-table th {
    font-weight: 600;
    background-color: #f8fafc;
    transition: background-color 0.3s ease;
}

body.dark-mode .legal-limits-table th {
    background-color: #334155;
}

.legal-limits-table tr:nth-child(even) {
    background-color: #f1f5f9;
    transition: background-color 0.3s ease;
}

body.dark-mode .legal-limits-table tr:nth-child(even) {
    background-color: #1e293b;
}

.legal-limits-table tr:hover {
    background-color: #e0f2fe;
}

body.dark-mode .legal-limits-table tr:hover {
    background-color: #0f172a;
}

/* Food impact field */
.food-impact-container {
    margin-top: 1rem;
}

.food-impact-options {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 0.5rem;
}

.food-option {
    flex: 1;
    min-width: 150px;
    cursor: pointer;
    padding: 0.875rem;
    background-color: var(--input-bg-light);
    border: 1px solid var(--border-light);
    border-radius: 0.5rem;
    text-align: center;
    transition: background-color 0.3s ease, border-color 0.3s ease, transform 0.2s ease;
}

body.dark-mode .food-option {
    background-color: var(--input-bg-dark);
    border-color: var(--border-dark);
}

.food-option:hover {
    transform: translateY(-2px);
}

.food-option.selected {
    background-color: #e0f2fe;
    border-color: #38bdf8;
    font-weight: 500;
}

body.dark-mode .food-option.selected {
    background-color: #0c4a6e;
    border-color: #0ea5e9;
}

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

/* Expanded tooltips for mobile */
@media (max-width: 768px) {
    .calculator-container, .product-feed-container {
        padding: 1.25rem;
    }

    .tabs {
        flex-wrap: wrap;
    }

    .tab {
        flex-grow: 1;
        text-align: center;
        padding: 0.5rem;
        font-size: 0.875rem;
    }

    .food-option {
        min-width: 120px;
    }

    .unit-switch {
        width: 100%;
    }

    .unit-option {
        flex: 1;
        text-align: center;
    }

    /* Larger touch targets */
    .submit-button, .copy-button, .product-link, select, input, .food-option {
        min-height: 44px; /* Min height for touch targets */
    }

    /* Larger spacing for touch elements */
    .drink-section {
        margin-bottom: 1.5rem;
    }

    /* Improve legibility */
    label, .product-name {
        font-size: 1rem;
    }
}

@media (min-width: 769px) {
    .tooltip-container {
        display: flex;
        align-items: center;
    }

    .tooltip-icon {
        margin-left: 0.5rem;
        display: flex;
        align-items: center;
    }
}