:root {
    --primary-color: #4CAF50;
    --primary-light: #81C784;
    --secondary-color: #FF9800;
    --text-primary: #2C3E50;
    --text-secondary: #7F8C8D;
    --background: #F5F7FA;
    --card-background: #FFFFFF;
    --border-color: #E0E0E0;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: var(--background);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    color: var(--text-primary);
}

.app-container {
    width: 100%;
    max-width: 1200px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    padding: 2rem;
}

.app-header {
    text-align: center;
    margin-bottom: 3rem;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.logo i {
    font-size: 2.5rem;
    color: var(--primary-color);
}

.logo h1 {
    font-size: 2.5rem;
    color: var(--text-primary);
    font-weight: 700;
}

.tagline {
    color: var(--text-secondary);
    font-size: 1.2rem;
}

.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.upload-section {
    width: 100%;
    max-width: 600px;
    margin-bottom: 2rem;
}

.upload-box {
    border: 2px dashed var(--border-color);
    border-radius: 16px;
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    background-color: var(--card-background);
    box-shadow: var(--shadow);
}

.upload-box:hover {
    border-color: var(--primary-color);
    transform: translateY(-2px);
}

.upload-box.dragover {
    border-color: var(--primary-color);
    background-color: rgba(76, 175, 80, 0.05);
}

.upload-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.upload-icon-container {
    width: 80px;
    height: 80px;
    background-color: rgba(76, 175, 80, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1rem;
}

.upload-icon-container i {
    font-size: 2.5rem;
    color: var(--primary-color);
}

.upload-content h2 {
    font-size: 1.8rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.or-divider {
    position: relative;
    color: var(--text-secondary);
    margin: 1rem 0;
}

.or-divider::before,
.or-divider::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 100px;
    height: 1px;
    background-color: var(--border-color);
}

.or-divider::before {
    right: 100%;
    margin-right: 1rem;
}

.or-divider::after {
    left: 100%;
    margin-left: 1rem;
}

.upload-btn {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 1rem 2rem;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1.1rem;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

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

.upload-hint {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 1rem;
}

.results-section {
    width: 100%;
    max-width: 800px;
    margin-top: 2rem;
}

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

.results-header h2 {
    font-size: 1.8rem;
    color: var(--text-primary);
}

.total-calories {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem;
    background-color: var(--card-background);
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.calories-icon {
    width: 50px;
    height: 50px;
    background-color: rgba(255, 152, 0, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.calories-icon i {
    font-size: 1.5rem;
    color: var(--secondary-color);
}

.calories-info h3 {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
}

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

.food-items {
    display: grid;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.food-item {
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    background-color: var(--card-background);
    transition: var(--transition);
    position: relative;
    box-shadow: var(--shadow);
}

.food-item.primary {
    border-left: 4px solid var(--primary-color);
    background-color: rgba(76, 175, 80, 0.05);
}

.food-item:not(.primary) {
    border-left: 4px solid var(--secondary-color);
    background-color: rgba(255, 152, 0, 0.05);
    opacity: 0.9;
}

.food-item-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.food-item h3 {
    font-size: 1.2rem;
    color: var(--text-primary);
    margin: 0;
}

.primary-toggle {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    user-select: none;
    padding: 0.5rem;
    border-radius: 6px;
    transition: var(--transition);
}

.primary-toggle:hover {
    background-color: rgba(0, 0, 0, 0.05);
}

.primary-toggle input[type="checkbox"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
    accent-color: var(--primary-color);
}

.serving-size-container {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.serving-size-select {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--card-background);
    font-size: 1rem;
    color: var(--text-primary);
    cursor: pointer;
    min-width: 200px;
    transition: var(--transition);
}

.serving-size-select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(76, 175, 80, 0.2);
}

.non-primary-note {
    color: var(--secondary-color);
    font-size: 0.9rem;
    font-style: italic;
    margin-top: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.non-primary-note i {
    font-size: 1rem;
}

.loading {
    text-align: center;
    padding: 3rem;
    display: none;
}

.loading.active {
    display: block;
}

.loading-spinner {
    width: 60px;
    height: 60px;
    border: 5px solid rgba(76, 175, 80, 0.1);
    border-top: 5px solid var(--primary-color);
    border-radius: 50%;
    margin: 0 auto 1.5rem;
    animation: spin 1s linear infinite;
}

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

.loading p {
    color: var(--text-primary);
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

.loading-subtext {
    color: var(--text-secondary);
    font-size: 1rem;
}

.error {
    color: #f44336;
    text-align: center;
    padding: 1rem;
    background-color: #ffebee;
    border-radius: 8px;
    margin-top: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.results-footer {
    text-align: center;
    margin-top: 2rem;
    padding: 1rem;
    background-color: rgba(0, 0, 0, 0.02);
    border-radius: 8px;
}

.disclaimer {
    color: var(--text-secondary);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.app-footer {
    text-align: center;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.food-details {
    display: grid;
    gap: 1.5rem;
    margin-top: 1rem;
}

.quantity-control {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.quantity-input {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.quantity-btn {
    width: 32px;
    height: 32px;
    border: 1px solid var(--border-color);
    background-color: var(--card-background);
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    font-size: 1.2rem;
    color: var(--text-primary);
}

.quantity-btn:hover {
    background-color: var(--primary-light);
    color: white;
    border-color: var(--primary-color);
}

.quantity-value {
    width: 60px;
    height: 32px;
    text-align: center;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    color: var(--text-primary);
}

.quantity-value:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(76, 175, 80, 0.2);
}

.nutrition-facts {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    padding: 1rem;
    background-color: rgba(0, 0, 0, 0.02);
    border-radius: 8px;
}

.nutrition-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.5rem;
    border-radius: 6px;
    transition: var(--transition);
}

.nutrition-item:hover {
    background-color: rgba(0, 0, 0, 0.03);
}

.nutrition-item i {
    font-size: 1.2rem;
    color: var(--primary-color);
}

.nutrition-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.nutrition-value {
    font-weight: 600;
    color: var(--text-primary);
}

.nutrition-value.calories {
    color: var(--secondary-color);
}

.nutrition-value.protein {
    color: #2196F3;
}

.nutrition-value.carbs {
    color: #4CAF50;
}

.nutrition-value.fat {
    color: #FF9800;
}

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

    .results-header {
        flex-direction: column;
        gap: 1rem;
    }

    .total-calories {
        width: 100%;
    }

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

    .nutrition-facts {
        grid-template-columns: 1fr 1fr;
    }
    
    .quantity-control {
        flex-direction: column;
        align-items: flex-start;
    }
}