/* CSS Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Scheme */
    --primary-color: #2563eb;
    --secondary-color: #64748b;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    
    /* Light Theme */
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    
    /* Weather Themes */
    --sunny-bg: linear-gradient(135deg, #fbbf24 0%, #f59e0b 100%);
    --cloudy-bg: linear-gradient(135deg, #94a3b8 0%, #64748b 100%);
    --rainy-bg: linear-gradient(135deg, #3b82f6 0%, #1e40af 100%);
    --snowy-bg: linear-gradient(135deg, #e2e8f0 0%, #cbd5e1 100%);
    --night-bg: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Transitions */
    --transition: all 0.2s ease-in-out;
}

/* Dark Theme */
[data-theme="dark"] {
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
}

/* Auto Theme (prefers-color-scheme) */
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --bg-color: #0f172a;
        --card-bg: #1e293b;
        --text-primary: #f1f5f9;
        --text-secondary: #94a3b8;
        --border-color: #334155;
        --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
    }
}

/* Base Styles */
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    transition: var(--transition);
    min-height: 100vh;
}

/* Weather Background Themes */
.app.sunny { background: var(--sunny-bg); }
.app.cloudy { background: var(--cloudy-bg); }
.app.rainy { background: var(--rainy-bg); }
.app.snowy { background: var(--snowy-bg); }
.app.night { background: var(--night-bg); }

.app {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-md);
    min-height: 100vh;
    transition: var(--transition);
}

/* Screen Reader Only */
.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;
}

/* Header */
.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-xl);
    padding: var(--spacing-md);
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
}

.header h1 {
    font-size: 1.875rem;
    font-weight: 700;
    color: var(--primary-color);
}

.controls {
    display: flex;
    gap: var(--spacing-sm);
}

.settings-btn, .temp-toggle {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--card-bg);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.875rem;
}

.settings-btn:hover, .temp-toggle:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-1px);
}

/* Search Section */
.search-section {
    margin-bottom: var(--spacing-xl);
    position: relative;
}

.search-container {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
}

.search-input {
    flex: 1;
    padding: var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    background: var(--card-bg);
    color: var(--text-primary);
    font-size: 1rem;
    transition: var(--transition);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.location-btn {
    padding: var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    background: var(--card-bg);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 1.25rem;
}

.location-btn:hover {
    background: var(--primary-color);
    color: white;
    transform: scale(1.05);
}

/* Search Suggestions */
.search-suggestions {
    position: absolute;
    top: 100%;
    left: 0;
    right: 60px;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow);
    z-index: 100;
    max-height: 200px;
    overflow-y: auto;
    display: none;
}

.search-suggestions.show {
    display: block;
}

.suggestion-item {
    padding: var(--spacing-md);
    cursor: pointer;
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition);
}

.suggestion-item:hover, .suggestion-item.selected {
    background: var(--primary-color);
    color: white;
}

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

/* Loading Spinner */
.loading {
    text-align: center;
    padding: var(--spacing-xl);
    display: none;
}

.loading.show {
    display: block;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-md);
}

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

/* Error Message */
.error {
    text-align: center;
    padding: var(--spacing-xl);
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    border-left: 4px solid var(--error-color);
    margin-bottom: var(--spacing-xl);
    display: none;
}

.error.show {
    display: block;
}

.error p {
    color: var(--error-color);
    margin-bottom: var(--spacing-md);
}

.retry-btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    background: var(--error-color);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
}

.retry-btn:hover {
    background: #dc2626;
    transform: translateY(-1px);
}

/* Weather Content */
.weather-content {
    display: none;
}

.weather-content.show {
    display: block;
}

/* Current Weather Card */
.current-weather {
    background: var(--card-bg);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow);
    backdrop-filter: blur(10px);
}

.current-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: var(--spacing-lg);
}

.location-info h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.location-info p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.share-btn {
    padding: var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: transparent;
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 1.25rem;
}

.share-btn:hover {
    background: var(--primary-color);
    color: white;
    transform: scale(1.1);
}

.current-main {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
}

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

.weather-icon {
    width: 80px;
    height: 80px;
    object-fit: contain;
}

.temp-info {
    display: flex;
    flex-direction: column;
}

.temperature {
    font-size: 3rem;
    font-weight: 700;
    line-height: 1;
    color: var(--primary-color);
}

.condition {
    font-size: 1.125rem;
    color: var(--text-secondary);
    text-transform: capitalize;
}

.weather-details {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: var(--spacing-md);
}

.detail-item {
    display: flex;
    flex-direction: column;
    text-align: center;
    padding: var(--spacing-sm);
    background: rgba(37, 99, 235, 0.05);
    border-radius: var(--radius-md);
}

.detail-item .label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: var(--spacing-xs);
}

.sun-times {
    display: flex;
    justify-content: space-around;
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
}

.sun-time {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
}

.sun-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* Hourly Section */
.hourly-section {
    background: var(--card-bg);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
}

.section-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
}

.toggle-chart {
    padding: var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: transparent;
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
}

.toggle-chart:hover {
    background: var(--primary-color);
    color: white;
}

.chart-container {
    overflow-x: auto;
    padding: var(--spacing-md) 0;
}

#hourlyChart {
    display: block;
    max-width: 100%;
    height: auto;
}

/* Forecast Section */
.forecast-section {
    background: var(--card-bg);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow);
}

.forecast-section h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
}

.forecast-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
}

.forecast-item {
    padding: var(--spacing-lg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    text-align: center;
    transition: var(--transition);
}

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

.forecast-date {
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--primary-color);
}

.forecast-icon {
    width: 48px;
    height: 48px;
    margin: var(--spacing-sm) auto;
    display: block;
}

.forecast-temps {
    display: flex;
    justify-content: space-between;
    margin: var(--spacing-sm) 0;
    font-weight: 600;
}

.forecast-condition {
    font-size: 0.875rem;
    color: var(--text-secondary);
    text-transform: capitalize;
}

/* Last Updated */
.last-updated {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.75rem;
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
}

.modal.show {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    max-width: 400px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    transform: scale(0.9);
    transition: var(--transition);
}

.modal.show .modal-content {
    transform: scale(1);
}

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

.modal-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
}

.close-btn {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    transition: var(--transition);
}

.close-btn:hover {
    color: var(--text-primary);
    transform: scale(1.1);
}

.setting-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
}

.setting-item label {
    font-weight: 500;
}

.setting-item select,
.setting-item input[type="checkbox"] {
    padding: var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--card-bg);
    color: var(--text-primary);
}

/* Responsive Design */
@media (max-width: 768px) {
    .app {
        padding: var(--spacing-sm);
    }
    
    .header {
        flex-direction: column;
        gap: var(--spacing-md);
        text-align: center;
    }
    
    .header h1 {
        font-size: 1.5rem;
    }
    
    .current-main {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .temp-display {
        justify-content: center;
        margin-bottom: var(--spacing-lg);
    }
    
    .weather-details {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .sun-times {
        flex-direction: column;
        gap: var(--spacing-md);
    }
    
    .forecast-container {
        grid-template-columns: 1fr;
    }
    
    .search-suggestions {
        right: 0;
    }
}

@media (max-width: 480px) {
    .weather-details {
        grid-template-columns: 1fr;
    }
    
    .temperature {
        font-size: 2.5rem;
    }
    
    .weather-icon {
        width: 60px;
        height: 60px;
    }
}

/* Focus Styles for Accessibility */
button:focus,
input:focus,
select:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* High Contrast Mode Support */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000000;
        --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.5);
    }
}

/* Reduced Motion Support */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    .spinner {
        animation: none;
        border: 4px solid var(--primary-color);
    }
}