/* ===================================
   CSS Variables for Theming
   =================================== */
:root {
    /* Colors */
    --color-primary: #2196F3;
    --color-primary-dark: #1976D2;
    --color-primary-light: #BBDEFB;
    --color-secondary: #757575;
    --color-text: #212121;
    --color-text-light: #757575;
    --color-background: #FFFFFF;
    --color-background-alt: #F5F5F5;
    --color-border: #E0E0E0;
    --color-error: #F44336;
    --color-success: #4CAF50;
    --color-warning: #FF9800;
    --color-grey-line: #BDBDBD;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-xxl: 3rem;
    
    /* Typography */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    --font-size-base: 16px;
    --font-size-sm: 14px;
    --font-size-lg: 18px;
    --font-size-xl: 24px;
    --font-size-xxl: 32px;
    --line-height: 1.5;
    
    /* Breakpoints */
    --breakpoint-mobile: 768px;
    --breakpoint-tablet: 1024px;
    
    /* Touch Targets */
    --touch-target-min: 44px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
    
    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.12);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 20px rgba(0, 0, 0, 0.15);
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
}

/* ===================================
   Base Styles
   =================================== */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: var(--font-size-base);
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: var(--line-height);
    color: var(--color-text);
    background-color: var(--color-background-alt);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===================================
   Container
   =================================== */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ===================================
   Header
   =================================== */
.header {
    background-color: var(--color-background);
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-lg) 0;
    box-shadow: var(--shadow-sm);
}

.header-row {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: var(--spacing-md);
}

.header-title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
    color: var(--color-text);
}

.version-badge {
    font-size: 10px;
    font-family: monospace;
    color: var(--color-text-light);
    background-color: var(--color-background-alt);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
    white-space: nowrap;
    opacity: 0.7;
    transition: opacity var(--transition-fast);
}

.version-badge:hover {
    opacity: 1;
}

.database-date-range {
    font-size: var(--font-size-sm);
    color: var(--color-text-light);
    margin-bottom: var(--spacing-sm);
    font-style: italic;
}

.time-range-display {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    font-size: var(--font-size-sm);
}

.time-range-label {
    color: var(--color-text-light);
    font-weight: 500;
}

.time-range-value {
    color: var(--color-text);
    font-weight: 600;
}

.time-period-badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-sm);
    background-color: var(--color-primary-light);
    color: var(--color-primary-dark);
    border-radius: var(--radius-sm);
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
}

/* ===================================
   Navigation
   =================================== */
.navigation {
    background-color: var(--color-background);
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-md) 0;
}

.navigation .container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

/* ===================================
   Filter Bar (BI-style toolbar)
   =================================== */
.filter-bar {
    display: flex;
    flex-wrap: wrap;
    align-items: flex-end;
    gap: var(--spacing-lg);
    padding: var(--spacing-md) var(--spacing-lg);
    background-color: var(--color-background);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
}

.filter-section {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.filter-section-label {
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    color: var(--color-text-light);
}

/* Vertical rule separating toolbar sections */
.filter-divider {
    align-self: stretch;
    width: 1px;
    margin: 2px 0;
    background-color: var(--color-border);
}

/* Control sizing token shared across toolbar controls for alignment */
:root {
    --control-height: 40px;
}

/* ---- Segmented control (quick ranges) ---- */
.segmented {
    display: inline-flex;
    flex-wrap: wrap;
    gap: 2px;
    padding: 3px;
    background-color: var(--color-background-alt);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    width: fit-content;
    max-width: 100%;
}

.segmented-btn {
    min-height: var(--control-height);
    min-width: 52px;
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-text-light);
    background-color: transparent;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: color var(--transition-fast), background-color var(--transition-fast);
    white-space: nowrap;
}

.segmented-btn:hover {
    color: var(--color-text);
    background-color: var(--color-primary-light);
}

/* Selected state — filled pill, visually distinct from hover */
.segmented-btn.active {
    color: var(--color-background);
    background-color: var(--color-primary);
    box-shadow: var(--shadow-sm);
}

.segmented-btn.active:hover {
    color: var(--color-background);
    background-color: var(--color-primary-dark);
}

.segmented-btn:active {
    transform: translateY(1px);
}

/* ---- Custom range row (From / arrow / To / Apply) ---- */
.custom-range-row {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.range-arrow {
    color: var(--color-text-light);
    font-weight: 700;
}

/* Highlight the custom inputs when custom range is the active mode */
.filter-section--custom.is-active .datetime-input {
    border-color: var(--color-primary);
}

.datetime-input {
    min-height: var(--control-height);
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    font-family: var(--font-family);
    color: var(--color-text);
    background-color: var(--color-background);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.datetime-input:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

/* ---- Granularity dropdown ---- */
.select-wrap {
    position: relative;
    display: inline-flex;
}

.granularity-select {
    appearance: none;
    -webkit-appearance: none;
    min-height: var(--control-height);
    padding: var(--spacing-sm) calc(var(--spacing-xl) + 2px) var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    font-weight: 600;
    font-family: var(--font-family);
    color: var(--color-text);
    background-color: var(--color-background);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.granularity-select:hover {
    border-color: var(--color-primary);
}

.granularity-select:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

/* Custom chevron for the select */
.select-wrap::after {
    content: "";
    position: absolute;
    top: 50%;
    right: 14px;
    width: 0;
    height: 0;
    transform: translateY(-25%);
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-top: 6px solid var(--color-text-light);
    pointer-events: none;
}

/* ---- Apply button ---- */
.apply-button {
    min-height: var(--control-height);
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-background);
    background-color: var(--color-primary);
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: background-color var(--transition-fast);
    box-shadow: var(--shadow-sm);
}

.apply-button:hover {
    background-color: var(--color-primary-dark);
}

.apply-button:active {
    transform: translateY(1px);
}

/* ---- Filter status line (single source of truth) ---- */
.filter-status {
    margin-top: var(--spacing-md);
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-primary-dark);
    background-color: var(--color-primary-light);
    border-radius: var(--radius-sm);
    display: inline-block;
}

.filter-status::before {
    content: "▸ ";
    color: var(--color-primary);
}

/* Drill Navigation */
.drill-navigation {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--color-border);
}

.nav-button {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    min-height: var(--touch-target-min);
    min-width: var(--touch-target-min);
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-background);
    background-color: var(--color-primary);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: background-color var(--transition-fast);
    box-shadow: var(--shadow-sm);
}

.nav-button:hover:not(:disabled) {
    background-color: var(--color-primary-dark);
}

.nav-button:active:not(:disabled) {
    transform: translateY(1px);
}

.nav-button:disabled {
    background-color: var(--color-secondary);
    cursor: not-allowed;
    opacity: 0.5;
}

.button-icon {
    font-size: var(--font-size-lg);
    line-height: 1;
}

/* ===================================
   Main Content
   =================================== */
.main-content {
    padding: var(--spacing-xl) 0;
    min-height: 60vh;
}

/* ===================================
   Loading Indicator
   =================================== */
.loading-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xxl);
    text-align: center;
}

.spinner {
    width: 48px;
    height: 48px;
    border: 4px solid var(--color-border);
    border-top-color: var(--color-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

.loading-text {
    margin-top: var(--spacing-md);
    color: var(--color-text-light);
    font-size: var(--font-size-sm);
}

/* ===================================
   Error Message
   =================================== */
.error-message {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    background-color: #FFEBEE;
    border: 1px solid var(--color-error);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
}

.error-icon {
    font-size: var(--font-size-xxl);
    flex-shrink: 0;
}

.error-content {
    flex: 1;
}

.error-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--color-error);
    margin-bottom: var(--spacing-sm);
}

.error-description {
    color: var(--color-text);
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-sm);
}

.error-retry-btn {
    min-height: var(--touch-target-min);
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-background);
    background-color: var(--color-error);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: background-color var(--transition-fast);
}

.error-retry-btn:hover {
    background-color: #D32F2F;
}

/* ===================================
   Empty State
   =================================== */
.empty-state {
    text-align: center;
    padding: var(--spacing-xxl);
}

.empty-icon {
    font-size: 64px;
    margin-bottom: var(--spacing-md);
}

.empty-title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: var(--spacing-sm);
}

.empty-description {
    color: var(--color-text-light);
    font-size: var(--font-size-sm);
}

/* ===================================
   Data Availability Notice
   =================================== */
.data-notice {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: #7a5b00;
    background-color: #FFF8E1;
    border: 1px solid var(--color-warning);
    border-radius: var(--radius-sm);
}

.data-notice::before {
    content: "ⓘ";
    font-weight: 700;
    color: var(--color-warning);
    flex-shrink: 0;
}

/* ===================================
   Graphs Container
   =================================== */
.graphs-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

.chart-wrapper {
    background-color: var(--color-background);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
}

.chart-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: var(--spacing-md);
}

.chart-canvas {
    width: 100%;
    height: auto;
}

/* ===================================
   Footer
   =================================== */
.footer {
    background-color: var(--color-background);
    border-top: 1px solid var(--color-border);
    padding: var(--spacing-lg) 0;
    margin-top: var(--spacing-xxl);
}

.footer-text {
    text-align: center;
    color: var(--color-text-light);
    font-size: var(--font-size-sm);
}

/* ===================================
   Responsive Design - Mobile First
   =================================== */

/* Mobile (< 768px) - Base styles above are mobile-first */
@media (max-width: 767px) {
    .header-title {
        font-size: var(--font-size-lg);
    }
    
    .time-range-display {
        font-size: 12px;
    }
    
    /* Stack toolbar sections vertically on narrow screens */
    .filter-bar {
        flex-direction: column;
        align-items: stretch;
        gap: var(--spacing-md);
        padding: var(--spacing-md);
    }
    
    .filter-divider {
        display: none;
    }
    
    .segmented {
        width: 100%;
    }
    
    .segmented-btn {
        flex: 1 1 auto;
        min-width: 0;
        text-align: center;
    }
    
    .custom-range-row {
        width: 100%;
    }
    
    .custom-range-row .datetime-input {
        flex: 1 1 40%;
        min-width: 0;
    }
    
    .granularity-select {
        width: 100%;
    }
    
    .drill-navigation {
        flex-direction: column;
    }
    
    .nav-button {
        width: 100%;
        justify-content: center;
    }
    
    .chart-wrapper {
        padding: var(--spacing-md);
    }
    
    .chart-title {
        font-size: var(--font-size-base);
    }
}

/* Tablet (768px - 1024px) */
@media (min-width: 768px) and (max-width: 1023px) {
    .container {
        padding: 0 var(--spacing-lg);
    }
    
    .drill-navigation {
        justify-content: center;
    }
}

/* Desktop (> 1024px) */
@media (min-width: 1024px) {
    .container {
        padding: 0 var(--spacing-xl);
    }
    
    .header-title {
        font-size: var(--font-size-xxl);
    }
    
    .drill-navigation {
        justify-content: flex-start;
    }
    
    .chart-wrapper {
        padding: var(--spacing-xl);
    }
    
    /* Hover effects for desktop */
    .chart-wrapper:hover {
        box-shadow: var(--shadow-md);
        transition: box-shadow var(--transition-normal);
    }
}

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

/* Focus styles */
*:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* Touch feedback */
.nav-button:active,
.error-retry-btn:active {
    transform: scale(0.98);
}

.chart-wrapper {
    -webkit-tap-highlight-color: transparent;
}

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