/* =========================================================
   MOBILE STYLES — Tab navigation, responsive layout, touch
   Breakpoints: 900px (tablet), 480px (phone), landscape
   ========================================================= */

/* === Mobile Tab Navigation (hidden on desktop) === */
.mobile-tabs {
    display: none;
}

/* =========================================================
   TABLET & PHONE — max-width: 900px
   ========================================================= */
@media (max-width: 900px) {
    /* --- Header compact --- */
    header {
        padding: 1rem 1rem 0.75rem;
        padding-top: calc(1rem + var(--safe-top));
    }

    header h1 {
        font-size: 1.5rem;
    }

    .subtitle {
        font-size: 0.8rem;
    }

    /* --- Mobile tab bar --- */
    .mobile-tabs {
        display: flex;
        position: sticky;
        top: 0;
        z-index: 50;
        background: var(--bg-secondary);
        border-bottom: 1px solid var(--border);
        padding: 0;
    }

    .mobile-tab {
        flex: 1;
        padding: 0.75rem 0.5rem;
        text-align: center;
        font-size: 0.85rem;
        font-weight: 600;
        color: var(--text-secondary);
        background: none;
        border: none;
        border-bottom: 2px solid transparent;
        cursor: pointer;
        transition: all 0.2s;
        -webkit-tap-highlight-color: transparent;
    }

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

    .mobile-tab-icon {
        display: block;
        font-size: 1.2rem;
        margin-bottom: 0.15rem;
    }

    /* --- Layout single column --- */
    main {
        grid-template-columns: 1fr;
        padding: 0.75rem;
        gap: 0.75rem;
    }

    /* --- Tab visibility --- */
    .controls-panel {
        position: static;
        border-radius: 8px;
        padding: 1rem;
    }

    .controls-panel.mobile-hidden,
    .results-panel.mobile-hidden {
        display: none;
    }

    /* --- Collapsible sections --- */
    .collapsible-header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        cursor: pointer;
        padding: 0.6rem 0;
        -webkit-tap-highlight-color: transparent;
        user-select: none;
    }

    .collapsible-header h3 {
        font-size: 0.85rem;
        color: var(--accent);
        font-weight: 600;
        text-transform: uppercase;
        letter-spacing: 0.04em;
    }

    .collapsible-arrow {
        color: var(--text-secondary);
        font-size: 0.75rem;
        transition: transform 0.2s;
    }

    .collapsible-header.collapsed .collapsible-arrow {
        transform: rotate(-90deg);
    }

    .collapsible-content {
        overflow: hidden;
        transition: max-height 0.3s ease;
    }

    .collapsible-content.collapsed {
        max-height: 0 !important;
        overflow: hidden;
    }

    /* --- Touch-friendly inputs (min 44px tap targets) --- */
    .control-group select,
    .control-group input[type="number"],
    .control-group input[type="text"] {
        padding: 0.6rem 0.75rem;
        font-size: 16px; /* Prevents iOS auto-zoom on focus */
        border-radius: 8px;
        min-height: 44px;
    }

    /* --- Editable range number inputs --- */
    .range-num-input {
        font-size: 16px; /* Prevents iOS auto-zoom */
        min-height: 40px;
        width: 80px;
        padding: 0.4rem 0.3rem;
    }

    .control-group input[type="range"] {
        height: 36px;
        margin-top: 0.15rem;
    }

    .control-group input[type="range"]::-webkit-slider-thumb {
        width: 28px;
        height: 28px;
    }

    .control-group input[type="range"]::-moz-range-thumb {
        width: 28px;
        height: 28px;
    }

    .checkbox-label {
        min-height: 44px;
        padding: 0.25rem 0;
    }

    .checkbox-label input[type="checkbox"] {
        width: 22px;
        height: 22px;
    }

    /* --- Tooltip tap support --- */
    .tooltip {
        width: 22px;
        height: 22px;
        font-size: 0.65rem;
    }

    .tooltip.active::after {
        width: 200px;
    }

    .tooltip::after {
        left: auto;
        right: -8px;
        transform: none;
    }

    /* --- Compact sensor details --- */
    .sensor-details {
        padding: 0.6rem;
        border-radius: 6px;
    }

    /* --- Rule cards 3-column compact --- */
    .rule-cards {
        grid-template-columns: repeat(3, 1fr);
        gap: 0.5rem;
    }

    .rule-card {
        padding: 0.75rem 0.5rem;
    }

    .rule-card h3 {
        font-size: 0.75rem;
    }

    .rule-value {
        font-size: 1.2rem;
    }

    .rule-desc {
        font-size: 0.65rem;
    }

    .active-shutter {
        padding: 0.6rem 0.75rem;
        font-size: 0.85rem;
    }

    /* --- Exposure cards 2-column --- */
    .exposure-cards {
        grid-template-columns: repeat(2, 1fr);
        gap: 0.5rem;
    }

    .exposure-card {
        padding: 0.75rem 0.5rem;
    }

    .exposure-value {
        font-size: 1.1rem;
    }

    /* --- Section padding reduction --- */
    .rule-results, .exposure-info, .info-section {
        padding: 1rem;
        border-radius: 8px;
    }

    .preview-container {
        padding: 1rem;
        border-radius: 8px;
    }

    /* --- Stacked grids --- */
    .comparison-grid {
        grid-template-columns: 1fr;
        gap: 0.75rem;
    }

    .info-grid {
        grid-template-columns: 1fr;
        gap: 0.75rem;
    }

    .info-block .formula {
        font-size: 0.7rem;
        word-break: break-all;
    }

    /* --- Bigger action buttons --- */
    .action-buttons {
        gap: 0.5rem;
    }

    .btn {
        padding: 0.65rem 0.75rem;
        font-size: 0.85rem;
        min-height: 44px;
        border-radius: 8px;
    }

    /* --- Footer compact --- */
    footer {
        margin-top: 1rem;
        padding: 1rem;
        padding-bottom: calc(1rem + var(--safe-bottom));
    }
}

/* =========================================================
   SMALL PHONE — max-width: 480px
   ========================================================= */
@media (max-width: 480px) {
    main {
        padding: 0.5rem;
        gap: 0.5rem;
    }

    header h1 {
        font-size: 1.3rem;
    }

    /* Rule cards become horizontal list items */
    .rule-cards {
        grid-template-columns: 1fr;
        gap: 0.4rem;
    }

    .rule-card {
        display: flex;
        align-items: center;
        justify-content: space-between;
        text-align: left;
        padding: 0.65rem 0.75rem;
    }

    .rule-card h3 {
        font-size: 0.8rem;
        margin-bottom: 0;
        min-width: 70px;
    }

    .rule-value {
        font-size: 1.3rem;
        flex-shrink: 0;
    }

    .rule-desc {
        display: none;
    }

    .exposure-cards {
        grid-template-columns: repeat(2, 1fr);
    }

    .exposure-label {
        font-size: 0.65rem;
    }

    .exposure-value {
        font-size: 1rem;
    }

    .control-row {
        gap: 0.5rem;
    }
}

/* =========================================================
   LANDSCAPE MOBILE
   ========================================================= */
@media (max-width: 900px) and (orientation: landscape) {
    header {
        padding: 0.5rem 1rem;
        padding-top: calc(0.5rem + var(--safe-top));
    }

    header h1 {
        font-size: 1.2rem;
    }

    .subtitle {
        display: none;
    }

    .mobile-tabs {
        padding: 0;
    }

    .mobile-tab {
        padding: 0.4rem 0.5rem;
        font-size: 0.8rem;
    }

    .mobile-tab-icon {
        display: inline;
        margin-right: 0.3rem;
        margin-bottom: 0;
    }

    .preview-wrapper {
        max-height: 50vh;
        aspect-ratio: auto;
    }

    .preview-wrapper #sky-preview {
        max-height: 50vh;
    }
}

/* =========================================================
   TOUCH DEVICE ENHANCEMENTS
   Replaces hover states with active states for touch screens
   ========================================================= */
@media (hover: none) and (pointer: coarse) {
    .rule-card.clickable:hover {
        border-color: var(--border);
        background: var(--bg-card);
    }

    .rule-card.clickable:active {
        border-color: rgba(99, 102, 241, 0.5);
        background: rgba(26, 34, 52, 0.8);
    }

    .btn:hover {
        border-color: var(--border);
        background: var(--bg-card);
    }

    .btn:active {
        border-color: var(--accent);
        background: var(--bg-input);
        transform: scale(0.97);
    }

    .btn-primary:hover {
        background: var(--accent);
        border-color: var(--accent);
    }

    .btn-primary:active {
        background: #5558e6;
        border-color: #5558e6;
    }

    /* Remove tooltip hover — handled by JS tap */
    .tooltip:hover::after {
        content: none;
    }
}