:root {
    --bg: #f3f4f6;
    --surface: #ffffff;
    --surface-soft: #f9fafb;
    --border: #e5e7eb;
    --border-strong: #d1d5db;
    --text: #111827;
    --text-soft: #6b7280;
    --accent: #2563eb;
    --accent-soft: #eff6ff;
    --success: #16a34a;
    --radius-lg: 18px;
    --radius-md: 12px;
    --shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.06);
    --shadow-md: 0 8px 24px rgba(16, 24, 40, 0.08);
}

body.comfortable-ui {
    --space-page: 24px;
    --space-header-y: 28px;
    --space-header-x: 32px;
    --space-section: 20px;
    --space-gap-main: 20px;
    --space-gap-preview: 16px;
    --space-control-y: 10px;
    --space-control-x: 12px;
    --space-setting-group: 14px;
    --font-header-sub: 1rem;
    --font-setting-label: 0.92rem;
    --font-control: 0.95rem;
    --font-button: 0.9rem;
}

body.compact-ui {
    --space-page: 16px;
    --space-header-y: 20px;
    --space-header-x: 24px;
    --space-section: 14px;
    --space-gap-main: 14px;
    --space-gap-preview: 10px;
    --space-control-y: 8px;
    --space-control-x: 10px;
    --space-setting-group: 10px;
    --font-header-sub: 0.92rem;
    --font-setting-label: 0.86rem;
    --font-control: 0.9rem;
    --font-button: 0.84rem;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: Inter, 'Segoe UI', Roboto, -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg);
    min-height: 100vh;
    padding: var(--space-page, 24px);
    color: var(--text);
    line-height: 1.45;
}

/* iOS-safe page scroll lock: position:fixed on body is the only way to
   reliably prevent compositor-level scrolling on iOS WebKit.  The saved
   scroll offset is applied as negative top so the visual position stays. */
html.edit-mode-scroll-lock {
    overflow: hidden !important;
}

html.edit-mode-scroll-lock body {
    overflow: hidden !important;
    position: fixed !important;
    width: 100% !important;
    left: 0 !important;
}

/* Float the edit toolbar at the bottom of the screen while page scroll
   is locked so the buttons are always reachable on mobile. */
html.edit-mode-scroll-lock .upload-actions__edit-btns {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 9999;
    background: var(--surface);
    border-top: 1px solid var(--border);
    padding: 12px 16px;
    padding-bottom: calc(12px + env(safe-area-inset-bottom, 0px));
    align-items: center;
    box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.12);
}

.container {
    max-width: 1500px;
    margin: 0 auto;
    background: transparent;
}

header {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-header-y, 28px) var(--space-header-x, 32px);
    margin-bottom: var(--space-gap-main, 20px);
    box-shadow: var(--shadow-sm);
}

header h1 {
    font-size: clamp(1.8rem, 2.6vw, 2.3rem);
    font-weight: 700;
    color: var(--text);
    margin-bottom: 6px;
}

header p {
    color: var(--text-soft);
    font-size: var(--font-header-sub, 1rem);
}

.main-content {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 330px;
    gap: var(--space-gap-main, 20px);
    align-items: start;
    max-width: 100%;
    overflow: hidden;
}

.upload-section {
    grid-column: 1;
    grid-row: 1;
}

.side-panel {
    grid-column: 2;
    grid-row: 1 / span 2;
    display: flex;
    flex-direction: column;
    gap: var(--space-gap-main, 20px);
    position: sticky;
    top: 10px;
    align-self: start;
    max-height: calc(100vh - 20px);
    overflow-y: auto;
}

.upload-actions {
    width: 100%;
    justify-content: center;
    align-items: center;
    margin-top: 12px;
    gap: 10px;
}

.upload-image-name {
    font-size: 0.88rem;
    color: var(--text-soft);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    min-width: 0;
    text-align: center;
    width: 100%;
}

.upload-actions__btns {
    display: flex;
    flex-direction: column;
    gap: 6px;
    flex-shrink: 0;
    align-items: center;
    width: 100%;
}

/* Each row of action buttons is a horizontal flex row */
.upload-actions__row {
    display: flex;
    gap: 8px;
    justify-content: center;
}
.upload-area {
    border: 2px dashed var(--border-strong);
    border-radius: var(--radius-lg);
    padding: var(--space-section, 20px);
    text-align: center;
    transition: border-color 0.2s ease, background 0.2s ease, transform 0.2s ease;
    background: var(--surface);
    min-height: 0;
    max-height: none;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.upload-area.has-preview {
    justify-content: flex-start;
    align-items: stretch;
}

.upload-area:hover {
    border-color: var(--accent);
    background: var(--surface-soft);
}

.upload-area.drag-over {
    background: var(--accent-soft);
    border-color: var(--accent);
    transform: translateY(-1px);
}

.upload-area.rate-limit-locked:not(.has-preview) {
    background: #fff;
    border-color: #fff;
    cursor: not-allowed;
}

.visual-preview {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
    height: auto;
    max-height: 100%;
    min-height: 0;
    flex: 1 1 auto;
    cursor: pointer;
    overflow: hidden;
}

.upload-area.has-preview .visual-preview {
    min-height: 0;
}

.preview-images {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-gap-preview, 16px);
    width: 100%;
    height: 100%;
    max-height: 100%;
    min-height: 0;
    align-items: stretch;
}

.preview-images.layout-side-by-side {
    grid-template-columns: 1fr 1fr;
}

.preview-images.layout-stacked {
    grid-template-columns: 1fr;
    grid-template-rows: minmax(0, 1fr) minmax(0, 1fr);
}

.preview-column {
    background: var(--surface-soft);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 10px;
    min-height: 320px;
    display: flex;
    justify-content: center;
    align-items: center;
    min-width: 0;
    overflow: hidden;
}

.upload-area.has-preview .preview-column {
    min-height: 0;
}

.preview-images.layout-stacked .preview-column {
    min-height: 0;
    height: 100%;
}

.preview-media-viewport {
    position: relative;
    width: 100%;
    height: 100%;
    min-width: 0;
    min-height: 0;
    overflow: hidden;
    margin: auto;
    flex: 0 0 auto;
}

.preview-column img,
.preview-column canvas,
.visual-preview canvas {
    max-width: 100%;
    max-height: 100%;
    width: 100%;
    height: 100%;
    border-radius: 10px;
    border: 1px solid var(--border);
    background: #fff;
    object-fit: contain;
}

#originalImage {
    position: absolute;
    left: 50%;
    top: 50%;
    width: 100%;
    height: 100%;
    max-width: none;
    max-height: none;
    transform: translate(-50%, -50%);
}

#visualCanvas {
    position: absolute;
    left: 50%;
    top: 50%;
    width: auto;
    height: auto;
    max-width: none;
    max-height: none;
    object-fit: fill;
    transform: translate(-50%, -50%);
    transform-origin: center center;
    user-select: none;
    -webkit-user-drag: none;
}

/* Brush-cursor overlay must be fully transparent so the visual canvas beneath
   is visible — the generic `.visual-preview canvas { background: #fff }` rule
   would otherwise turn it into an opaque white layer. */
#brushCursorOverlay {
    background: transparent !important;
    border: none !important;
}

#originalImage,
#visualCanvas {
    cursor: pointer;
}

#visualCanvas.edit-mode {
    cursor: crosshair;
    outline: 2px solid var(--accent);
    outline-offset: 2px;
    border-radius: 10px;
    touch-action: none;
    -webkit-touch-callout: none;
}

/* Hide default cursor in contour edit mode — custom brush circle is drawn instead */
#visualCanvas.edit-mode.contour-brush-cursor {
    cursor: none;
}

#visualCanvas.edit-mode.is-panning {
    cursor: grabbing;
}

/* Eyedropper cursor while the colour-picker popup is open */
#visualCanvas.edit-mode.edit-eyedropper {
    cursor: copy;
}

.edit-touch-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 4;
    border-radius: 10px;
    background: transparent;
    pointer-events: none;
    touch-action: none;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
}

.edit-touch-overlay.is-active {
    pointer-events: auto;
}

/* ── Edit mode: floating colour-picker popup ────────────────────────────────
   Triggered by right-click (desktop) or double two-finger tap (mobile).
   Positioned near the trigger point, clamped inside the viewport.          */
.edit-color-picker {
    position: fixed;
    z-index: 10000;
    background: var(--surface);
    border: 1px solid var(--border-strong);
    border-radius: var(--radius-md);
    box-shadow: 0 6px 28px rgba(16, 24, 40, 0.24);
    padding: 8px;
    display: grid;
    grid-template-columns: repeat(6, 38px);
    gap: 5px;
    touch-action: auto;
    -webkit-user-select: none;
    user-select: none;
}

.edit-color-picker__swatch {
    position: relative;
    width: 38px;
    height: 38px;
    border-radius: 6px;
    border: 2px solid transparent;
    cursor: pointer;
    padding: 0;
    outline: none;
    transition: transform 0.1s ease, border-color 0.12s ease, box-shadow 0.12s ease;
    -webkit-tap-highlight-color: transparent;
    overflow: hidden;
}

.edit-color-picker__swatch:hover,
.edit-color-picker__swatch:focus-visible {
    transform: scale(1.15);
    border-color: var(--border-strong);
}

.edit-color-picker__swatch.is-selected {
    border-color: var(--accent);
    box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.35);
}

.edit-color-picker__code {
    position: absolute;
    bottom: 1px;
    right: 3px;
    font-size: 0.6rem;
    font-weight: 700;
    line-height: 1;
    pointer-events: none;
}

.hover-inspector-tooltip {
    position: fixed;
    z-index: 10001;
    min-width: 280px;
    max-width: min(360px, calc(100vw - 24px));
    background: rgba(17, 24, 39, 0.96);
    color: #f9fafb;
    border: 1px solid rgba(148, 163, 184, 0.35);
    border-radius: 12px;
    box-shadow: 0 10px 32px rgba(15, 23, 42, 0.34);
    padding: 10px 12px;
    pointer-events: none;
    backdrop-filter: blur(8px);
}

.hover-inspector-tooltip__title {
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.02em;
    margin-bottom: 8px;
    color: #e5e7eb;
}

.hover-inspector-tooltip__grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
}

.hover-inspector-tooltip__card {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 10px;
    padding: 9px;
}

.hover-inspector-tooltip__label {
    font-size: 0.72rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #cbd5e1;
    margin-bottom: 7px;
}

.hover-inspector-tooltip__swatch {
    display: block;
    width: 100%;
    height: 24px;
    border-radius: 7px;
    border: 1px solid rgba(255, 255, 255, 0.22);
    margin-bottom: 7px;
}

.hover-inspector-tooltip__code {
    font-size: 0.75rem;
    line-height: 1.35;
    color: #f8fafc;
    word-break: break-word;
}

#visualCanvas.hover-inspector-active,
.visual-canvas-viewport.hover-inspector-active #visualCanvas {
    cursor: crosshair;
}

.visual-canvas-viewport.edit-mode-touch-lock {
    touch-action: none;
    overscroll-behavior: contain;
    -webkit-user-select: none;
    user-select: none;
}

.upload-actions__edit-btns {
    display: flex;
    flex-direction: column;
    gap: 6px;
    width: 100%;
    align-items: center;
}

/* In edit mode each row is horizontally spaced */
.upload-actions__edit-btns .upload-actions__row {
    display: flex;
    gap: 10px;
    justify-content: center;
}

.edit-apply-mode-toggle {
    margin-right: auto;
    background: transparent;
    border: 0;
    padding: 0;
    cursor: pointer;
    touch-action: manipulation;
    -webkit-tap-highlight-color: transparent;
    user-select: none;
}

.edit-apply-mode-toggle__track {
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: space-between;
    min-width: 146px;
    height: 40px;
    padding: 4px;
    border-radius: 999px;
    border: 1px solid var(--border-strong);
    background: linear-gradient(135deg, #eef2ff 0%, #f8fafc 100%);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.85);
}

.edit-apply-mode-toggle__option {
    position: relative;
    z-index: 1;
    flex: 1 1 50%;
    text-align: center;
    font-size: 0.82rem;
    font-weight: 700;
    color: var(--text-soft);
    transition: color 0.18s ease;
    white-space: nowrap;
}

.edit-apply-mode-toggle__thumb {
    position: absolute;
    top: 4px;
    left: 4px;
    width: calc(50% - 4px);
    height: calc(100% - 8px);
    border-radius: 999px;
    background: var(--accent);
    box-shadow: 0 2px 10px rgba(37, 99, 235, 0.3);
    transition: transform 0.2s ease;
}

.edit-apply-mode-toggle.is-zone .edit-apply-mode-toggle__thumb {
    transform: translateX(100%);
}

.edit-apply-mode-toggle:not(.is-zone) .edit-apply-mode-toggle__option--left,
.edit-apply-mode-toggle.is-zone .edit-apply-mode-toggle__option--right {
    color: #fff;
}

.edit-apply-mode-toggle:focus-visible .edit-apply-mode-toggle__track {
    outline: 3px solid rgba(37, 99, 235, 0.24);
    outline-offset: 2px;
}

.edit-apply-mode-toggle:hover .edit-apply-mode-toggle__track {
    border-color: var(--accent);
}

.edit-accept-btn {
    background: var(--success);
    color: #fff;
    border-color: var(--success);
}

.edit-accept-btn:hover {
    filter: brightness(0.96);
}

.preview-images.layout-stacked .preview-column img,
.preview-images.layout-stacked .preview-column canvas,
.preview-images.layout-stacked .visual-preview canvas {
    max-height: 100%;
}

.upload-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.upload-content svg {
    color: var(--accent);
    margin-bottom: 16px;
}

.upload-content p {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 8px;
}

.upload-content span {
    color: var(--text-soft);
    font-size: 0.9rem;
}

.settings-section {
    background: var(--surface);
    border: 2px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-section, 20px);
    box-shadow: var(--shadow-sm);
}

/* ── Footer + legal pages ─────────────────────────────────────────────────── */

.site-footer {
    margin-top: var(--space-gap-main, 20px);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 14px 18px;
    box-shadow: var(--shadow-sm);
    color: var(--text-soft);
    font-size: 0.92rem;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
    text-align: center;
}

.site-footer__right {
    display: inline-flex;
    gap: 10px;
    align-items: center;
}

.site-footer a {
    color: var(--accent);
    text-decoration: none;
}

.site-footer a:hover {
    text-decoration: underline;
}

.site-footer__sep {
    color: var(--text-soft);
}

.legal-main {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-section, 20px);
    box-shadow: var(--shadow-sm);
}

.legal-main h2 {
    font-size: 1.2rem;
    margin: 16px 0 8px;
}

.legal-main p,
.legal-main li {
    color: var(--text);
}

.legal-main ul {
    padding-left: 18px;
    margin: 8px 0 14px;
}

.legal-toplink {
    display: inline-block;
    margin-bottom: 12px;
    color: var(--accent);
    text-decoration: none;
}

.legal-toplink:hover {
    text-decoration: underline;
}

.cookie-banner {
    position: fixed;
    left: 16px;
    right: 16px;
    bottom: 16px;
    z-index: 9999;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: 14px 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.cookie-banner__text {
    color: var(--text);
    display: inline-flex;
    gap: 8px;
    align-items: baseline;
    flex-wrap: wrap;
}

.cookie-banner__text a {
    color: var(--accent);
    text-decoration: none;
}

.cookie-banner__text a:hover {
    text-decoration: underline;
}

.cookie-banner__actions {
    display: inline-flex;
    gap: 10px;
    align-items: center;
}

.cookie-banner__btn {
    border: 1px solid var(--border-strong);
    background: var(--surface-soft);
    color: var(--text);
    border-radius: 999px;
    padding: 8px 12px;
    font-size: 0.9rem;
    cursor: pointer;
}

.cookie-banner__btn:hover {
    background: var(--accent-soft);
    border-color: var(--accent);
}

.cookie-banner__btn--primary {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
}

.cookie-banner__btn--primary:hover {
    background: var(--accent);
}

.legend-section {
    background: var(--surface);
    border: 2px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-section, 20px);
    box-shadow: var(--shadow-sm);
}

.legend-section h2 {
    color: var(--text);
    margin-bottom: 14px;
    font-size: 1.08rem;
    font-weight: 700;
    display: none;
}

.legend-content {
    display: grid;
    grid-template-columns: 1fr;
    gap: 10px;
    min-height: 120px;
    max-height: 460px;
    overflow: auto;
    padding-right: 6px;
}

.legend-item {
    display: grid;
    grid-template-columns: 40px 1fr;
    gap: 10px;
    align-items: center;
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 8px;
    background: var(--surface-soft);
}

.legend-swatch {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    border: 1px solid var(--border-strong);
    display: flex;
    align-items: center;
    justify-content: center;
}

.legend-code {
    font-size: 0.86rem;
    font-weight: 700;
}

.legend-name {
    font-size: 0.86rem;
    color: var(--text);
    font-weight: 600;
}

.legend-item.edit-selectable {
    cursor: pointer;
    transition: box-shadow 0.15s ease, transform 0.1s ease, outline-color 0.15s ease;
}

.legend-item.edit-selectable:hover {
    transform: translateX(2px);
}

.legend-item.is-selected {
    outline: 2px solid var(--accent);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.28);
}

/* ── Paint set inline row (select + cluster count) ───────────────────── */

.paint-set-row {
    display: flex;
    gap: 6px;
    align-items: center;
}

.paint-set-row select {
    flex: 1 1 auto;
    min-width: 0;
}

.paint-set-cluster-input {
    width: 64px !important;
    flex: 0 0 64px;
    text-align: center;
}

/* ── Paint Set legend toggle button active state ─────────────────────── */

.download-btn.paint-set-active {
    border-color: var(--accent);
    background: var(--accent-soft);
}

/* ── Painting technique: recipe display ───────────────────────────────── */

.legend-item--painting {
    grid-template-columns: 40px 1fr;
}

.legend-info {
    display: flex;
    flex-direction: column;
    gap: 2px;
    min-width: 0;
}

.legend-recipe-workflow {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    min-width: 0;
}

.legend-recipe-orders {
    font-size: 0.68rem;
    font-weight: 600;
    color: var(--text-muted, #64748b);
    letter-spacing: 0.02em;
    white-space: nowrap;
}

.legend-recipe {
    font-size: 0.76rem;
    color: var(--text-muted, #6b7280);
    font-weight: 400;
    line-height: 1.3;
    word-break: break-word;
}

.legend-recipe-quality {
    display: inline-block;
    flex: 0 0 auto;
    font-size: 0.66rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.03em;
    padding: 1px 5px;
    border-radius: 4px;
    vertical-align: middle;
}

.legend-recipe-quality--excellent {
    background: #d1fae5;
    color: #065f46;
}

.legend-recipe-quality--good {
    background: #dbeafe;
    color: #1e40af;
}

.legend-recipe-quality--acceptable {
    background: #fef3c7;
    color: #92400e;
}

.legend-recipe-quality--poor {
    background: #fee2e2;
    color: #991b1b;
}

.legend-recipe-progress {
    font-size: 0.82rem;
    color: var(--text-muted, #6b7280);
    text-align: center;
    padding: 8px;
    font-style: italic;
}

.settings-section h2 {
    color: var(--text);
    margin-bottom: 16px;
    font-size: 1.2rem;
    font-weight: 700;
    display: none;
}

.setting-group {
    margin-bottom: var(--space-setting-group, 14px);
}

.setting-group label {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: 7px;
    color: #374151;
    font-size: var(--font-setting-label, 0.92rem);
    font-weight: 600;
}

.setting-group label #gridPixelsValue {
    color: var(--accent);
    font-weight: 700;
}

.setting-group input[type='number'],
.setting-group select {
    width: 100%;
    padding: var(--space-control-y, 10px) var(--space-control-x, 12px);
    border: 1px solid var(--border-strong);
    border-radius: 10px;
    font-size: var(--font-control, 0.95rem);
    color: var(--text);
    background: #fff;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.setting-group input[type='number']:focus,
.setting-group select:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

.setting-group input[type='range'] {
    width: 100%;
    height: 7px;
    background: #e5e7eb;
    border-radius: 999px;
    outline: none;
    -webkit-appearance: none;
    appearance: none;
}

.setting-group input[type='range']::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    background: var(--accent);
    border: 2px solid #fff;
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 0 0 1px rgba(37, 99, 235, 0.35);
}

.setting-group input[type='range']::-moz-range-thumb {
    width: 18px;
    height: 18px;
    background: var(--accent);
    border: 2px solid #fff;
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 0 0 1px rgba(37, 99, 235, 0.35);
}

.results-section {
    display: none !important;
    grid-column: 1;
    grid-row: 2;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-section, 18px);
    box-shadow: var(--shadow-sm);
}

.results-section canvas,
.tab-content canvas {
    max-width: 100%;
    border: 1px solid var(--border-strong);
    border-radius: 10px;
    background: #fff;
    display: block;
    margin: 0 auto 14px;
}

.button-group {
    display: flex;
    gap: 10px;
    justify-content: flex-end;
    margin-top: 4px;
}

.legend-buttons {
    margin-top: 12px;
    justify-content: center;
}

.download-btn {
    margin: 0;
    padding: calc(var(--space-control-y, 10px) - 1px) calc(var(--space-control-x, 12px) + 4px);
    background: #fff;
    color: var(--text);
    border: 1px solid var(--border-strong);
    border-radius: 10px;
    font-size: var(--font-button, 0.9rem);
    font-weight: 600;
    cursor: pointer;
    transition: border-color 0.2s ease, background 0.2s ease, transform 0.2s ease;
}

.download-btn:hover {
    border-color: var(--accent);
    background: var(--accent-soft);
    transform: translateY(-1px);
}

.download-btn:active {
    transform: translateY(0);
}

.download-btn:disabled {
    opacity: 0.45;
    cursor: not-allowed;
    transform: none;
}

.preview-toggle {
    margin: 0;
    padding: 0;
    border: none;
    background: transparent;
    cursor: pointer;
}

.preview-toggle__track {
    position: relative;
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: center;
    min-width: 150px;
    padding: 3px;
    border: 1px solid var(--border-strong);
    border-radius: 999px;
    background: #fff;
    box-shadow: var(--shadow-sm);
    overflow: hidden;
}

.preview-toggle__option {
    position: relative;
    z-index: 1;
    padding: 7px 14px;
    text-align: center;
    font-size: var(--font-button, 0.9rem);
    font-weight: 600;
    color: var(--text-soft);
    transition: color 0.2s ease;
    user-select: none;
}

.preview-toggle__thumb {
    position: absolute;
    top: 3px;
    bottom: 3px;
    left: 3px;
    width: calc(50% - 3px);
    border-radius: 999px;
    background: var(--accent-soft);
    border: 1px solid rgba(37, 99, 235, 0.18);
    transition: transform 0.22s ease;
}

.preview-toggle:hover .preview-toggle__track {
    border-color: var(--accent);
}

.preview-toggle:hover .preview-toggle__thumb {
    background: #dbeafe;
}

.preview-toggle.is-original .preview-toggle__thumb {
    transform: translateX(0);
}

.preview-toggle:not(.is-original) .preview-toggle__thumb {
    transform: translateX(100%);
}

.preview-toggle.is-original .preview-toggle__option--left,
.preview-toggle:not(.is-original) .preview-toggle__option--right {
    color: var(--text);
}

.preview-toggle:focus-visible .preview-toggle__track {
    outline: 2px solid rgba(37, 99, 235, 0.35);
    outline-offset: 2px;
}

.preview-toggle:disabled {
    opacity: 0.45;
    cursor: not-allowed;
}

.preview-toggle:disabled .preview-toggle__track {
    border-color: var(--border-strong);
}

.apply-group {
    margin-top: 8px;
}

.advanced-settings-toggle {
    margin-top: 10px;
}

.advanced-settings-btn {
    width: 100%;
}

.advanced-settings-panel {
    margin-top: 14px;
    padding: 14px;
    border: 1px solid var(--border);
    border-radius: 12px;
    background: var(--surface-soft);
}

.advanced-settings-panel h3 {
    margin-bottom: 12px;
    color: var(--text);
    font-size: 1rem;
    font-weight: 700;
}

.advanced-settings-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
}

.advanced-settings-grid--quantization .setting-group {
    margin-bottom: 0;
}

.advanced-settings-subsection {
    margin-top: 14px;
    padding-top: 14px;
    border-top: 1px solid var(--border);
}

.advanced-settings-subsection:first-of-type {
    margin-top: 0;
    padding-top: 0;
    border-top: none;
}

.advanced-settings-help {
    margin: 6px 0 12px;
    color: var(--text-soft);
    font-size: 0.82rem;
    line-height: 1.4;
}

.advanced-settings-subsection .setting-group:last-child {
    margin-bottom: 0;
}

.advanced-settings-divider {
    margin: 16px 0 14px;
    border: 0;
    border-top: 1px solid var(--border);
}

.advanced-settings-check {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.advanced-settings-check input[type='checkbox'] {
    width: 18px;
    height: 18px;
    accent-color: var(--accent);
    flex: 0 0 auto;
}

.advanced-settings-actions {
    margin-top: 4px;
}

.advanced-settings-reset-btn {
    width: 100%;
}

.advanced-settings-panel .setting-group:last-child {
    margin-bottom: 0;
}

.apply-btn {
    width: 100%;
    padding: calc(var(--space-control-y, 10px)) calc(var(--space-control-x, 12px));
    background: var(--accent-soft);
    color: var(--text);
    border: 1px solid var(--border-strong);
    border-radius: 10px;
    font-size: var(--font-button, 0.9rem);
    font-weight: 600;
    cursor: pointer;
    transition: border-color 0.2s ease, background 0.2s ease, transform 0.2s ease, opacity 0.2s ease;
}

.apply-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none;
}

.apply-btn.rate-limit-locked {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none;
}

.apply-btn.has-changes {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
    animation: pulse-apply 1.4s ease-in-out infinite;
}


.apply-btn:not(:disabled):hover {
    border-color: var(--accent);
    transform: translateY(-1px);
}

.apply-btn:not(:disabled):active {
    transform: translateY(0);
}

.human-check-modal[hidden] {
    display: none;
}

.human-check-modal {
    position: fixed;
    inset: 0;
    z-index: 1200;
    display: grid;
    place-items: center;
    padding: 16px;
}

.human-check-modal__backdrop {
    position: absolute;
    inset: 0;
    background: rgba(17, 24, 39, 0.55);
    backdrop-filter: blur(3px);
}

.human-check-modal__dialog {
    position: relative;
    width: min(100%, 420px);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 22px;
    box-shadow: var(--shadow-md);
}

.human-check-modal__dialog h2 {
    font-size: 1.25rem;
    margin-bottom: 10px;
}

.human-check-modal__dialog p {
    color: var(--text-soft);
}

.human-check-modal__widget {
    margin: 18px 0 12px;
    min-height: 70px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.human-check-modal__status {
    min-height: 1.4em;
    font-size: 0.92rem;
}

.human-check-modal__actions {
    display: flex;
    justify-content: flex-end;
    margin-top: 14px;
}

@keyframes pulse-apply {
    0%, 100% { opacity: 1; }
    50%       { opacity: 0.75; }
}

@media (max-width: 1100px) {
    .main-content {
        grid-template-columns: 1fr;
    }

    .upload-section,
    .side-panel,
    .results-section {
        grid-column: 1;
        grid-row: auto;
    }

    .side-panel {
        position: static;
    }

    .button-group {
        justify-content: center;
    }

    /* Always stack the two previews vertically on mobile.
       Using flex-column is immune to any grid-template-columns rule or
       JS-applied layout class, so this is the single source of truth.  */
    .preview-images,
    .preview-images.layout-side-by-side,
    .preview-images.layout-stacked {
        display: flex !important;
        flex-direction: column !important;
        height: auto !important;
        gap: var(--space-gap-preview, 16px);
    }

    /* Each column must size to its content height – the image aspect ratio
       drives the height via inline aspect-ratio set by JS.              */
    .preview-column {
        width: 100% !important;
        height: auto !important;
        min-height: 0 !important;
        max-width: 100%;
        box-sizing: border-box;
        overflow: hidden;
    }

    /* Viewport: width:100% so it never overflows; height:auto so that the
       inline aspect-ratio property (set by JS) can compute the height.   */
    .preview-media-viewport {
        width: 100% !important;
        max-width: 100% !important;
        height: auto !important;
        box-sizing: border-box;
    }

    /* visual-preview must also be auto-height on mobile */
    .visual-preview {
        height: auto !important;
    }

    /* Contain the whole upload area to viewport width */
    .upload-section,
    .upload-area {
        max-width: 100%;
        box-sizing: border-box;
        overflow: hidden;
    }
}

@media (max-width: 768px) {
    body {
        padding: 14px;
    }

    header,
    .upload-area,
    .settings-section,
    .results-section {
        border-radius: 14px;
    }

    header {
        padding: 20px;
    }

    .preview-column {
        min-height: 260px;
    }
}