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

:root {
    color-scheme: dark;
    --bg: #1a1a1a;
    --panel: #2a2a2a;
    --surface: #222;
    --field: #333;
    --border: #444;
    --border-soft: #363636;
    --text: #e0e0e0;
    --text-strong: #fff;
    --muted: #888;
    --muted-dark: #666;
    --accent: #4a9eff;
    --accent-hover: #3a8eef;
    --success: #6bff6b;
    --danger: #ff6b6b;
}

[hidden] {
    display: none !important;
}

body,
button,
input,
select,
textarea {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

body {
    min-height: 100vh;
    padding: 20px;
    background: var(--bg);
    color: var(--text);
}

button,
select,
textarea,
input {
    font: inherit;
}

.app-shell {
    width: min(1200px, 100%);
    margin: 0 auto;
    display: grid;
    gap: 20px;
}

.page-header {
    text-align: center;
    padding: 8px 0 2px;
}

h1 {
    color: var(--text-strong);
    font-size: clamp(1.8rem, 4vw, 2.35rem);
    line-height: 1.1;
    letter-spacing: -0.035em;
}

.page-header p {
    margin-top: 7px;
    color: var(--muted-dark);
    font-size: 12px;
}

.page-header code {
    color: var(--muted);
}

.api-key-bar,
.panel {
    background: var(--panel);
    border-radius: 12px;
}

.api-key-bar {
    padding: 12px 16px;
}

.api-key-status {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 0;
    border: 0;
    background: transparent;
    color: var(--muted);
    cursor: pointer;
    font-size: 13px;
    font-weight: 400;
    text-align: left;
}

.api-key-status:hover {
    background: transparent;
    color: #aaa;
}

.status-dot {
    width: 8px;
    height: 8px;
    flex: 0 0 auto;
    border-radius: 50%;
    background: var(--danger);
}

.status-dot.active {
    background: var(--success);
}

.api-key-input-wrapper {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-top: 12px;
    flex-wrap: wrap;
}

.api-key-input-wrapper input {
    min-width: 220px;
    flex: 1;
}

.api-link {
    color: var(--accent);
    font-size: 12px;
    text-decoration: none;
}

.api-link:hover {
    text-decoration: underline;
}

.primary-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
    align-items: stretch;
}

.panel {
    min-width: 0;
    padding: 20px;
}

.input-card,
.output-card,
.region-output-card,
.compare-view-card,
.region-diff-card,
.diff-card {
    display: flex;
    flex-direction: column;
}

.panel-heading {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 15px;
}

.panel-heading h2,
.panel-heading h3 {
    color: var(--muted);
    font-size: 0.88rem;
    font-weight: 650;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.compact-heading span {
    color: var(--muted-dark);
    font-size: 11px;
    text-align: right;
}

.image-area,
.output-area,
.compare-area {
    min-height: 310px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    border-radius: 8px;
    background: var(--surface);
}

.image-area {
    border: 2px dashed var(--border);
    cursor: pointer;
    transition: border-color 0.2s;
}

.image-area:hover,
.image-area.dragover {
    border-color: var(--accent);
}

.image-area img,
.output-area img,
.compare-area img,
.compare-area canvas {
    display: block;
    max-width: 100%;
    max-height: 420px;
    object-fit: contain;
}

.compare-area canvas {
    cursor: crosshair;
}

.placeholder {
    padding: 20px;
    color: #5c5c5c;
    font-size: 14px;
    line-height: 1.45;
    text-align: center;
}

textarea,
select,
.api-key-input-wrapper input {
    border: 1px solid var(--border);
    border-radius: 7px;
    background: var(--field);
    color: var(--text);
}

textarea {
    width: 100%;
    min-height: 96px;
    margin-top: 15px;
    padding: 12px;
    resize: vertical;
    font-size: 14px;
    line-height: 1.45;
}

select,
.api-key-input-wrapper input {
    min-height: 36px;
    padding: 8px 10px;
    font-size: 13px;
}

textarea:focus,
select:focus,
input:focus-visible,
button:focus-visible,
a:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

.editor-controls {
    display: grid;
    grid-template-columns: minmax(0, 0.8fr) minmax(0, 1fr) minmax(140px, 1fr);
    gap: 12px;
    margin-top: 15px;
    align-items: end;
}

.setting-group,
.compare-picker {
    min-width: 0;
}

.setting-group label,
.tool-control label,
.compare-picker > span {
    display: block;
    margin-bottom: 5px;
    color: var(--muted);
    font-size: 11px;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}

.setting-group select,
.compare-picker select {
    width: 100%;
}

button {
    min-height: 36px;
    padding: 9px 15px;
    border: 0;
    border-radius: 8px;
    background: var(--accent);
    color: #fff;
    cursor: pointer;
    font-size: 13px;
    font-weight: 650;
    transition: background 0.18s, opacity 0.18s;
}

button:hover {
    background: var(--accent-hover);
}

button:disabled {
    background: #505050;
    color: #8a8a8a;
    cursor: not-allowed;
}

button.secondary {
    background: #444;
    color: var(--text);
}

button.secondary:hover {
    background: #505050;
}

.primary-action {
    width: 100%;
}

.overlay-actions {
    position: absolute;
    z-index: 2;
    top: 10px;
    right: 10px;
    display: flex;
    gap: 6px;
}

.overlay-btn {
    min-height: 30px;
    padding: 7px 10px;
    background: rgba(74, 158, 255, 0.92);
    font-size: 11px;
}

.image-area > .overlay-btn {
    position: absolute;
    z-index: 2;
    top: 10px;
    right: 10px;
}

.overlay-btn.danger {
    background: rgba(255, 107, 107, 0.92);
}

.status,
.text-response {
    margin-top: 15px;
    padding: 10px 12px;
    border-radius: 8px;
    font-size: 13px;
    line-height: 1.45;
}

.status.error {
    background: #3a1a1a;
    color: var(--danger);
}

.status.success {
    background: #1a3a1a;
    color: var(--success);
}

.status.loading {
    background: #1a2a3a;
    color: #6bb3ff;
}

.text-response {
    background: var(--surface);
    white-space: pre-wrap;
}

.region-workspace {
    display: grid;
    gap: 14px;
    padding-top: 4px;
}

.section-heading {
    display: flex;
    align-items: end;
    justify-content: space-between;
    gap: 20px;
    padding: 2px 2px 0;
}

.section-heading h2 {
    color: var(--text-strong);
    font-size: 1.25rem;
    letter-spacing: -0.02em;
}

.section-heading > p {
    max-width: 560px;
    color: var(--muted);
    font-size: 12px;
    line-height: 1.45;
    text-align: right;
}

.eyebrow {
    margin-bottom: 3px;
    color: var(--accent);
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}

.region-grid {
    display: grid;
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 20px;
    align-items: stretch;
}

.diff-card {
    grid-column: span 8;
}

.tools-card {
    grid-column: span 4;
}

.region-output-card,
.compare-view-card,
.region-diff-card {
    grid-column: span 4;
}

.region-grid .compare-area,
.region-grid .output-area {
    min-height: 260px;
    flex: 1;
}

.selection-status {
    margin-top: 10px;
    color: var(--muted);
    font-size: 12px;
    line-height: 1.45;
}

.mask-legend {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 8px;
    color: var(--muted-dark);
    font-size: 10px;
}

.mask-legend span {
    display: inline-flex;
    align-items: center;
    gap: 5px;
}

.mask-legend i {
    width: 8px;
    height: 8px;
    border: 2px solid;
    border-radius: 50%;
}

.mask-legend .draft-swatch {
    border-color: #4a9eff;
}

.mask-legend .applied-swatch {
    border-color: #6bff6b;
}

.mask-legend .inverse-swatch {
    border-color: #ffb347;
}

.tool-stack {
    display: grid;
    gap: 10px;
}

.tool-control,
.toggle-row {
    padding: 11px 12px;
    border: 1px solid var(--border-soft);
    border-radius: 8px;
    background: var(--surface);
}

.split-control {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    align-items: center;
    gap: 12px;
}

.split-control label {
    margin-bottom: 0;
}

.tool-control-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 8px;
}

.tool-control-header label {
    margin-bottom: 0;
}

.tool-control output {
    color: var(--text);
    font-size: 12px;
    font-weight: 650;
}

.tool-control input[type="range"] {
    width: 100%;
    accent-color: var(--accent);
}

.control-note {
    display: block;
    margin-top: 5px;
    color: var(--muted-dark);
    font-size: 10px;
}

.toggle-row {
    display: flex;
    align-items: center;
    gap: 9px;
    color: var(--text);
    cursor: pointer;
    font-size: 12px;
}

.toggle-row input {
    width: 16px;
    height: 16px;
    accent-color: var(--accent);
}

.button-row {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px;
}

.compare-source-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px;
    margin-bottom: 10px;
}

.compare-picker {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    align-items: center;
    gap: 8px;
}

.compare-picker > span {
    margin-bottom: 0;
}

.compare-picker select:disabled {
    color: var(--muted-dark);
}

.compare-label,
.compare-hint {
    position: absolute;
    z-index: 2;
    padding: 5px 9px;
    border-radius: 5px;
    background: rgba(0, 0, 0, 0.72);
    font-size: 11px;
}

.compare-label {
    top: 10px;
    left: 10px;
    color: #fff;
}

.compare-hint {
    bottom: 10px;
    left: 50%;
    color: #aaa;
    transform: translateX(-50%);
    white-space: nowrap;
}

@media (max-width: 960px) {
    .primary-grid {
        grid-template-columns: 1fr;
    }

    .diff-card,
    .tools-card {
        grid-column: span 12;
    }

    .region-output-card,
    .compare-view-card,
    .region-diff-card {
        grid-column: span 6;
    }

    .region-diff-card {
        grid-column-start: 4;
    }
}

@media (max-width: 720px) {
    body {
        padding: 12px;
    }

    .app-shell,
    .primary-grid,
    .region-grid {
        gap: 12px;
    }

    .panel {
        padding: 15px;
    }

    .api-key-input-wrapper {
        align-items: stretch;
    }

    .api-key-input-wrapper input {
        min-width: 100%;
    }

    .section-heading {
        display: block;
    }

    .section-heading > p {
        margin-top: 5px;
        text-align: left;
    }

    .region-output-card,
    .compare-view-card,
    .region-diff-card {
        grid-column: span 12;
    }

    .image-area,
    .output-area,
    .compare-area,
    .region-grid .compare-area,
    .region-grid .output-area {
        min-height: 240px;
    }
}

@media (max-width: 520px) {
    .editor-controls {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .primary-action {
        grid-column: span 2;
    }

    .compact-heading {
        display: block;
    }

    .compact-heading span {
        display: block;
        margin-top: 3px;
        text-align: left;
    }
}