:root {
    color-scheme: dark;
    --bg: #0b0e14;
    --panel: #12161f;
    --panel-border: #232a38;
    --text: #d7dce3;
    --text-dim: #8992a3;
    --accent: #5fb3ff;
    --ok: #4fd67a;
    --warn: #f2b93d;
    --error: #ef5a6f;
    --mono: "Cascadia Code", "Consolas", "SFMono-Regular", Menlo, monospace;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;
    background: var(--bg);
    color: var(--text);
    font-family: var(--mono);
    font-size: 14px;
    line-height: 1.5;
    padding: 24px;
}

header {
    max-width: 1200px;
    margin: 0 auto 20px auto;
}

header code {
    color: var(--accent);
}

header h1 {
    margin: 0 0 4px 0;
    font-size: 20px;
    color: var(--text);
}

header p {
    margin: 0;
    color: var(--text-dim);
}

main {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.status-banner {
    border: 1px solid var(--panel-border);
    border-left-width: 4px;
    background: var(--panel);
    padding: 12px 16px;
    border-radius: 4px;
    font-weight: 600;
}

.status-banner.loading {
    border-left-color: var(--warn);
    color: var(--warn);
}

.status-banner.success {
    border-left-color: var(--ok);
    color: var(--ok);
}

.status-banner.error {
    border-left-color: var(--error);
    color: var(--error);
}

.panel {
    border: 1px solid var(--panel-border);
    background: var(--panel);
    border-radius: 6px;
    padding: 16px 18px;
}

.panel h2 {
    margin: 0 0 12px 0;
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-dim);
}

table.kv {
    width: 100%;
    border-collapse: collapse;
}

table.kv td {
    padding: 4px 0;
    vertical-align: top;
}

table.kv td.key {
    color: var(--text-dim);
    width: 40%;
    white-space: nowrap;
    padding-right: 12px;
}

table.kv td.val {
    color: var(--text);
    word-break: break-word;
}

.badge {
    display: inline-block;
    padding: 1px 8px;
    border-radius: 999px;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.03em;
}

.badge.valid {
    background: rgba(79, 214, 122, 0.15);
    color: var(--ok);
}

.badge.invalid {
    background: rgba(239, 90, 111, 0.15);
    color: var(--error);
}

.note {
    color: var(--text-dim);
    font-size: 12px;
    margin-top: 10px;
}

.error-text {
    color: var(--error);
    white-space: pre-wrap;
}

table.checks {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
}

table.checks th,
table.checks td {
    text-align: left;
    padding: 6px 10px;
    border-bottom: 1px solid var(--panel-border);
}

table.checks th {
    color: var(--text-dim);
    font-weight: 600;
    text-transform: uppercase;
    font-size: 11px;
    letter-spacing: 0.05em;
}

td.pass {
    color: var(--ok);
}

td.fail-expected {
    color: var(--warn);
}

footer {
    max-width: 1200px;
    margin: 24px auto 0 auto;
    color: var(--text-dim);
    font-size: 12px;
}

/* --------------------------------------------------------------------- */
/* Viewer toolbar, canvas, legend, progress - additions for the WebGPU   */
/* viewer milestone. Diagnostic-page styles above are unchanged.         */
/* --------------------------------------------------------------------- */

.toolbar {
    display: flex;
    flex-wrap: wrap;
    align-items: end;
    gap: 16px;
    border: 1px solid var(--panel-border);
    background: var(--panel);
    border-radius: 6px;
    padding: 12px 16px;
}

.toolbar-field {
    display: flex;
    flex-direction: column;
    gap: 4px;
    font-size: 12px;
    color: var(--text-dim);
}

.toolbar-field select {
    font-family: var(--mono);
    font-size: 13px;
    background: var(--bg);
    color: var(--text);
    border: 1px solid var(--panel-border);
    border-radius: 4px;
    padding: 6px 8px;
}

.view-toggle {
    display: flex;
    gap: 12px;
    align-items: center;
    border: 1px solid var(--panel-border);
    border-radius: 4px;
    padding: 6px 12px 8px 12px;
    margin: 0;
}

.view-toggle legend {
    font-size: 11px;
    color: var(--text-dim);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 0 4px;
}

.view-toggle label {
    font-size: 13px;
    display: flex;
    align-items: center;
    gap: 4px;
}

.render-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-left: auto;
}

.render-controls button,
#btn-fullscreen {
    font-family: var(--mono);
    font-size: 13px;
    background: var(--bg);
    color: var(--text);
    border: 1px solid var(--panel-border);
    border-radius: 4px;
    padding: 7px 12px;
    cursor: pointer;
}

.render-controls button:hover:not(:disabled) {
    border-color: var(--accent);
    color: var(--accent);
}

.render-controls button:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.enhanced-notice {
    color: var(--warn);
    font-size: 12px;
    min-height: 1em;
}

.generation-progress {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 12px;
    color: var(--text-dim);
}

.generation-progress-track {
    flex: 1;
    height: 6px;
    background: var(--bg);
    border: 1px solid var(--panel-border);
    border-radius: 999px;
    overflow: hidden;
}

.generation-progress-bar {
    height: 100%;
    width: 0%;
    background: var(--accent);
    transition: width 0.15s ease-out;
}

.canvas-container {
    position: relative;
    width: 100%;
    aspect-ratio: 16 / 9;
    min-height: 320px;
    max-height: 70vh;
    background: #0b0f16;
    border: 1px solid var(--panel-border);
    border-radius: 6px;
    overflow: hidden;
}

#gpu-canvas {
    display: block;
    width: 100%;
    height: 100%;
    touch-action: none;
}

.status-line {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 20px;
    font-size: 12px;
    color: var(--text-dim);
}

.status-line strong {
    color: var(--text);
}

.legend p {
    margin: 0 0 6px 0;
}

.diagnostics summary,
.legacy-diagnostics summary,
.diag-log-wrap summary {
    cursor: pointer;
    color: var(--text-dim);
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    padding: 2px 0;
}

.diagnostics[open] summary,
.legacy-diagnostics[open] summary {
    margin-bottom: 12px;
}

.legacy-diagnostics,
.diag-log-wrap {
    margin-top: 16px;
    border-top: 1px solid var(--panel-border);
    padding-top: 12px;
}

.diag-log {
    max-height: 160px;
    overflow-y: auto;
    font-size: 12px;
    color: var(--text-dim);
    background: var(--bg);
    border: 1px solid var(--panel-border);
    border-radius: 4px;
    padding: 8px 10px;
    margin-top: 8px;
}

.compat-message h2 {
    margin: 0 0 8px 0;
    font-size: 13px;
    color: var(--error);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.compat-message p {
    margin: 0;
    color: var(--text);
}

/* --------------------------------------------------------------------- */
/* Scientific Breakdown panel                                            */
/* --------------------------------------------------------------------- */

.scientific-breakdown summary {
    cursor: pointer;
    color: var(--text-dim);
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    padding: 2px 0;
}

.scientific-breakdown[open] summary {
    margin-bottom: 12px;
}

.what-to-notice {
    display: flex;
    flex-direction: column;
    gap: 4px;
    margin-bottom: 16px;
    padding: 10px 14px;
    border-left: 3px solid var(--accent);
    background: rgba(95, 179, 255, 0.07);
    border-radius: 0 4px 4px 0;
    font-size: 13px;
    color: var(--text);
}

.what-to-notice-label {
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--accent);
}

.science-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 16px;
    align-items: start;
}

.science-subsection {
    border: 1px solid var(--panel-border);
    border-radius: 6px;
    padding: 12px 14px;
    background: rgba(255, 255, 255, 0.015);
}

.science-subsection h3 {
    margin: 0 0 8px 0;
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-dim);
}

.science-subsection p {
    margin: 0 0 8px 0;
    font-size: 13px;
    line-height: 1.5;
}

.science-subsection p:last-child {
    margin-bottom: 0;
}

/* Label always stacked above value, at every viewport width. A two-column
   "label | value" split was tried and reverted: with labels ranging from
   "Basis" to "Raw density range (this sample)" to "Angular nodal geometry",
   any fixed column ratio either wastes space on short labels or squeezes
   long ones - a fixed "auto 1fr" layout with nowrap labels (the original
   version of this rule) squeezed values into an unreadably narrow column,
   and a "minmax(140px, 45%) 1fr" side-by-side variant at wider widths had
   the same problem in the other direction. Stacking avoids the whole class
   of bug and reads cleanly at any card width. */
.science-dl {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2px 12px;
    margin: 0 0 10px 0;
}

.science-dl dt {
    color: var(--text-dim);
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.science-dl dd {
    margin: 0 0 6px 0;
    color: var(--text);
    font-size: 13px;
    overflow-wrap: break-word;
}

.science-dl dd:last-child {
    margin-bottom: 0;
}

.equation {
    margin: 0 0 10px 0;
    padding: 8px 10px;
    border: 1px solid var(--panel-border);
    border-radius: 4px;
    background: var(--bg);
    overflow-x: auto;
}

.equation math {
    display: block;
    color: var(--text);
    font-size: 15px;
}

.equation-plain {
    margin-top: 6px;
    padding-top: 6px;
    border-top: 1px dashed var(--panel-border);
    font-size: 12px;
    color: var(--text-dim);
    white-space: pre-wrap;
}

@media (max-width: 640px) {
    .toolbar {
        flex-direction: column;
        align-items: stretch;
    }
    .render-controls {
        margin-left: 0;
        justify-content: space-between;
    }
    .canvas-container {
        aspect-ratio: 4 / 3;
    }
}