:root {
    /* App chrome (dark) */
    --bg: #14161a;
    --panel: #1e2127;
    --panel-2: #23262e;
    --fg: #e6e8eb;
    --muted: #9aa1ac;
    --border: #2b2f37;

    /* Game palette — from legacy/booklet.py */
    --cinnabar: #e64322;   /* card frame / number */
    --eucalyptus: #2fae5e; /* verifier number chip */
    --marigold: #b77f39;   /* difficulty gears */
    --deluge: #7d7497;     /* solution accent */
    --smoke: #f2f2f2;

    /* Symbol colours — SYMBOLS_PROP */
    --sym-lozenge: #2da75a;
    --sym-pound: #ef9b1a;
    --sym-slash: #54aad0;
    --sym-currency: #7c64a4;

    /* Code-digit colours (blue / yellow / purple) */
    --code-blue: #4c8dde;
    --code-yellow: #d8a72a;
    --code-purple: #9a6fc0;

    --ok: #4caf7d;
    --error: #e06c75;

    --radius: 10px;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    line-height: 1.5;
    color: var(--fg);
    background: var(--bg);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

a { color: var(--sym-slash); }

.muted { color: var(--muted); }

/* ---------- Header / nav ---------- */

.app-header {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 0.75rem 1.5rem;
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border);
    background: linear-gradient(180deg, #181b21, var(--bg));
}

.app-title {
    margin: 0;
    font-size: 1.25rem;
    letter-spacing: 0.02em;
}
.app-title::before {
    content: "⚙";
    color: var(--cinnabar);
    margin-right: 0.4rem;
}

.app-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 0.25rem 1rem;
}

.app-nav a {
    color: var(--muted);
    text-decoration: none;
    padding: 0.2rem 0.1rem;
    border-bottom: 2px solid transparent;
}
.app-nav a:hover { color: var(--fg); }
.app-nav a.is-active {
    color: var(--fg);
    border-bottom-color: var(--cinnabar);
}

/* ---------- Layout ---------- */

#view {
    flex: 1;
    width: 100%;
    max-width: 56rem;
    margin: 0 auto;
    padding: 1.5rem;
}

.view-title { margin: 0 0 0.25rem; font-size: 1.4rem; }
.view-intro { margin: 0 0 1.25rem; }
.loading { padding: 2rem 0; }

.panel {
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.25rem;
    margin-bottom: 1.25rem;
}

.prose h3 { margin-top: 0; }
.prose .disclaimer { font-style: italic; color: var(--muted); }

/* ---------- Forms ---------- */

.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(11rem, 1fr));
    gap: 1rem;
}

.field {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
}
.field-label { font-weight: 600; font-size: 0.9rem; }
.field-hint { font-size: 0.78rem; }

.field input,
.field select {
    font: inherit;
    color: var(--fg);
    background: var(--panel-2);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.5rem 0.6rem;
    width: 100%;
}
.field input:focus,
.field select:focus {
    outline: 2px solid var(--sym-slash);
    outline-offset: 1px;
    border-color: transparent;
}

.field--error input,
.field--error select {
    border-color: var(--error);
    background: rgba(224, 108, 117, 0.08);
}

.form-actions {
    margin-top: 1.1rem;
    display: flex;
    gap: 0.75rem;
}

.btn {
    font: inherit;
    font-weight: 600;
    cursor: pointer;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.55rem 1.1rem;
    background: var(--panel-2);
    color: var(--fg);
}
.btn:hover { border-color: var(--muted); }
.btn:disabled { opacity: 0.6; cursor: progress; }

.btn-primary {
    background: var(--cinnabar);
    border-color: var(--cinnabar);
    color: #fff;
}
.btn-primary:hover { filter: brightness(1.08); border-color: var(--cinnabar); }

.btn-reveal { background: var(--deluge); border-color: var(--deluge); color: #fff; }
.btn-reveal:hover { filter: brightness(1.1); border-color: var(--deluge); }

/* ---------- Puzzle board ---------- */

.puzzle-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem 1rem;
    font-size: 0.85rem;
    margin-bottom: 1rem;
}
.puzzle-meta span { white-space: nowrap; }

.verifier-board {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 0.75rem;
}

.verifier-row {
    display: flex;
    align-items: center;
    gap: 0.85rem;
    background: var(--smoke);
    color: #1a1a1a;
    border: 2px solid var(--cinnabar);
    border-radius: 12px;
    padding: 0.6rem 0.85rem;
}

.verifier-letter {
    flex: 0 0 auto;
    width: 2.1rem;
    height: 2.1rem;
    display: grid;
    place-items: center;
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--cinnabar);
    border: 2px solid var(--cinnabar);
    border-radius: 50%;
    background: #fff;
}
.verifier-letter--sm {
    width: 1.6rem;
    height: 1.6rem;
    font-size: 0.85rem;
    border-width: 1.5px;
}

.verifier-number {
    flex: 0 0 auto;
    min-width: 2.1rem;
    height: 2.1rem;
    padding: 0 0.5rem;
    display: grid;
    place-items: center;
    font-weight: 700;
    color: #fff;
    background: var(--eucalyptus);
    border-radius: 8px;
}

.checkcard-box {
    margin-left: auto;
    position: relative;
    flex: 0 0 auto;
    min-width: 3rem;
    padding: 0.45rem 0.7rem 0.4rem;
    display: grid;
    place-items: center;
    background: #fff;
    border: 2px solid var(--cinnabar);
    border-radius: 8px;
}
.checkcard-symbol {
    position: absolute;
    top: -0.7rem;
    right: -0.55rem;
    width: 1.35rem;
    height: 1.35rem;
    display: grid;
    place-items: center;
    font-weight: 700;
    font-size: 0.9rem;
    color: #fff;
    background: var(--cinnabar);
    border-radius: 50%;
}
.checkcard-number {
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--cinnabar);
    letter-spacing: 0.02em;
}

/* Symbol badge tinted to the chosen symbol (SYMBOLS_PROP colours). */
.board--lozenge .checkcard-symbol { background: var(--sym-lozenge); }
.board--pound .checkcard-symbol { background: var(--sym-pound); }
.board--slash .checkcard-symbol { background: var(--sym-slash); }
.board--currency .checkcard-symbol { background: var(--sym-currency); }

.puzzle-actions { margin-top: 1.25rem; }

/* ---------- Solution reveal ---------- */

.solution-region { margin-top: 1rem; }
.solution-panel {
    border: 1px dashed var(--deluge);
    border-radius: var(--radius);
    padding: 1rem;
    background: var(--panel-2);
}

.solution-code {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    margin: 0 0 0.75rem;
}
.solution-code-label {
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-size: 0.75rem;
    color: var(--muted);
}

.code-digit,
.code-chip .code-digit {
    display: inline-grid;
    place-items: center;
    width: 1.9rem;
    height: 1.9rem;
    font-weight: 700;
    color: #fff;
    border-radius: 6px;
}
.code-digit--blue { background: var(--code-blue); }
.code-digit--yellow { background: var(--code-yellow); }
.code-digit--purple { background: var(--code-purple); }
.code-digit--plain { background: var(--muted); }

.criteria-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 0.45rem;
}
.criteria-list li {
    display: flex;
    align-items: center;
    gap: 0.6rem;
}
.criteria-text { font-variant-caps: small-caps; }

/* ---------- Solve table ---------- */

.solve-summary { margin-bottom: 0.85rem; }
.empty-state { color: var(--muted); }

.table-wrap { overflow-x: auto; }
.solve-table {
    width: 100%;
    border-collapse: collapse;
}
.solve-table th,
.solve-table td {
    text-align: left;
    padding: 0.55rem 0.6rem;
    border-bottom: 1px solid var(--border);
    vertical-align: top;
}
.solve-table th {
    font-size: 0.78rem;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--muted);
}
.cell-code { width: 7rem; }
.code-chip { display: inline-flex; gap: 0.25rem; }

.combo-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 0.4rem;
}
.combo {
    display: flex;
    flex-wrap: wrap;
    gap: 0.3rem;
}
.combo-tag {
    font-size: 0.8rem;
    font-variant-caps: small-caps;
    background: var(--panel-2);
    border: 1px solid var(--border);
    border-radius: 999px;
    padding: 0.1rem 0.55rem;
}

/* ---------- Play ---------- */

.panel-title { margin: 0 0 0.85rem; font-size: 1.1rem; }

/* Top row: verifiers (left, fluid) beside the deduction grid (right, content
   width). The test + history sections sit full-width below. */
.play-top {
    display: grid;
    grid-template-columns: minmax(0, 2fr) minmax(0, 1fr);
    gap: 1.25rem;
    align-items: start;
    margin-bottom: 1.25rem;
}
.play-top > .panel { margin-bottom: 0; }

/* A more compact board in Play (scoped so Generate keeps its larger sizing). */
.view-play .verifier-board { gap: 0.5rem; }
.view-play .verifier-row {
    gap: 0.6rem;
    padding: 0.4rem 0.6rem;
    border-radius: 10px;
}
.view-play .verifier-letter {
    width: 1.7rem;
    height: 1.7rem;
    font-size: 0.95rem;
}
.view-play .verifier-number {
    min-width: 1.7rem;
    height: 1.7rem;
    font-size: 0.9rem;
}
.view-play .checkcard-box {
    min-width: 2.5rem;
    padding: 0.35rem 0.55rem 0.3rem;
}
.view-play .checkcard-number { font-size: 1rem; }
.view-play .candidate-list { margin-top: 0.4rem; padding-top: 0.4rem; }
.view-play .candidate-tag { font-size: 0.72rem; padding: 0.05rem 0.45rem; }

@media (max-width: 720px) {
    .play-top { grid-template-columns: 1fr; }
}

/* Verifier row carrying its candidate-criteria menu (Play). The menu wraps to
   its own line below the letter/number/check-card. */
.verifier-row--annotated { flex-wrap: wrap; }
.candidate-list {
    flex-basis: 100%;
    list-style: none;
    margin: 0.5rem 0 0;
    padding: 0.5rem 0 0;
    border-top: 1px dashed rgba(26, 26, 26, 0.18);
    display: flex;
    flex-wrap: wrap;
    gap: 0.3rem;
}
.candidate-tag {
    font-size: 0.78rem;
    font-variant-caps: small-caps;
    color: #2a2a2a;
    background: rgba(0, 0, 0, 0.05);
    border: 1px solid rgba(26, 26, 26, 0.18);
    border-radius: 999px;
    padding: 0.1rem 0.55rem;
}

.rounds-counter strong { color: var(--fg); font-size: 1.05rem; }

.round-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 1.25rem;
    align-items: flex-start;
}

/* Three coloured digit selects acting as one code input. Scoped under
   .code-picker so these outrank the generic `.field select` styling. */
.code-picker { display: inline-flex; gap: 0.4rem; }
.code-picker .code-select {
    font: inherit;
    font-weight: 700;
    color: #fff;
    width: 2.8rem;
    text-align: center;
    border: none;
    border-radius: 8px;
    padding: 0.45rem 0.4rem;
    cursor: pointer;
    appearance: none;
}
.code-picker .code-select:focus {
    outline: 2px solid var(--fg);
    outline-offset: 2px;
    border-color: transparent;
}
.code-picker .code-select option { color: #1a1a1a; background: #fff; }
.code-picker .code-select--blue { background: var(--code-blue); }
.code-picker .code-select--yellow { background: var(--code-yellow); }
.code-picker .code-select--purple { background: var(--code-purple); }

.letter-chips { display: flex; flex-wrap: wrap; gap: 0.4rem; }
.letter-chip {
    font: inherit;
    font-weight: 700;
    cursor: pointer;
    width: 2.2rem;
    height: 2.2rem;
    display: grid;
    place-items: center;
    color: var(--fg);
    background: var(--panel-2);
    border: 2px solid var(--border);
    border-radius: 50%;
}
.letter-chip:hover:not(:disabled) { border-color: var(--muted); }
.letter-chip.is-selected {
    color: #fff;
    background: var(--eucalyptus);
    border-color: var(--eucalyptus);
}
.letter-chip:disabled { opacity: 0.45; cursor: not-allowed; }
/* Already queried on the current code this round — locked, shown as done. */
.letter-chip.is-asked {
    opacity: 1;
    cursor: default;
    color: var(--eucalyptus);
    background: rgba(47, 174, 94, 0.16);
    border-color: var(--eucalyptus);
    border-style: dashed;
}

.field-hint--error { color: var(--error); }

/* Deduction grid — manual scratchpad of digits 5→1 per colour. */
.grid-hint { margin: 0 0 0.85rem; }
.deduction-grid {
    display: grid;
    grid-template-columns: repeat(3, 3.2rem);
    gap: 0.45rem;
    width: max-content;
    background: var(--smoke);
    border: 2px solid var(--eucalyptus);
    border-radius: 16px;
    padding: 0.8rem;
}
.grid-cell {
    position: relative;
    font: inherit;
    font-weight: 800;
    font-size: 1.25rem;
    height: 2.8rem;
    display: grid;
    place-items: center;
    cursor: pointer;
    background: #fff;
    border: 2px solid currentColor;
    border-radius: 10px;
    overflow: hidden;
}
.grid-cell--blue { color: var(--code-blue); }
.grid-cell--yellow { color: var(--code-yellow); }
.grid-cell--purple { color: var(--code-purple); }
.grid-cell:hover { background: #f3f3f3; }
.grid-cell:focus-visible { outline: 2px solid var(--fg); outline-offset: 2px; }

/* Crossed-off: dim the digit and draw a diagonal strike. */
.grid-cell.is-ruled-out { opacity: 0.6; }
.grid-cell.is-ruled-out::after {
    content: "";
    position: absolute;
    left: -12%;
    right: -12%;
    top: 50%;
    height: 3px;
    background: var(--cinnabar);
    transform: rotate(-45deg);
    transform-origin: center;
}

/* Free-text scratchpad for deductions the digit grid can't express. */
.grid-notes-field {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    margin-top: 1rem;
}
.grid-notes {
    font: inherit;
    color: var(--fg);
    background: var(--panel-2);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.5rem 0.6rem;
    width: 100%;
    min-height: 4.5rem;
    resize: vertical;
}
.grid-notes:focus {
    outline: 2px solid var(--sym-slash);
    outline-offset: 1px;
    border-color: transparent;
}

.round-divider { flex: 1 1 auto; }

.verifier-number--sm {
    min-width: 1.6rem;
    height: 1.6rem;
    font-size: 0.8rem;
}

/* Round history header: title on the left, the running counts on the right. */
.history-head {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    justify-content: space-between;
    gap: 0.4rem 1rem;
    margin-bottom: 0.85rem;
}
.history-head .panel-title { margin: 0; }
.history-counts {
    display: flex;
    flex-wrap: wrap;
    gap: 0.3rem 1rem;
    font-size: 0.85rem;
}
.history-counts strong { color: var(--fg); }

/* Round history grid: rounds × verifier letters. */
.history-table { width: 100%; border-collapse: collapse; }
.history-table th,
.history-table td {
    padding: 0.4rem 0.5rem;
    border-bottom: 1px solid var(--border);
    text-align: center;
}
.history-table th {
    font-size: 0.78rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--muted);
}
.hist-num { width: 2rem; }

/* History header letters are popover triggers recalling the verifier's criteria. */
.hist-letter-btn {
    font: inherit;
    font-weight: 700;
    color: var(--muted);
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.1rem 0.35rem;
    border-radius: 6px;
    text-decoration: underline dotted;
    text-underline-offset: 3px;
}
.hist-letter-btn:hover { color: var(--fg); }
.hist-letter-btn:focus-visible { outline: 2px solid var(--sym-slash); outline-offset: 1px; }

.verifier-popover {
    position: fixed;
    inset: auto;          /* override the UA popover centring so top/left apply */
    margin: 0;
    max-width: 16rem;
    background: var(--panel-2);
    color: var(--fg);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 0.7rem 0.8rem;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.45);
}
.verifier-popover-head {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.45rem;
}
.verifier-popover-title {
    margin: 0 0 0.4rem;
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--muted);
}
.candidate-list--pop {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    gap: 0.3rem;
}
.candidate-list--pop .candidate-tag {
    color: var(--fg);
    background: var(--panel);
    border-color: var(--border);
}
.hist-code { width: 7rem; text-align: left; }
.hist-cell { font-weight: 700; }
.hist-pass { color: var(--ok); background: rgba(76, 175, 125, 0.12); }
.hist-fail { color: var(--error); background: rgba(224, 108, 117, 0.12); }

.guess-form { border-color: var(--deluge); }
.guess-miss { color: var(--error); font-weight: 600; }

.end-panel--won { border-color: var(--ok); }
.end-panel--revealed { border-color: var(--deluge); }

/* Visually hidden but available to screen readers. */
.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;
}

/* ---------- Errors ---------- */

.error-panel {
    border-color: var(--error);
    background: rgba(224, 108, 117, 0.07);
}
.error-panel h2,
.error-panel h3 { margin-top: 0; color: var(--error); }

/* ---------- Footer ---------- */

.app-footer {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--border);
    font-size: 0.85rem;
    color: var(--muted);
}
.app-footer a { color: var(--sym-slash); }
.app-footer .disclaimer { font-style: italic; }

/* ---------- Mobile ---------- */

@media (max-width: 540px) {
    .app-header { flex-direction: column; align-items: flex-start; }
    .verifier-row { gap: 0.6rem; padding: 0.55rem 0.6rem; }
    .verifier-letter { width: 1.9rem; height: 1.9rem; font-size: 1rem; }
    .checkcard-box { min-width: 2.6rem; }
}