/* === Reset & Base === */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html, body {
    overflow-x: hidden;
}

:root {
    --bg: #0f1117;
    --surface: #1a1d27;
    --surface-2: #242834;
    --border: #2e3345;
    --text: #e4e6f0;
    --text-dim: #8b8fa3;
    --primary: #5b8af5;
    --primary-hover: #7aa2ff;
    --success: #4caf7c;
    --error: #e05555;
    --warning: #e0a840;
    --highlight: #f0c040;
    --radius: 12px;
    --radius-sm: 8px;
}

html, body {
    height: 100%;
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

#app {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 72px 20px 20px;
}

.app-nav {
    position: fixed;
    top: 14px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
    display: flex;
    gap: 6px;
    padding: 6px;
    background: rgba(26, 29, 39, 0.94);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    box-shadow: 0 10px 28px rgba(0, 0, 0, 0.22);
    backdrop-filter: blur(10px);
}

.app-nav-link {
    color: var(--text-dim);
    text-decoration: none;
    font-size: 0.86rem;
    font-weight: 600;
    line-height: 1;
    padding: 9px 13px;
    border-radius: 6px;
    white-space: nowrap;
}

.app-nav-link:hover,
.app-nav-link.active {
    color: var(--text);
    background: var(--surface-2);
}

/* === Screens === */
.screen {
    display: none;
    width: 100%;
    max-width: min(600px, calc(100vw - 40px));
    animation: fadeIn 0.3s ease;
}

.screen.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* === Card === */
.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 36px;
    overflow: hidden;
    max-width: 100%;
}

.welcome-card {
    max-height: 90vh;
    overflow-y: auto;
}

h1 {
    font-size: 1.8rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 4px;
}

h2 {
    font-size: 1.4rem;
    font-weight: 600;
    text-align: center;
    margin-bottom: 16px;
}

h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 10px;
}

.subtitle {
    text-align: center;
    color: var(--text-dim);
    font-size: 0.95rem;
    margin-bottom: 24px;
}

/* === Info Boxes === */
.info-box {
    background: var(--surface-2);
    border-radius: var(--radius-sm);
    padding: 18px 20px;
    margin-bottom: 16px;
}

.info-box p {
    font-size: 0.9rem;
    color: var(--text-dim);
    margin-bottom: 8px;
}

.info-box p:last-child {
    margin-bottom: 0;
}

.example-note {
    font-size: 0.8rem !important;
    font-style: italic;
    color: var(--text-dim);
    opacity: 0.7;
    margin-top: 4px;
}

/* === Settings === */
.settings-row {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
    font-size: 0.9rem;
}

.settings-row label {
    min-width: 90px;
    color: var(--text-dim);
}

.settings-row select,
.settings-row input[type="range"] {
    flex: 1;
    min-width: 0;
}

select {
    background: var(--surface-2);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 6px 10px;
    font-size: 0.85rem;
    max-width: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
}

input[type="range"] {
    accent-color: var(--primary);
}

#voice-rate-label {
    color: var(--text-dim);
    min-width: 35px;
    text-align: right;
    font-size: 0.85rem;
}

/* === Buttons === */
.btn {
    display: inline-block;
    padding: 12px 32px;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s, opacity 0.2s;
}

.btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
    width: 100%;
    margin-top: 16px;
}

.btn-primary:hover:not(:disabled) {
    background: var(--primary-hover);
}

.btn-secondary {
    background: var(--surface-2);
    color: var(--text-dim);
    border: 1px solid var(--border);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--border);
}

.note {
    text-align: center;
    color: var(--text-dim);
    font-size: 0.8rem;
    margin-top: 12px;
}

/* === Ready Screen === */
.stimulus-card {
    text-align: center;
    min-height: 280px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.trial-counter {
    font-size: 0.85rem;
    color: var(--text-dim);
    margin-bottom: 24px;
    letter-spacing: 0.02em;
}

.ready-prompt {
    font-size: 1.1rem;
    color: var(--text);
    margin-bottom: 8px;
}

.level-info {
    font-size: 0.82rem;
    color: var(--primary);
    background: rgba(91, 138, 245, 0.1);
    border: 1px solid rgba(91, 138, 245, 0.2);
    border-radius: 6px;
    padding: 4px 14px;
    margin-bottom: 16px;
    letter-spacing: 0.02em;
}

/* === Stimulus Screen — Listening Indicator === */
.listening-indicator {
    position: relative;
    width: 100px;
    height: 100px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.pulse-ring {
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    border: 2px solid var(--primary);
    opacity: 0;
    animation: pulseRing 2s ease-out infinite;
}

.pulse-ring.delay-1 {
    animation-delay: 0.5s;
}

.pulse-ring.delay-2 {
    animation-delay: 1.0s;
}

@keyframes pulseRing {
    0% {
        transform: scale(0.5);
        opacity: 0.6;
    }
    100% {
        transform: scale(1.4);
        opacity: 0;
    }
}

.speaker-icon {
    position: relative;
    z-index: 1;
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    animation: breathe 1.5s ease-in-out infinite;
}

@keyframes breathe {
    0%, 100% { transform: scale(1); opacity: 0.85; }
    50% { transform: scale(1.08); opacity: 1; }
}

.listening-label {
    font-size: 1.2rem;
    font-weight: 500;
    color: var(--text-dim);
    animation: pulse 1.5s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 0.4; }
    50% { opacity: 1; }
}

/* === Response Screen === */
.response-card {
    text-align: center;
}

.response-card h2 {
    margin-bottom: 4px;
}

.highlight {
    color: var(--highlight);
    font-weight: 700;
}

.response-hint {
    font-size: 0.85rem;
    color: var(--text-dim);
    margin-bottom: 20px;
}

/* Response Slots */
.response-slots {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-bottom: 24px;
    flex-wrap: wrap;
}

.slot {
    width: 52px;
    height: 60px;
    background: var(--surface-2);
    border: 2px solid var(--border);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    font-weight: 600;
    font-variant-numeric: tabular-nums;
    transition: border-color 0.15s;
}

.slot.active {
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(91, 138, 245, 0.25);
}

.slot.filled {
    border-color: var(--text-dim);
}

/* Feedback highlighting (optional — toggled on settings) */
.slot.slot-correct {
    border-color: var(--success);
    background: rgba(76, 175, 124, 0.15);
    color: var(--success);
    box-shadow: 0 0 0 2px rgba(76, 175, 124, 0.25);
}

.slot.slot-incorrect {
    border-color: var(--error);
    background: rgba(224, 85, 85, 0.12);
    color: var(--error);
    box-shadow: 0 0 0 2px rgba(224, 85, 85, 0.2);
    position: relative;
    flex-direction: column;
    gap: 0;
    line-height: 1.1;
}

.slot-correct-hint {
    display: block;
    font-size: 0.7rem;
    color: var(--success);
    opacity: 0.85;
    font-weight: 500;
}

/* Toggle label for settings */
.toggle-label {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    font-size: 0.85rem;
    color: var(--text-dim);
}

.toggle-label input[type="checkbox"] {
    accent-color: var(--primary);
    width: 16px;
    height: 16px;
    cursor: pointer;
}

/* Number Pad */
.numpad {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
    max-width: 280px;
    margin: 0 auto 20px;
}

.numpad-btn {
    height: 56px;
    background: var(--surface-2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text);
    font-size: 1.3rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.15s, transform 0.1s;
    user-select: none;
    -webkit-user-select: none;
}

.numpad-btn:hover {
    background: var(--border);
}

.numpad-btn:active {
    transform: scale(0.95);
    background: var(--primary);
}

.numpad-clear {
    font-size: 0.85rem;
    color: var(--error);
}

.numpad-back {
    font-size: 1.1rem;
    color: var(--warning);
}

.response-actions {
    display: flex;
    gap: 10px;
}

.response-actions .btn {
    flex: 1;
}

.response-actions .btn-primary {
    margin-top: 0;
}

/* === Arithmetic Test === */
#arith-screen-results {
    max-width: min(980px, calc(100vw - 40px));
}

#arith-screen-response {
    max-width: min(680px, calc(100vw - 40px));
}

.arithmetic-response-card h2 {
    margin-top: 18px;
}

.timer-wrap {
    width: 100%;
    background: var(--surface-2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 12px 14px;
    margin-bottom: 10px;
}

.timer-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-dim);
    font-size: 0.86rem;
    margin-bottom: 8px;
}

.timer-row strong {
    color: var(--text);
    font-variant-numeric: tabular-nums;
}

.timer-track {
    width: 100%;
    height: 8px;
    background: var(--border);
    border-radius: 999px;
    overflow: hidden;
}

.timer-fill {
    height: 100%;
    width: 100%;
    background: var(--success);
    border-radius: 999px;
    transition: width 0.1s linear, background 0.2s ease;
}

.timer-fill.timer-low {
    background: var(--warning);
}

.question-fallback {
    background: rgba(224, 168, 64, 0.1);
    border: 1px solid rgba(224, 168, 64, 0.24);
    border-radius: var(--radius-sm);
    color: var(--text);
    font-size: 0.92rem;
    line-height: 1.5;
    padding: 12px 14px;
    margin-bottom: 14px;
    text-align: left;
}

.repeat-answer-grid {
    display: grid;
    grid-template-columns: 180px minmax(0, 1fr);
    gap: 12px;
    align-items: stretch;
    margin-bottom: 14px;
}

.repeat-btn {
    width: 100%;
    padding-left: 14px;
    padding-right: 14px;
}

.answer-box {
    display: flex;
    flex-direction: column;
    gap: 6px;
    text-align: left;
    color: var(--text-dim);
    font-size: 0.82rem;
    font-weight: 600;
}

.answer-box input {
    width: 100%;
    min-height: 48px;
    background: var(--surface-2);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 8px 12px;
    font-size: 1.25rem;
    font-weight: 600;
    font-variant-numeric: tabular-nums;
}

.answer-box input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(91, 138, 245, 0.24);
}

.item-feedback {
    min-height: 24px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.item-feedback.info {
    color: var(--primary);
}

.item-feedback.success {
    color: var(--success);
}

.item-feedback.error {
    color: var(--error);
}

.arithmetic-detail-table .question-cell {
    min-width: 300px;
    max-width: 420px;
    white-space: normal;
    line-height: 1.35;
}

/* === Results Screen === */
.results-card {
    max-height: 90vh;
    overflow-y: auto;
}

.results-card h1 {
    margin-bottom: 24px;
}

/* IQ Hero Card */
.iq-hero {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    background: linear-gradient(135deg, rgba(91, 138, 245, 0.12), rgba(76, 175, 124, 0.08));
    border: 1px solid rgba(91, 138, 245, 0.25);
    border-radius: var(--radius-sm);
    padding: 24px 20px;
    margin-bottom: 20px;
}

.iq-label {
    font-size: 0.78rem;
    color: var(--text-dim);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 8px;
}

.iq-score {
    font-size: 3.2rem;
    font-weight: 800;
    color: var(--primary);
    line-height: 1;
    margin-bottom: 6px;
}

.iq-classification {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 4px;
}

.iq-percentile {
    font-size: 0.85rem;
    color: var(--text-dim);
}

.results-summary {
    display: flex;
    gap: 12px;
    margin-bottom: 28px;
    flex-wrap: wrap;
}

.result-item {
    flex: 1;
    min-width: 140px;
    background: var(--surface-2);
    border-radius: var(--radius-sm);
    padding: 16px;
    text-align: center;
}

.result-label {
    display: block;
    font-size: 0.78rem;
    color: var(--text-dim);
    text-transform: uppercase;
    letter-spacing: 0.04em;
    margin-bottom: 6px;
}

.result-value {
    display: block;
    font-size: 1.3rem;
    font-weight: 700;
}

.result-value.big {
    font-size: 1.8rem;
    color: var(--primary);
}

/* Results by probe size */
.results-by-block {
    margin-bottom: 24px;
}

.block-result {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 14px;
    background: var(--surface-2);
    border-radius: 6px;
    margin-bottom: 6px;
    font-size: 0.88rem;
}

.block-result-label {
    color: var(--text-dim);
    min-width: 55px;
}

.block-result-bar {
    flex: 1;
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    margin: 0 14px;
    overflow: hidden;
}

.block-result-fill {
    height: 100%;
    background: var(--primary);
    border-radius: 3px;
    transition: width 0.5s ease;
}

.block-result-value {
    font-weight: 600;
    min-width: 90px;
    text-align: right;
    font-size: 0.82rem;
}

/* Trial detail table */
.trial-detail-table-wrap {
    margin-bottom: 24px;
    overflow-x: auto;
}

.trial-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.82rem;
}

.trial-table th {
    text-align: left;
    color: var(--text-dim);
    font-weight: 500;
    padding: 8px 8px;
    border-bottom: 1px solid var(--border);
    white-space: nowrap;
}

.trial-table td {
    padding: 7px 8px;
    border-bottom: 1px solid rgba(46, 51, 69, 0.4);
    white-space: nowrap;
}

.trial-table .mono {
    font-family: 'Consolas', 'Courier New', monospace;
    font-size: 0.85rem;
    letter-spacing: 0.04em;
}

.digit-correct {
    color: var(--success);
    font-weight: 700;
}

.digit-wrong {
    color: var(--error);
    font-weight: 600;
}

.digit-blank {
    color: var(--text-dim);
    opacity: 0.5;
}

/* Norm Table */
.norm-table {
    background: var(--surface-2);
    border-radius: var(--radius-sm);
    padding: 18px 20px;
    margin-bottom: 20px;
}

.norm-table table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.88rem;
}

.norm-table th {
    text-align: left;
    color: var(--text-dim);
    font-weight: 500;
    padding: 6px 10px;
    border-bottom: 1px solid var(--border);
}

.norm-table td {
    padding: 6px 10px;
    border-bottom: 1px solid rgba(46, 51, 69, 0.5);
}

.norm-note {
    font-size: 0.78rem;
    color: var(--text-dim);
    margin-top: 10px;
    line-height: 1.5;
}

/* Norm Submission */
.norm-submit-section {
    background: var(--surface-2);
    border-radius: var(--radius-sm);
    padding: 18px 20px;
    margin-bottom: 20px;
    border: 1px solid rgba(76, 175, 124, 0.2);
}

.norm-submit-section h3 {
    margin-bottom: 8px;
}

.norm-submit-desc {
    font-size: 0.85rem;
    color: var(--text-dim);
    margin-bottom: 14px;
}

.norm-submit-row {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
    font-size: 0.88rem;
}

.norm-submit-row label {
    color: var(--text-dim);
    white-space: nowrap;
}

.age-input,
.score-input {
    width: 100px;
    background: var(--bg);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 6px 10px;
    font-size: 0.88rem;
}

.btn-success {
    background: var(--success);
    color: #fff;
    width: 100%;
}

.btn-success:hover:not(:disabled) {
    background: #5bc48a;
}

.submit-status {
    margin-top: 10px;
    padding: 8px 12px;
    border-radius: 6px;
    font-size: 0.85rem;
    text-align: center;
}

.submit-status.info {
    background: rgba(91, 138, 245, 0.1);
    color: var(--primary);
}

.submit-status.success {
    background: rgba(76, 175, 124, 0.12);
    color: var(--success);
}

.submit-status.warning {
    background: rgba(224, 168, 64, 0.12);
    color: var(--warning);
}

.submit-status.error {
    background: rgba(224, 85, 85, 0.1);
    color: var(--error);
}

.results-actions {
    display: flex;
    gap: 10px;
}

.results-actions .btn {
    flex: 1;
}

.results-actions .btn-primary {
    margin-top: 0;
}

/* Discontinued Notice */
.discontinued-notice {
    background: rgba(224, 168, 64, 0.12);
    border: 1px solid rgba(224, 168, 64, 0.3);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    margin-bottom: 20px;
    font-size: 0.88rem;
    color: var(--warning);
    text-align: center;
}

/* Recalibration Results */
.recal-summary {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: var(--surface-2);
    border-radius: 6px;
    padding: 10px 14px;
    margin-bottom: 6px;
}

.recal-label {
    color: var(--text-dim);
    font-size: 0.88rem;
}

.recal-value {
    font-weight: 600;
    font-size: 0.88rem;
}

.recal-note {
    font-size: 0.78rem;
    color: var(--text-dim);
    line-height: 1.5;
    margin-bottom: 16px;
}

.recal-row {
    background: rgba(91, 138, 245, 0.04);
}

.recal-row td {
    font-style: italic;
}

/* === Responsive === */
@media (max-width: 480px) {
    #app {
        padding: 76px 14px 14px;
    }

    .app-nav {
        width: calc(100vw - 28px);
        justify-content: center;
    }

    .app-nav-link {
        flex: 1;
        text-align: center;
        padding-left: 8px;
        padding-right: 8px;
        font-size: 0.8rem;
    }

    .card {
        padding: 24px 18px;
    }

    .numpad {
        max-width: 240px;
    }

    .numpad-btn {
        height: 48px;
        font-size: 1.1rem;
    }

    .slot {
        width: 44px;
        height: 52px;
        font-size: 1.5rem;
    }

    .results-summary {
        flex-direction: column;
    }

    .trial-table {
        font-size: 0.75rem;
    }

    .repeat-answer-grid {
        grid-template-columns: 1fr;
    }

    .arithmetic-detail-table .question-cell {
        min-width: 220px;
    }
}