:root {
    --gear-ink: #1f2937;
    --gear-muted: #64748b;
    --gear-line: #d9e1ea;
    --gear-soft: #f5f7fb;
    --gear-blue: #2563eb;
    --gear-teal: #0f766e;
    --gear-orange: #ea580c;
    --gear-yellow: #f59e0b;
}

body,
* {
    font-family: "Noto Sans KR", sans-serif !important;
}

mjx-container,
mjx-container * {
    font-family: MJXZERO, MJXTEX, "Noto Sans KR", sans-serif !important;
}

mjx-container {
    line-height: 1.2;
}

body {
    background:
        radial-gradient(900px 520px at 14% -12%, rgba(37, 99, 235, 0.11), transparent 58%),
        radial-gradient(780px 480px at 92% 4%, rgba(15, 118, 110, 0.10), transparent 54%),
        var(--bg-page, #faf9f6);
    color: var(--text-main, #1f2937);
}

.page-shell {
    max-width: 1200px;
    margin: 0 auto;
    padding: 48px 24px 72px;
}

.gear-header {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 20px;
    align-items: end;
    margin-bottom: 24px;
}

.gear-header h1 {
    margin-bottom: 10px;
    line-height: 1.18;
}

.gear-header p {
    max-width: 760px;
    word-break: keep-all;
}

.header-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 9px 13px;
    border: 1px solid var(--border-light, #e5e7eb);
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.78);
    box-shadow: var(--shadow-sm, 0 1px 2px rgba(0, 0, 0, 0.05));
    color: var(--gear-muted);
    font-size: 0.86rem;
    font-weight: 700;
    white-space: nowrap;
}

.tab-bar {
    display: flex;
    width: fit-content;
    max-width: 100%;
    padding: 5px;
    gap: 5px;
    border: 1px solid var(--border-light, #e5e7eb);
    border-radius: 16px;
    background: rgba(255, 255, 255, 0.82);
    box-shadow: var(--shadow-sm, 0 1px 2px rgba(0, 0, 0, 0.05));
    overflow-x: auto;
    margin-bottom: 18px;
}

.tab-button {
    display: inline-flex;
    align-items: center;
    gap: 9px;
    border: 0;
    border-radius: 12px;
    padding: 11px 16px;
    background: transparent;
    color: var(--gear-muted);
    font-size: 0.95rem;
    font-weight: 800;
    cursor: pointer;
    white-space: nowrap;
    transition: background 180ms ease, color 180ms ease, box-shadow 180ms ease;
}

.tab-button svg {
    width: 18px;
    height: 18px;
    flex: 0 0 auto;
}

.tab-button.active {
    background: var(--gear-ink);
    color: #ffffff;
    box-shadow: 0 10px 22px rgba(31, 41, 55, 0.18);
}

.scene {
    display: none;
}

.scene.active {
    display: block;
}

.simulator {
    display: grid;
    grid-template-columns: minmax(0, 1.45fr) minmax(310px, 0.8fr);
    gap: 18px;
    align-items: stretch;
}

.visual-panel,
.control-panel,
.math-panel {
    border: 1px solid var(--border-light, #e5e7eb);
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.92);
    box-shadow: var(--shadow-lg, 0 10px 15px rgba(0, 0, 0, 0.05));
}

.visual-panel {
    position: relative;
    overflow: hidden;
    min-height: 500px;
    display: flex;
    flex-direction: column;
}

.stage-head {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 14px;
    padding: 20px 22px 0;
    position: relative;
    z-index: 2;
}

.stage-head h2,
.control-panel h2 {
    margin: 0;
    color: var(--gear-ink);
    font-size: 1.16rem;
    line-height: 1.35;
}

.stage-head p {
    margin: 6px 0 0;
    color: var(--gear-muted);
    font-size: 0.92rem;
    line-height: 1.55;
    word-break: keep-all;
}

.scene-label {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    padding: 7px 10px;
    border-radius: 999px;
    background: var(--gear-soft);
    color: var(--gear-muted);
    font-size: 0.78rem;
    font-weight: 800;
    white-space: nowrap;
}

.gear-canvas {
    width: 100%;
    height: 430px;
    flex: 0 0 430px;
    display: block;
}

.canvas-note {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    padding: 0 18px 18px;
}

.metric {
    min-width: 0;
    border: 1px solid var(--gear-line);
    border-radius: 14px;
    background: #ffffff;
    padding: 12px;
}

.metric strong {
    display: block;
    color: var(--gear-ink);
    font-size: clamp(1rem, 2.2vw, 1.5rem);
    line-height: 1.15;
    white-space: nowrap;
}

.metric span {
    display: block;
    margin-top: 5px;
    color: var(--gear-muted);
    font-size: 0.76rem;
    font-weight: 700;
}

.control-panel {
    padding: 20px;
}

.control-panel h2 {
    margin-bottom: 14px;
}

.control-stack {
    display: grid;
    gap: 16px;
}

.control-group {
    border-top: 1px solid var(--gear-line);
    padding-top: 15px;
}

.control-group:first-child {
    border-top: 0;
    padding-top: 0;
}

.control-row {
    display: grid;
    gap: 9px;
}

.control-row + .control-row {
    margin-top: 15px;
}

.control-label {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    color: var(--gear-ink);
    font-size: 0.92rem;
    font-weight: 800;
}

.value-pill {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 76px;
    padding: 6px 9px;
    border-radius: 999px;
    background: var(--gear-soft);
    color: var(--gear-ink);
    font-size: 0.82rem;
    font-weight: 800;
    white-space: nowrap;
}

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

.number-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
}

.number-field {
    display: grid;
    gap: 7px;
    color: var(--gear-ink);
    font-size: 0.86rem;
    font-weight: 800;
}

.number-field.compact {
    margin-top: 12px;
}

.number-field input {
    width: 100%;
    min-height: 44px;
    border: 1px solid var(--gear-line);
    border-radius: 12px;
    background: #ffffff;
    color: var(--gear-ink);
    font-size: 1rem;
    font-weight: 800;
    padding: 0 12px;
}

.number-field input:focus {
    outline: none;
    border-color: var(--gear-blue);
    box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.12);
}

.button-row,
.button-grid {
    display: grid;
    gap: 8px;
}

.button-row {
    grid-template-columns: repeat(auto-fit, minmax(96px, 1fr));
}

.button-grid.two {
    grid-template-columns: repeat(2, 1fr);
}

.button-grid.four {
    grid-template-columns: repeat(4, 1fr);
}

.icon-button,
.preset-button,
.sign-button,
.step-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    min-height: 42px;
    border: 1px solid var(--gear-line);
    border-radius: 12px;
    background: #ffffff;
    color: var(--gear-ink);
    font-size: 0.86rem;
    font-weight: 800;
    cursor: pointer;
    transition: transform 150ms ease, border-color 150ms ease, background 150ms ease, color 150ms ease;
}

.icon-button {
    min-width: 44px;
    padding: 0;
}

.icon-button svg {
    width: 17px;
    height: 17px;
    flex: 0 0 auto;
}

.step-button {
    min-height: 58px;
    flex-direction: column;
    gap: 2px;
}

.step-button span {
    color: var(--gear-muted);
    font-size: 0.76rem;
}

.step-button b {
    font-size: 1.08rem;
}

.step-button.primary {
    border-color: rgba(37, 99, 235, 0.26);
    background: #eff6ff;
    color: var(--gear-blue);
}

.step-button.primary.orange {
    border-color: rgba(234, 88, 12, 0.26);
    background: #fff7ed;
    color: var(--gear-orange);
}

.icon-button:hover,
.preset-button:hover,
.sign-button:hover,
.step-button:hover {
    transform: translateY(-1px);
    border-color: #c4d0dc;
    background: var(--gear-soft);
}

.sign-button.active {
    border-color: var(--gear-ink);
    background: var(--gear-ink);
    color: #ffffff;
}

.formula-box {
    border-radius: 16px;
    background: linear-gradient(135deg, #f8fafc 0%, #eef6f5 100%);
    border: 1px solid var(--gear-line);
    padding: 15px;
}

.formula {
    color: var(--gear-ink);
    font-size: clamp(1rem, 1.8vw, 1.24rem);
    font-weight: 800;
    line-height: 1.45;
    word-break: keep-all;
}

#averageCenterFormulaTeeth,
#averageFormula {
    white-space: nowrap;
}

.formula .blue {
    color: var(--gear-blue);
}

.formula .teal {
    color: var(--gear-teal);
}

.formula .orange {
    color: var(--gear-orange);
}

.formula-caption {
    margin: 9px 0 0;
    color: var(--gear-muted);
    font-size: 0.86rem;
    line-height: 1.55;
    word-break: keep-all;
}

.readout-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 9px;
}

.readout {
    min-width: 0;
    border-radius: 14px;
    background: var(--gear-soft);
    padding: 12px;
}

.readout b {
    display: block;
    color: var(--gear-ink);
    font-size: 0.78rem;
    margin-bottom: 4px;
}

.readout span {
    display: block;
    color: var(--gear-muted);
    font-size: 0.86rem;
    font-weight: 800;
    overflow-wrap: anywhere;
}

.math-panel {
    margin-top: 18px;
    padding: 18px 20px;
}

.math-panel h2 {
    margin: 0 0 8px;
    font-size: 1.05rem;
    color: var(--gear-ink);
}

.math-panel p {
    margin: 0;
    color: var(--gear-muted);
    line-height: 1.65;
    word-break: keep-all;
}

@media (max-width: 980px) {
    .gear-header {
        grid-template-columns: 1fr;
    }

    .simulator {
        grid-template-columns: 1fr;
    }

    .visual-panel {
        min-height: 470px;
    }
}

@media (max-width: 640px) {
    .page-shell {
        padding: 34px 14px 56px;
    }

    .gear-header h1 {
        font-size: 2rem;
    }

    .stage-head {
        flex-direction: column;
        padding: 18px 16px 0;
    }

    .gear-canvas {
        height: 360px;
        flex-basis: 360px;
    }

    .canvas-note,
    .readout-grid,
    .number-grid,
    .button-grid.four,
    .button-grid.two {
        grid-template-columns: 1fr;
    }

    .control-panel,
    .math-panel {
        padding: 16px;
    }
}