:root {
    color-scheme: dark;
    --ink: #eef7f3;
    --muted: #9caea7;
    --line: rgba(229, 241, 236, 0.14);
    --paper: #070d0b;
    --panel: #0d1714;
    --panel-strong: #14231f;
    --charcoal: #08100e;
    --primary: #148f80;
    --primary-dark: #0a685e;
    --primary-bright: #70dfca;
    --accent: #c76c35;
    --focus: #f2c94c;
    --glass: rgba(13, 23, 20, 0.82);
    --glass-strong: rgba(19, 33, 29, 0.92);
    --danger-bg: #3a1815;
    --danger-line: #a9503f;
    --danger-text: #ffc8ba;
    --success-bg: #123729;
    --success-text: #8ee6c4;
    --shadow: 0 22px 60px rgba(0, 0, 0, 0.42);
}

* {
    box-sizing: border-box;
}

html,
body {
    height: 100%;
    overflow: hidden;
}

body {
    margin: 0;
    background:
        linear-gradient(135deg, rgba(20, 143, 128, 0.13), transparent 38%),
        linear-gradient(315deg, rgba(199, 108, 53, 0.11), transparent 42%),
        var(--paper);
    color: var(--ink);
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    letter-spacing: 0;
}

button {
    font: inherit;
}

* {
    scrollbar-color: rgba(112, 223, 202, 0.36) rgba(255, 255, 255, 0.04);
}

button:focus-visible,
canvas:focus-visible,
a:focus-visible {
    outline: 3px solid var(--focus);
    outline-offset: 3px;
}

.app-shell {
    height: 100dvh;
    min-height: 0;
    display: grid;
    grid-template-rows: auto 1fr;
}

.topbar {
    min-height: 62px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    padding: 10px clamp(14px, 2.2vw, 28px);
    border-bottom: 1px solid var(--line);
    background: rgba(7, 13, 11, 0.88);
    backdrop-filter: blur(14px);
    box-shadow: 0 16px 44px rgba(0, 0, 0, 0.22);
    position: sticky;
    top: 0;
    z-index: 10;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    color: inherit;
    text-decoration: none;
    min-width: 0;
}

.brand-mark {
    width: 40px;
    height: 40px;
    display: block;
    flex: 0 0 auto;
    border-radius: 10px;
    box-shadow: 0 12px 28px rgba(0, 0, 0, 0.38), 0 0 0 1px rgba(242, 201, 76, 0.12);
}

.brand strong {
    display: block;
    font-size: 0.98rem;
    line-height: 1.05;
}

.brand small {
    display: block;
    color: var(--primary-bright);
    font-size: 0.78rem;
    margin-top: 3px;
    line-height: 1.2;
}

.topbar-actions {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 7px;
    flex-wrap: wrap;
}

.button {
    min-height: 36px;
    border: 1px solid transparent;
    border-radius: 8px;
    padding: 0 12px;
    cursor: pointer;
    transition: transform 160ms ease, background 160ms ease, border-color 160ms ease, opacity 160ms ease;
    white-space: nowrap;
    font-size: 0.9rem;
}

.button:hover {
    transform: translateY(-1px);
}

.button:disabled {
    cursor: not-allowed;
    opacity: 0.55;
    transform: none;
}

.button-primary {
    color: #ffffff;
    background: var(--primary);
    border-color: var(--primary);
    box-shadow: 0 10px 24px rgba(20, 143, 128, 0.24);
}

.button-primary:hover {
    background: var(--primary-dark);
}

.button-step {
    color: #ffffff;
    background: var(--accent);
    border-color: var(--accent);
}

.button-secondary {
    color: var(--ink);
    background: var(--panel);
    border-color: var(--line);
}

.button-secondary:hover {
    border-color: rgba(112, 223, 202, 0.42);
    background: var(--panel-strong);
}

.workspace {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(360px, 450px);
    min-height: 0;
    height: 100%;
}

.cube-stage {
    min-width: 0;
    min-height: 0;
    display: grid;
    grid-template-rows: auto minmax(0, 1fr) auto auto;
    padding: clamp(12px, 2vw, 24px);
    border-right: 1px solid var(--line);
    overflow: hidden;
    background:
        linear-gradient(145deg, rgba(20, 143, 128, 0.18), transparent 34%),
        linear-gradient(315deg, rgba(199, 108, 53, 0.13), transparent 40%),
        var(--charcoal);
}

.cube-canvas-wrap {
    position: relative;
    width: 100%;
    height: 100%;
    min-height: 0;
}

.stage-toolbar {
    display: grid;
    grid-template-columns: minmax(280px, 1fr) minmax(420px, 0.88fr);
    justify-content: space-between;
    align-items: start;
    gap: 14px;
    margin-bottom: 8px;
}

.stage-title {
    min-width: 0;
    padding-top: 2px;
}

.stage-tools {
    display: flex;
    align-items: flex-start;
    justify-content: flex-end;
    gap: 7px;
    flex-wrap: wrap;
    min-width: 0;
}

.view-controls {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 5px;
    flex-wrap: wrap;
}

.canvas-mode-toggle {
    display: flex;
    align-items: center;
    gap: 3px;
    padding: 3px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--glass);
}

.mode-button {
    min-width: 52px;
    min-height: 30px;
    padding: 0 9px;
    border: 0;
    border-radius: 6px;
    color: var(--muted);
    background: transparent;
    cursor: pointer;
    font-size: 0.78rem;
    font-weight: 850;
}

.mode-button:hover {
    color: var(--ink);
}

.mode-button[aria-pressed="true"] {
    color: #ffffff;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    box-shadow: 0 8px 18px rgba(20, 143, 128, 0.24);
}

.mode-button:disabled {
    cursor: not-allowed;
    opacity: 0.55;
}

.auto-orient-control {
    min-height: 32px;
    display: inline-flex;
    align-items: center;
    gap: 7px;
    padding: 0 10px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--glass);
    color: var(--ink);
    cursor: pointer;
    font-size: 0.78rem;
    font-weight: 850;
    white-space: nowrap;
}

.auto-orient-control input {
    width: 16px;
    height: 16px;
    margin: 0;
    accent-color: var(--primary-dark);
}

.playback-speed-control {
    min-height: 32px;
    display: grid;
    grid-template-columns: auto minmax(74px, 1fr) 38px;
    align-items: center;
    gap: 7px;
    padding: 0 10px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--glass);
    color: var(--ink);
    font-size: 0.78rem;
    font-weight: 850;
    white-space: nowrap;
}

.playback-speed-control input {
    width: 100%;
    min-width: 74px;
    accent-color: var(--primary-dark);
}

.playback-speed-control strong {
    font-size: 0.78rem;
    text-align: right;
}

.view-button {
    min-width: 40px;
    min-height: 32px;
    padding: 0 9px;
    border: 1px solid var(--line);
    border-radius: 8px;
    color: var(--ink);
    background: var(--glass);
    cursor: pointer;
    font-size: 0.78rem;
    font-weight: 800;
}

.view-button:hover {
    border-color: var(--primary);
}

.view-button:disabled {
    opacity: 0.55;
    cursor: not-allowed;
}

.eyebrow {
    margin: 0 0 5px;
    color: var(--primary-bright);
    font-size: 0.74rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

h1,
h2 {
    margin: 0;
    letter-spacing: 0;
}

h1 {
    max-width: 720px;
    font-size: clamp(1.55rem, 3.1vw, 3.55rem);
    line-height: 0.98;
}

h2 {
    font-size: 1rem;
    line-height: 1.2;
}

.move-meter {
    flex: 0 0 auto;
    display: grid;
    gap: 4px;
    min-width: 104px;
    padding: 8px 10px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--glass);
    text-align: right;
}

.move-meter span {
    color: var(--muted);
    font-size: 0.82rem;
}

.move-meter strong {
    font-size: 1.15rem;
}

#cubeCanvas {
    width: 100%;
    height: 100%;
    min-height: 0;
    display: block;
    cursor: grab;
    touch-action: none;
}

#cubeCanvas:active {
    cursor: grabbing;
}

body.canvas-paint-mode #cubeCanvas,
body.canvas-paint-mode #cubeCanvas:active {
    cursor: crosshair;
}

.canvas-alert {
    position: absolute;
    left: 50%;
    bottom: 14px;
    z-index: 2;
    width: min(calc(100% - 28px), 520px);
    transform: translateX(-50%);
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 42px;
    padding: 10px 14px;
    border: 1px solid var(--danger-line);
    border-radius: 8px;
    background: rgba(58, 24, 21, 0.94);
    color: var(--danger-text);
    box-shadow: 0 18px 40px rgba(0, 0, 0, 0.38), 0 0 0 1px rgba(255, 200, 186, 0.08);
    font-size: 0.9rem;
    font-weight: 900;
    line-height: 1.25;
    text-align: center;
    pointer-events: none;
}

.canvas-alert[hidden] {
    display: none;
}

.canvas-paint-dock {
    display: none;
}

.mobile-playback-controls {
    display: none;
}

.solution-strip {
    display: grid;
    gap: 8px;
    margin-top: 8px;
    min-height: 0;
}

.status-line {
    min-height: 22px;
    color: var(--muted);
    font-size: 0.92rem;
}

.move-list {
    min-height: 36px;
    max-height: 78px;
    display: flex;
    flex-wrap: wrap;
    align-content: flex-start;
    gap: 6px;
    overflow: auto;
    padding-right: 2px;
}

.move-chip {
    min-width: 36px;
    min-height: 30px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel-strong);
    color: var(--ink);
    font-weight: 750;
    font-size: 0.9rem;
    cursor: pointer;
}

.move-chip:hover {
    border-color: var(--primary);
}

.move-chip.is-done {
    color: #ffffff;
    background: var(--primary-dark);
    border-color: var(--primary-dark);
}

.move-chip.is-active {
    color: #ffffff;
    background: var(--accent);
    border-color: var(--accent);
}

.setup-panel {
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 8px;
    height: 100%;
    min-height: 0;
    padding: clamp(10px, 1.5vw, 16px);
    background: linear-gradient(180deg, var(--panel), #08100e);
    overflow-x: hidden;
    overflow-y: auto;
    overscroll-behavior: contain;
}

.site-credit {
    flex: 0 0 auto;
    margin-top: auto;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 4px;
    padding: 2px 4px 0;
    color: var(--muted);
    font-size: 0.76rem;
    line-height: 1.35;
    text-align: center;
}

.site-credit a {
    color: var(--primary-bright);
    font-weight: 800;
    text-decoration-thickness: 2px;
    text-underline-offset: 2px;
}

.panel-section {
    flex: 0 0 auto;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel);
    box-shadow: var(--shadow);
    padding: 12px;
    min-height: 0;
}

.panel-section.compact {
    padding-bottom: 14px;
}

.section-heading {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    align-items: end;
    margin-bottom: 10px;
}

.net-panel {
    display: grid;
    grid-template-rows: auto auto;
    overflow: visible;
}

.inline-heading {
    align-items: center;
}

.palette {
    display: grid;
    grid-template-columns: repeat(6, minmax(40px, 1fr));
    gap: 7px;
}

.palette-swatch {
    aspect-ratio: 1;
    min-height: 34px;
    border: 2px solid rgba(238, 247, 243, 0.44);
    border-radius: 8px;
    cursor: pointer;
    box-shadow: inset 0 0 0 4px rgba(255, 255, 255, 0.27), 0 8px 18px rgba(0, 0, 0, 0.22);
    position: relative;
}

.palette-swatch[data-valid="false"] {
    border-color: var(--danger-line);
}

.palette-swatch[aria-pressed="true"]::after {
    content: "";
    position: absolute;
    inset: -6px;
    border: 3px solid var(--accent);
    border-radius: 11px;
}

.swatch-count {
    position: absolute;
    right: 4px;
    bottom: 4px;
    min-width: 34px;
    min-height: 19px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0 5px;
    border: 1px solid rgba(238, 247, 243, 0.16);
    border-radius: 6px;
    background: rgba(7, 13, 11, 0.82);
    color: var(--ink);
    font-size: 0.67rem;
    font-weight: 900;
    line-height: 1;
    pointer-events: none;
}

.palette-swatch[data-valid="false"] .swatch-count {
    background: var(--danger-bg);
    color: var(--danger-text);
}

.cube-net {
    --net-gap: 6px;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    grid-template-areas:
        ". u . ."
        "l f r b"
        ". d . .";
    gap: 8px var(--net-gap);
    justify-content: center;
    align-items: start;
    width: min(100%, 390px);
    margin-inline: auto;
    padding: 2px 0 6px;
}

.net-face {
    width: 100%;
    display: grid;
    grid-template-rows: auto 1fr;
    gap: 4px;
    min-width: 0;
}

.net-face[data-face="U"] { grid-area: u; }
.net-face[data-face="R"] { grid-area: r; }
.net-face[data-face="F"] { grid-area: f; }
.net-face[data-face="D"] { grid-area: d; }
.net-face[data-face="L"] { grid-area: l; }
.net-face[data-face="B"] { grid-area: b; }

.net-face-heading {
    min-height: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 5px;
    color: var(--muted);
    font-size: 0.64rem;
    font-weight: 900;
    line-height: 1;
    text-align: center;
    text-transform: uppercase;
}

.net-face-heading span {
    color: var(--primary-bright);
}

.sticker-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: clamp(3px, 1vw, 5px);
}

.sticker {
    aspect-ratio: 1;
    min-width: 0;
    border: 2px solid #111816;
    border-radius: 7px;
    cursor: pointer;
    color: rgba(23, 33, 31, 0.72);
    font-size: 0.88rem;
    font-weight: 900;
    box-shadow: inset 0 0 0 3px rgba(255, 255, 255, 0.24);
}

.sticker.is-center {
    cursor: default;
    border-width: 3px;
}

.sticker:disabled {
    opacity: 1;
}

.validation-pill {
    min-width: 72px;
    min-height: 28px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0 9px;
    border-radius: 8px;
    background: var(--danger-bg);
    color: var(--danger-text);
    font-size: 0.78rem;
    font-weight: 800;
}

.validation-pill.is-valid {
    background: var(--success-bg);
    color: var(--success-text);
}

.is-busy .button,
.is-busy .move-chip,
.is-busy .mode-button,
.is-busy .sticker,
.is-busy .palette-swatch {
    pointer-events: none;
}

body.tutorial-open {
    overflow: hidden;
}

.tutorial-overlay {
    position: fixed;
    inset: 0;
    z-index: 40;
    background: rgba(0, 0, 0, 0.58);
    backdrop-filter: blur(3px);
}

.tutorial-overlay[hidden],
.tutorial-drawer[hidden],
.solve-guide-drawer[hidden] {
    display: none;
}

.tutorial-drawer,
.solve-guide-drawer {
    position: fixed;
    top: 0;
    right: 0;
    z-index: 41;
    height: 100dvh;
    display: grid;
    grid-template-rows: auto minmax(0, 1fr);
    background: var(--panel);
    border-left: 1px solid var(--line);
    box-shadow: -28px 0 70px rgba(0, 0, 0, 0.44);
}

.tutorial-drawer {
    width: min(760px, calc(100vw - 24px));
}

.solve-guide-drawer {
    width: min(680px, calc(100vw - 24px));
}

.tutorial-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    min-height: 72px;
    padding: 14px 16px;
    border-bottom: 1px solid var(--line);
    background: rgba(7, 13, 11, 0.94);
    backdrop-filter: blur(14px);
}

.tutorial-header h2 {
    font-size: 1.25rem;
}

.drawer-close {
    min-height: 36px;
    padding: 0 12px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel-strong);
    color: var(--ink);
    cursor: pointer;
    font-size: 0.88rem;
    font-weight: 800;
}

.drawer-close:hover {
    border-color: var(--primary);
}

.solve-guide-body {
    min-height: 0;
    display: grid;
    align-content: start;
    gap: 12px;
    padding: 14px;
    overflow: auto;
}

.solve-guide-intro,
.solve-guide-step {
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel);
    box-shadow: 0 14px 32px rgba(0, 0, 0, 0.28);
}

.solve-guide-intro {
    display: grid;
    gap: 9px;
    padding: 14px;
    background: var(--panel-strong);
}

.guide-label,
.guide-source {
    margin: 0;
    color: var(--muted);
    font-size: 0.78rem;
    line-height: 1.35;
}

.guide-label {
    color: var(--primary-bright);
    font-size: 0.72rem;
    font-weight: 900;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.guide-source a {
    color: var(--primary-bright);
    font-weight: 800;
}

.solve-guide-intro h3,
.solve-guide-step h3 {
    margin: 0;
    font-size: 1rem;
    line-height: 1.2;
}

.solve-guide-intro p,
.solve-guide-step p {
    margin: 0;
    color: var(--muted);
    font-size: 0.88rem;
    line-height: 1.45;
}

.guide-roadmap {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.guide-roadmap span {
    min-height: 28px;
    display: inline-flex;
    align-items: center;
    padding: 0 9px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel);
    color: var(--ink);
    font-size: 0.78rem;
    font-weight: 800;
}

.solve-guide-step {
    display: grid;
    grid-template-columns: 34px minmax(0, 1fr);
    gap: 11px;
    padding: 12px;
}

.guide-step-index {
    width: 34px;
    height: 34px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #ffffff;
    font-size: 0.9rem;
    font-weight: 900;
}

.solve-guide-step > div {
    display: grid;
    gap: 8px;
    min-width: 0;
}

.guide-list {
    display: grid;
    gap: 5px;
    margin: 0;
    padding-left: 18px;
    color: var(--muted);
    font-size: 0.86rem;
    line-height: 1.35;
}

.guide-algorithm-grid {
    display: grid;
    gap: 8px;
}

.guide-algorithm-card {
    display: grid;
    gap: 7px;
    padding: 9px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel-strong);
}

.guide-algorithm-card > span {
    color: var(--primary-bright);
    font-size: 0.76rem;
    font-weight: 900;
    text-transform: uppercase;
}

.guide-algorithm {
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
}

.guide-move-chip {
    min-width: 34px;
    min-height: 30px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel);
    color: var(--ink);
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 850;
}

.guide-move-chip:hover {
    border-color: var(--primary);
}

.practice-step {
    margin-bottom: 4px;
}

.tutorial-body {
    min-height: 0;
    display: grid;
    grid-template-columns: minmax(240px, 280px) minmax(0, 1fr);
    align-content: start;
    align-items: start;
    gap: 14px;
    padding: 14px;
    overflow: auto;
}

.tutorial-preview,
.tutorial-section {
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel);
    box-shadow: 0 14px 32px rgba(0, 0, 0, 0.28);
}

.tutorial-preview {
    grid-column: 1;
    grid-row: 1 / span 3;
    display: grid;
    gap: 10px;
    padding: 12px;
    position: sticky;
    top: 14px;
    z-index: 1;
}

.tutorial-section {
    grid-column: 2;
    min-width: 0;
}

#tutorialCanvas {
    width: 100%;
    aspect-ratio: 1;
    min-height: 0;
    display: block;
    border-radius: 8px;
    background:
        linear-gradient(145deg, rgba(20, 143, 128, 0.18), transparent 42%),
        linear-gradient(315deg, rgba(199, 108, 53, 0.13), transparent 42%),
        var(--charcoal);
}

.tutorial-move-name,
.tutorial-move-copy,
.tutorial-section-heading p,
.notation-card small {
    margin: 0;
}

.tutorial-move-name {
    font-size: 1rem;
    font-weight: 850;
}

.tutorial-move-copy {
    margin-top: 4px;
    color: var(--muted);
    font-size: 0.88rem;
    line-height: 1.35;
}

.tutorial-section {
    padding: 12px;
}

.tutorial-section-heading {
    display: flex;
    align-items: end;
    justify-content: space-between;
    gap: 14px;
    margin-bottom: 10px;
}

.tutorial-section-heading h3 {
    margin: 0;
    font-size: 0.96rem;
}

.tutorial-section-heading p {
    max-width: 220px;
    color: var(--muted);
    font-size: 0.78rem;
    line-height: 1.25;
    text-align: right;
}

.notation-list {
    display: grid;
    gap: 7px;
}

.compact-list,
.reference-list {
    grid-template-columns: repeat(1, minmax(0, 1fr));
}

.notation-card {
    width: 100%;
    min-height: 58px;
    display: grid;
    grid-template-columns: 54px minmax(0, 1fr);
    align-items: center;
    gap: 10px;
    padding: 8px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel-strong);
    color: var(--ink);
    cursor: pointer;
    text-align: left;
}

.notation-card:hover {
    border-color: var(--primary);
}

.notation-card.is-selected {
    border-color: var(--primary-bright);
    background: rgba(20, 143, 128, 0.18);
    box-shadow: inset 3px 0 0 var(--primary-bright);
}

.notation-symbol {
    min-height: 40px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #ffffff;
    font-weight: 900;
    font-size: 1rem;
}

.notation-card-copy {
    display: grid;
    gap: 3px;
    min-width: 0;
}

.notation-card-copy strong {
    font-size: 0.88rem;
    line-height: 1.15;
}

.notation-card small {
    color: var(--muted);
    font-size: 0.78rem;
    line-height: 1.3;
}

@media (max-width: 1080px) {
    html,
    body {
        height: auto;
        overflow: auto;
    }

    .app-shell {
        height: auto;
        min-height: 100dvh;
    }

    .workspace {
        grid-template-columns: 1fr;
        height: auto;
    }

    .cube-stage {
        min-height: 68vh;
        grid-template-rows: auto minmax(360px, 52vh) auto auto;
        border-right: 0;
        border-bottom: 1px solid var(--line);
        overflow: visible;
    }

    .setup-panel {
        height: auto;
        overflow: visible;
    }
}

@media (max-width: 720px) {
    .topbar {
        align-items: stretch;
        flex-direction: column;
    }

    .topbar-actions {
        justify-content: stretch;
        display: grid;
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

    .button {
        width: 100%;
        padding-inline: 10px;
    }

    .stage-toolbar {
        grid-template-columns: 1fr;
    }

    .stage-tools {
        display: grid;
        justify-content: stretch;
    }

    .canvas-mode-toggle {
        display: grid;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        width: 100%;
    }

    .mode-button {
        min-height: 36px;
    }

    .auto-orient-control {
        justify-content: center;
        min-height: 38px;
        width: 100%;
    }

    .playback-speed-control {
        grid-template-columns: auto minmax(88px, 1fr) 42px;
        min-height: 42px;
        width: 100%;
    }

    .view-controls {
        justify-content: stretch;
        display: grid;
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }

    .move-meter {
        width: 100%;
        text-align: left;
    }

    h1 {
        font-size: clamp(2.15rem, 12vw, 3.4rem);
    }

    #cubeCanvas {
        min-height: 360px;
    }

    body.canvas-paint-mode .canvas-paint-dock {
        display: grid;
        grid-template-columns: repeat(6, minmax(34px, 1fr));
        gap: 7px;
        align-items: center;
        margin-top: 8px;
        padding: 8px;
        border: 1px solid var(--line);
        border-radius: 8px;
        background: var(--glass-strong);
    }

    .canvas-paint-dock .palette-swatch {
        min-height: 38px;
    }

    .mobile-playback-controls {
        display: grid;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 8px;
        margin-top: 8px;
    }

    .mobile-playback-controls .button {
        min-height: 44px;
    }

    .cube-stage {
        grid-template-rows: auto minmax(360px, 52vh) auto auto;
        padding-inline: 14px;
    }

    .setup-panel {
        padding-inline: 12px;
    }

    .panel-section {
        padding: 13px;
    }

    .cube-net {
        width: min(100%, 350px);
    }

    .sticker {
        border-width: 1px;
        border-radius: 6px;
        font-size: 0.78rem;
    }

    .tutorial-drawer,
    .solve-guide-drawer {
        width: 100vw;
        border-left: 0;
    }

    .tutorial-header {
        min-height: 66px;
        padding-inline: 12px;
    }

    .tutorial-body,
    .solve-guide-body {
        grid-template-columns: 1fr;
        padding: 10px;
    }

    .solve-guide-step {
        grid-template-columns: 30px minmax(0, 1fr);
        gap: 9px;
        padding: 10px;
    }

    .guide-step-index {
        width: 30px;
        height: 30px;
    }

    .tutorial-preview,
    .tutorial-section {
        grid-column: 1;
    }

    .tutorial-preview {
        grid-row: auto;
        top: 0;
    }

    #tutorialCanvas {
        aspect-ratio: 16 / 10;
        min-height: 170px;
    }

    .tutorial-section-heading {
        display: grid;
    }

    .tutorial-section-heading p {
        max-width: none;
        text-align: left;
    }
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        scroll-behavior: auto !important;
        transition-duration: 0.01ms !important;
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
    }
}