/* Addition worked solution: scoped to the approved calculation preview. */
.physics-playground .addition-solution {
    --as-ink: #092444;
    --as-muted: #4c6480;
    --as-teal: #007675;
    margin: 16px 0;
    padding: 18px 26px 12px;
    border: 1px solid #cce8e5;
    border-radius: 10px;
    background: #fff;
    box-shadow: 0 3px 12px #084c4510;
    color: var(--as-ink);
    font-size: 16px;
    line-height: 1.45;
    scroll-margin-top: 110px;
}
.addition-solution__header { display: flex; justify-content: space-between; align-items: flex-start; gap: 16px; }
.addition-solution__eyebrow { display: block; color: #006c63; text-transform: uppercase; font-size: 12px; letter-spacing: .12em; font-weight: 600; }
.physics-playground .addition-solution h2 { margin: 0; color: var(--as-ink); font-size: 32px; line-height: 1.2; font-weight: 750; letter-spacing: -.025em; }
.physics-playground .addition-solution h3 { margin: 0 0 3px; color: var(--as-ink); font-size: 17px; line-height: 1.35; font-weight: 700; }
.physics-playground .addition-solution p { margin: 0 0 4px; color: var(--as-muted); }
.addition-solution__header > div > p { font-size: 18px; }
.physics-playground .addition-solution__header > button { border: 0; background: none; color: var(--as-teal); padding: 4px 0 12px 12px; font-size: 13px; font-weight: 600; cursor: pointer; }
.addition-solution__header > button span { margin-left: 6px; }
.addition-solution__given { display: flex; flex-wrap: wrap; gap: 10px 26px; align-items: center; margin: 9px 0 12px; padding: 11px 16px; border-radius: 8px; background: #eaf7f5; font-weight: 550; }
.addition-solution__given > span { display: inline-flex; align-items: center; gap: 14px; min-width: 0; overflow-wrap: anywhere; }
.addition-solution__given i { display: inline-block; width: 14px; height: 14px; border-radius: 50%; flex: 0 0 14px; box-shadow: inset -2px -2px 3px #0001; }
.addition-solution__given > strong { border-left: 1px solid #a3bfcb; padding-left: 25px; overflow-wrap: anywhere; }
.addition-solution__roadmap { display: flex; flex-wrap: wrap; gap: 12px 19px; list-style: none; margin: 0 0 10px; padding: 0; font-size: 14px; }
.addition-solution__roadmap li { display: flex; align-items: center; gap: 11px; }
.addition-solution__roadmap b { font-weight: inherit; }
.addition-solution__deeper .worked-check { padding: 9px 12px; margin-top: 10px; border-left: 3px solid #008c83; background: #eff9f6; }
.addition-solution__diagram .worked-diagram-note { margin: 8px 0 2px; font-size: 13px; }
.addition-solution__diagram-legend span { overflow-wrap: anywhere; max-width: 100%; }
.addition-solution__roadmap li:not(:last-child)::after { content: '→'; margin-left: 5px; color: #5b7491; font-size: 20px; }
.addition-solution__roadmap li > span { display: grid; place-items: center; width: 30px; height: 30px; border-radius: 50%; background: linear-gradient(135deg, #d3f1e8, #a8e0da); color: #074152; font-size: 16px; font-weight: 700; }
.addition-solution__body { display: grid; grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr); gap: 16px; align-items: start; }
.addition-solution__steps { list-style: none; margin: 0; padding: 0; }
.addition-solution__steps > li { display: grid; grid-template-columns: 44px minmax(0, 1fr); gap: 17px; padding: 13px 0 15px; border-top: 1px solid #dbe4ec; }
.addition-solution__steps > li:last-child { border-bottom: 1px solid #dbe4ec; padding-bottom: 26px; }
.addition-solution__number { display: grid; place-items: center; width: 40px; height: 40px; border-radius: 50%; background: linear-gradient(135deg, #009289, #005b63); color: #fff; font-size: 20px; font-weight: 650; }
.addition-solution__steps p { font-size: 15px; }
.addition-solution__resolve { display: flex; flex-wrap: wrap; gap: 5px 26px; }
.addition-solution__equation { margin: 3px 0; overflow-wrap: anywhere; }
.addition-solution math { font-family: 'STIX Two Math', 'Cambria Math', serif; font-size: 1.12em; max-width: 100%; }
.addition-solution__math-scroll { overflow-x: auto; padding: 5px 0; }
.addition-solution__input-details { margin-top: 5px; }
.addition-solution__input-details > summary { color: var(--as-muted); font-size: 13px; cursor: pointer; width: fit-content; }
.addition-solution__input-details > div { margin-top: 8px; }
.addition-solution__input-details article { border-left: 2px solid #bfdfda; padding: 0 0 0 10px; margin: 10px 0; font-size: 14px; }
.addition-solution__input-details article strong { display: block; margin-bottom: 4px; }
.addition-solution__diagram, .addition-solution__result { border-radius: 8px; background: #e7f7f4; padding: 12px 20px; }
.addition-solution__diagram > summary { display: flex; gap: 12px; align-items: center; color: #064454; font-weight: 700; cursor: pointer; list-style: none; }
.addition-solution summary::-webkit-details-marker { display: none; }
.addition-solution__diagram > summary::marker { content: ''; }
.addition-solution__chevron { margin-left: auto; }
.addition-solution__diagram[open] .addition-solution__chevron { transform: rotate(180deg); }
.addition-solution__mini { width: 44px; height: 32px; flex: 0 0 44px; display: none; }
.addition-solution__diagram > div > svg { display: block; width: 100%; height: auto; margin: 5px 0; }
.addition-solution__diagram-legend { display: flex; flex-wrap: wrap; gap: 5px 12px; font-size: 13px; }
.addition-solution__diagram-legend span { display: inline-flex; align-items: center; gap: 5px; }
.addition-solution__diagram-legend i { width: 10px; height: 10px; border-radius: 50%; }
.physics-playground .addition-solution__diagram > p { text-align: center; margin: 5px 0; font-size: 13px; }
.addition-solution__result { margin-top: 8px; }
.physics-playground .addition-solution__result h3 { color: #006a6b; font-size: 16px; }
.addition-solution__result strong { display: block; font-size: 21px; line-height: 1.25; }
.physics-playground .addition-solution__result p { margin-top: 4px; font-size: 15px; }
.physics-playground .addition-solution__deeper > h3 { font-size: 25px; letter-spacing: -.025em; margin: 6px 0; }
.addition-solution__deeper > details { border: 1px solid #dbe3eb; border-radius: 7px; margin-bottom: 3px; }
.addition-solution__deeper > details > summary { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 5px 15px; cursor: pointer; list-style: none; font-size: 16px; }
.addition-solution__deeper > details > summary > span { font-size: 22px; line-height: 1; }
.addition-solution__deeper > details[open] > summary > span { transform: rotate(45deg); }
.addition-solution__deeper > details > div { padding: 12px 16px 16px; border-top: 1px solid #e5ecee; }
.addition-solution__deeper h4 { margin: 13px 0 5px; font-size: 16px; color: #075b62; }
.addition-solution__deeper h4:first-child { margin-top: 0; }
.addition-solution__deeper ul { padding-left: 21px; margin: 8px 0; }
.addition-solution__deeper li { margin: 6px 0; }
.addition-solution__memory { display: flex; flex-wrap: wrap; align-items: center; gap: 14px 22px; margin-top: 13px; padding: 13px 16px; border-radius: 8px; background: #e7f7f4; }
.addition-solution__remember, .addition-solution__predict { display: flex; align-items: flex-start; gap: 13px; flex: 1 1 220px; }
.addition-solution__predict { padding-left: 24px; border-left: 1px solid #bad7de; }
.addition-solution__icon { width: 23px; height: 25px; flex: 0 0 23px; color: #006c6b; }
.physics-playground .addition-solution__memory h3 { font-size: 14px; color: #006b69; margin: 0 0 3px; }
.physics-playground .addition-solution__memory p { font-size: 13px; margin: 0; }
.physics-playground .addition-solution__memory > button { border: 0; border-radius: 7px; padding: 10px 20px; color: #fff; background: linear-gradient(135deg, #00847d, #006864); font-size: 14px; font-weight: 600; cursor: pointer; }
.addition-solution__prediction { flex-basis: 100%; border-top: 1px solid #bfdfda; padding-top: 12px; }
.addition-solution button:focus-visible, .addition-solution summary:focus-visible { outline: 3px solid #138d90; outline-offset: 3px; }
@media (max-width: 720px) {
    .physics-playground .addition-solution { padding: 14px 20px; margin: 12px 0; }
    .physics-playground .addition-solution h2 { font-size: 24px; }
    .addition-solution__header > div > p { font-size: 16px; }
    .physics-playground .addition-solution__header > button { font-size: 12px; white-space: nowrap; padding-left: 0; }
    .addition-solution__given { gap: 8px 20px; padding: 10px 15px; font-size: 15px; }
    .addition-solution__given > strong { padding-left: 15px; }
    .addition-solution__roadmap { gap: 8px 14px; font-size: 13px; }
    .addition-solution__roadmap li { gap: 8px; }
    .addition-solution__roadmap li:not(:last-child)::after { margin-left: 0; }
    .addition-solution__body { grid-template-columns: minmax(0, 1fr); gap: 12px; }
    .addition-solution__steps > li { gap: 15px; padding: 12px 0 16px; }
    .physics-playground .addition-solution h3 { font-size: 16px; }
    .addition-solution__steps > li:last-child { padding-bottom: 14px; }
    .addition-solution__mini { display: block; }
    .addition-solution__diagram { padding: 10px 16px; }
    .addition-solution__result { padding: 10px 16px; }
    .addition-solution__result strong { display: inline-block; margin-right: 18px; font-size: 20px; }
    .physics-playground .addition-solution__deeper > h3 { font-size: 24px; margin-top: 16px; }
    .addition-solution__deeper > details > summary { font-size: 15px; padding: 8px 14px; }
    .addition-solution__memory { display: grid; gap: 15px; padding: 17px; }
    .addition-solution__remember, .addition-solution__predict { min-width: 0; }
    .addition-solution__predict { border-left: 0; border-top: 1px solid #bad7de; padding: 14px 0 0; }
    .physics-playground .addition-solution__memory h3 { font-size: 16px; }
    .physics-playground .addition-solution__memory p { font-size: 14px; }
    .addition-solution__memory > button { justify-self: start; }
}

.physics-playground {
    --pp-page: #f5faf9;
    --pp-ink: #123f39;
    --pp-muted: #67837f;
    --pp-deep: #075c51;
    --pp-deeper: #064a42;
    --pp-dark: #063f39;
    --pp-green: #078878;
    --pp-mint: #72ead7;
    --pp-line: rgba(184, 255, 240, .34);
    --pp-white-line: rgba(255, 255, 255, .25);
    --pp-purple: #b55cff;
    --pp-yellow: #ffd44f;
    --pp-cyan: #45ead8;
    --pp-pink: #ff83a9;
    position: relative;
    left: 50%;
    width: min(1500px, calc(100vw - 48px));
    margin: -12px 0 3rem;
    transform: translateX(-50%);
    color: var(--pp-ink);
    font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.physics-playground *,
.physics-playground *::before,
.physics-playground *::after {
    box-sizing: border-box;
}

.physics-playground button,
.physics-playground select,
.physics-playground input {
    font: inherit;
}

.physics-playground button,
.physics-playground select {
    -webkit-tap-highlight-color: transparent;
}

.physics-playground [hidden] {
    display: none !important;
}

.physics-playground .sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.physics-playground__heading {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
    margin-bottom: 1rem;
    padding: 0 .9rem;
}

.physics-playground__heading-copy {
    display: flex;
    align-items: center;
    gap: .9rem;
}

.physics-playground__heading-icon {
    display: grid;
    flex: 0 0 52px;
    width: 52px;
    height: 52px;
    place-items: center;
    border-radius: 50%;
    background: #d7f5ed;
    color: #006f61;
}

.physics-playground__heading-icon svg {
    width: 32px;
    height: 32px;
    fill: none;
    stroke: currentColor;
    stroke-width: 2.2;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.physics-playground__heading h1 {
    margin: 0;
    color: #0b2e50;
    font-size: clamp(1.8rem, 3vw, 2.7rem);
    line-height: 1.05;
    letter-spacing: -.035em;
}

.physics-playground__heading p {
    margin: .25rem 0 0;
    color: #3f5c73;
    font-size: 1rem;
}

.physics-playground__back {
    display: inline-flex;
    align-items: center;
    gap: .55rem;
    color: #087d6d;
    font-size: .95rem;
    font-weight: 800;
    text-decoration: none;
}

.physics-playground__back span {
    font-size: 1.35rem;
    line-height: 1;
}

.physics-studio {
    overflow: hidden;
    border: 1px solid rgba(77, 224, 195, .62);
    border-radius: 24px;
    background:
        radial-gradient(circle at 82% 12%, rgba(82, 221, 194, .22), transparent 26%),
        linear-gradient(135deg, #087363 0%, #078878 48%, #087061 100%);
    box-shadow: 0 20px 46px rgba(7, 98, 85, .16);
    color: #fff;
}

.physics-studio__toolbar {
    display: flex;
    align-items: stretch;
    gap: .7rem;
    min-width: 0;
    padding: .85rem 1rem;
    border-bottom: 1px solid var(--pp-white-line);
    background: rgba(4, 86, 76, .3);
}

.physics-studio__labs,
.physics-studio__mode,
.physics-studio__dimension {
    display: flex;
    align-items: stretch;
    gap: .35rem;
}

.physics-studio__labs {
    flex: 1 1 330px;
    max-width: 420px;
}

.physics-studio__mode {
    flex: 0 0 auto;
}

.physics-studio__dimension {
    flex: 0 0 auto;
}

.physics-studio__toolbar button,
.physics-studio__labs a,
.physics-studio__operation select,
.physics-canvas__view button,
.physics-canvas__tools button,
.physics-canvas__zoom button {
    border: 1px solid var(--pp-white-line);
    background: rgba(4, 72, 64, .68);
    color: #fff;
    cursor: pointer;
}

.physics-studio__toolbar button:focus-visible,
.physics-studio__labs a:focus-visible,
.physics-studio__operation select:focus-visible,
.physics-canvas button:focus-visible,
.vector-inspector button:focus-visible,
.guided-experiments button:focus-visible {
    outline: 3px solid rgba(255, 212, 79, .9);
    outline-offset: 2px;
}

.physics-studio__labs button,
.physics-studio__labs a,
.physics-studio__mode button,
.physics-studio__dimension button,
.physics-studio__reset,
.physics-studio__operation select {
    min-height: 44px;
    border-radius: 10px;
    font-size: .84rem;
    font-weight: 800;
    white-space: nowrap;
}

.physics-studio__labs button,
.physics-studio__labs a {
    display: grid;
    place-items: center;
    flex: 1 1 0;
    padding: .45rem .85rem;
    text-align: center;
    text-decoration: none;
}

.physics-studio__labs small {
    display: block;
    margin-top: .08rem;
    color: rgba(255, 255, 255, .67);
    font-size: .58rem;
    font-weight: 700;
}

.physics-studio__toolbar button:disabled {
    cursor: default;
    opacity: .68;
}

.physics-studio__mode button,
.physics-studio__reset {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: .45rem;
    padding: .45rem .85rem;
}

.physics-studio__mode svg,
.physics-studio__reset svg {
    width: 18px;
    height: 18px;
    fill: none;
    stroke: currentColor;
    stroke-width: 1.9;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.physics-studio__dimension button {
    min-width: 52px;
    padding: .45rem .7rem;
}

.physics-studio__toolbar button.is-active,
.physics-studio__toolbar button[aria-pressed="true"],
.physics-canvas__view button.is-active,
.physics-canvas__tools button.is-active {
    border-color: rgba(115, 255, 225, .82);
    background: rgba(8, 93, 81, .88);
    box-shadow: inset 0 0 0 1px rgba(115, 255, 225, .16), 0 0 0 2px rgba(38, 218, 184, .09);
}

.physics-studio__operation {
    flex: 1 1 260px;
    min-width: 210px;
}

.physics-studio__operation select {
    width: 100%;
    padding: .45rem 2.2rem .45rem .85rem;
    color-scheme: dark;
}

.physics-studio__reset {
    flex: 0 0 auto;
    min-width: 92px;
}

.physics-studio__workspace {
    position: relative;
    display: grid;
    grid-template-columns: minmax(0, 1fr) 280px;
    min-height: 560px;
    gap: .75rem;
    margin: .75rem;
    padding: .75rem;
    overflow: hidden;
    border: 1px solid var(--pp-white-line);
    border-radius: 19px;
    background:
        radial-gradient(circle at 70% 24%, rgba(80, 215, 191, .12), transparent 30%),
        rgba(24, 151, 132, .34);
}

.physics-canvas {
    position: relative;
    min-width: 0;
    min-height: 536px;
    overflow: hidden;
    border: 0;
    border-radius: 13px;
    background: transparent;
}

.physics-canvas__stage {
    display: block;
    width: 100%;
    height: 100%;
    min-height: 536px;
    touch-action: none;
    user-select: none;
}

.physics-canvas__operation,
.physics-canvas__view,
.physics-canvas__tools,
.physics-canvas__tools-toggle,
.physics-canvas__zoom,
.physics-canvas__summary,
.physics-canvas__insight {
    position: absolute;
    z-index: 5;
}

.physics-canvas__tools-toggle,
.physics-canvas__insight-label--mobile {
    display: none;
}

.physics-canvas__fullscreen-controls,
.physics-fullscreen-drawer {
    display: none;
}

.physics-canvas__operation {
    top: 16px;
    left: 72px;
    padding: .48rem .72rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 999px;
    background: rgba(4, 72, 64, .72);
    color: #fff;
    font-size: .72rem;
    font-weight: 800;
}

.physics-canvas__view {
    top: 14px;
    right: 14px;
    display: flex;
    gap: .28rem;
}

.physics-canvas__view button {
    display: grid;
    min-width: 44px;
    height: 38px;
    padding: 0 .62rem;
    place-items: center;
    border-radius: 9px;
    font-size: .75rem;
    font-weight: 850;
}

.physics-canvas__view svg,
.physics-canvas__zoom svg,
.physics-canvas__summary svg {
    width: 18px;
    height: 18px;
    fill: none;
    stroke: currentColor;
    stroke-width: 1.9;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.physics-canvas__tools {
    top: 68px;
    left: 14px;
    display: grid;
    gap: .28rem;
    padding: .32rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 13px;
    background: rgba(4, 72, 64, .72);
}

.physics-canvas__tools button {
    display: grid;
    width: 40px;
    height: 40px;
    padding: 0;
    place-items: center;
    border-color: transparent;
    border-radius: 9px;
}

.physics-canvas__tools svg {
    width: 21px;
    height: 21px;
    fill: none;
    stroke: currentColor;
    stroke-width: 1.8;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.physics-canvas__zoom {
    bottom: 16px;
    left: 16px;
    display: flex;
    gap: .25rem;
    padding: .3rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 12px;
    background: rgba(4, 72, 64, .76);
}

.physics-canvas__zoom button {
    display: grid;
    width: 38px;
    height: 36px;
    padding: 0;
    place-items: center;
    border-color: transparent;
    border-radius: 8px;
    font-size: 1.35rem;
}

.physics-canvas__summary {
    right: 16px;
    bottom: 16px;
    display: flex;
    align-items: center;
    gap: .58rem;
    min-height: 42px;
    padding: .55rem .78rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 999px;
    background: rgba(4, 72, 64, .84);
    color: #fff;
    cursor: pointer;
    font-size: .72rem;
    font-weight: 800;
}

.physics-canvas__summary svg {
    color: #aaf5e7;
}

.physics-canvas__insight {
    bottom: 16px;
    left: 152px;
    display: flex;
    align-items: center;
    gap: .65rem;
    max-width: min(560px, calc(100% - 480px));
    min-height: 42px;
    padding: .48rem .7rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 999px;
    background: rgba(4, 72, 64, .76);
}

.physics-canvas__insight > span {
    display: grid;
    flex: 0 0 30px;
    width: 30px;
    height: 30px;
    place-items: center;
    border-radius: 50%;
    background: var(--pp-yellow);
    font-size: .9rem;
}

.physics-canvas__insight p {
    flex: 1 1 auto;
    margin: 0;
    overflow: hidden;
    font-size: .72rem;
    font-weight: 700;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.physics-canvas__insight button {
    flex: 0 0 auto;
    padding: 0 0 0 .65rem;
    border: 0;
    border-left: 1px solid var(--pp-white-line);
    background: transparent;
    color: #8df3e1;
    cursor: pointer;
    font-size: .7rem;
    font-weight: 850;
}

.physics-canvas__stage .pp-grid-line {
    stroke: rgba(190, 255, 242, .085);
    stroke-width: 1;
    vector-effect: non-scaling-stroke;
}

.physics-canvas__stage .pp-axis {
    stroke: rgba(255, 255, 255, .92);
    stroke-width: 2.2;
    vector-effect: non-scaling-stroke;
}

.physics-canvas__stage .pp-axis--depth {
    opacity: .72;
}

.physics-canvas__stage .pp-tick {
    stroke: rgba(255, 255, 255, .62);
    stroke-width: 1.2;
    vector-effect: non-scaling-stroke;
}

.physics-canvas__stage .pp-axis-label,
.physics-canvas__stage .pp-tick-label,
.physics-canvas__stage .pp-label {
    fill: #fff;
    font-family: Inter, system-ui, sans-serif;
    font-weight: 800;
    paint-order: stroke;
    stroke: rgba(5, 94, 82, .78);
    stroke-width: 3px;
    stroke-linejoin: round;
}

.physics-canvas__stage .pp-axis-label {
    font-size: 18px;
}

.physics-canvas__stage .pp-tick-label {
    font-size: 11px;
    font-weight: 600;
    opacity: .78;
}

.physics-canvas__stage .pp-vector,
.physics-canvas__stage .pp-result,
.physics-canvas__stage .pp-component,
.physics-canvas__stage .pp-projection-path {
    fill: none;
    stroke-linecap: round;
    stroke-linejoin: round;
    vector-effect: non-scaling-stroke;
}

.physics-canvas__stage .pp-vector {
    stroke-width: 5;
}

.physics-canvas__stage .pp-vector--a { stroke: var(--pp-purple); }
.physics-canvas__stage .pp-vector--b { stroke: #ffb34d; }

.physics-canvas__stage .pp-result {
    stroke: #fff;
    stroke-width: 4;
    stroke-dasharray: 9 7;
}

.physics-canvas__stage .pp-component {
    stroke-width: 3;
    stroke-dasharray: 8 7;
}

.physics-canvas__stage .pp-component--x { stroke: var(--pp-cyan); }
.physics-canvas__stage .pp-component--y { stroke: var(--pp-pink); }
.physics-canvas__stage .pp-component--z { stroke: #9bb8ff; }
.physics-canvas__stage .pp-projection-path { stroke: #8ef4e1; stroke-width: 4; }

.physics-canvas__stage .pp-angle {
    fill: none;
    stroke: var(--pp-yellow);
    stroke-width: 4;
    stroke-linecap: round;
    vector-effect: non-scaling-stroke;
}

.physics-canvas__stage .pp-label {
    font-size: 17px;
}

.physics-canvas__stage .pp-label--a { fill: #e1b8ff; }
.physics-canvas__stage .pp-label--b { fill: #ffd199; }
.physics-canvas__stage .pp-label--x { fill: var(--pp-cyan); }
.physics-canvas__stage .pp-label--y { fill: #ffacc4; }
.physics-canvas__stage .pp-label--z { fill: #c5d3ff; }
.physics-canvas__stage .pp-label--theta { fill: var(--pp-yellow); }
.physics-canvas__stage .pp-label--result { fill: #fff; }
.physics-canvas__stage .pp-label[data-label-id] { cursor: grab; pointer-events: auto; touch-action: none; }
.physics-canvas__stage .pp-label[data-label-id]:active { cursor: grabbing; }
.physics-canvas__stage .pp-label-leader {
    stroke: rgba(255, 255, 255, .58);
    stroke-width: 1;
    stroke-dasharray: 3 3;
    vector-effect: non-scaling-stroke;
    pointer-events: none;
}

/* Full-screen focus mode: controls and calculations share one contextual drawer. */
.physics-canvas:fullscreen {
    width: 100vw;
    height: 100vh;
    min-height: 100vh;
    border-radius: 0;
    background: #020807;
}

.physics-canvas:fullscreen .physics-canvas__stage {
    width: 100%;
    height: 100%;
    min-height: 100%;
    transition: width .22s ease;
}

.physics-canvas:fullscreen.is-fullscreen-drawer-open .physics-canvas__stage {
    width: calc(100% - min(390px, 38vw));
}

.physics-canvas:fullscreen .physics-canvas__fullscreen-controls {
    position: absolute;
    z-index: 8;
    top: 14px;
    right: 158px;
    display: inline-flex;
    align-items: center;
    gap: .4rem;
    min-height: 38px;
    padding: 0 .75rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 9px;
    background: rgba(4, 72, 64, .8);
    color: #fff;
    cursor: pointer;
    font-size: .75rem;
    font-weight: 800;
}

.physics-canvas:fullscreen .physics-canvas__fullscreen-controls[aria-expanded="true"] {
    border-color: rgba(115, 255, 225, .82);
    background: rgba(8, 93, 81, .94);
}

.physics-canvas__fullscreen-controls svg {
    width: 17px;
    height: 17px;
    fill: none;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
}

.physics-canvas:fullscreen .physics-fullscreen-drawer {
    position: absolute;
    z-index: 12;
    top: 62px;
    right: 12px;
    bottom: 62px;
    display: flex;
    width: min(378px, calc(100vw - 24px));
    overflow: hidden;
    flex-direction: column;
    border: 1px solid rgba(143, 235, 218, .34);
    border-radius: 16px;
    background: rgba(3, 38, 35, .97);
    box-shadow: 0 20px 60px rgba(0, 0, 0, .48);
    color: #fff;
}

.physics-canvas:fullscreen .physics-fullscreen-drawer[hidden] {
    display: none;
}

.physics-fullscreen-drawer > header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    padding: .85rem 1rem;
    border-bottom: 1px solid var(--pp-white-line);
}

.physics-fullscreen-drawer > header h2 {
    margin: 0;
    color: #fff;
    font-size: 1rem;
}

.physics-fullscreen-drawer > header button {
    display: grid;
    width: 32px;
    height: 32px;
    padding: 0;
    place-items: center;
    border: 1px solid var(--pp-white-line);
    border-radius: 8px;
    background: rgba(8, 93, 81, .86);
    color: #fff;
    cursor: pointer;
    font-size: 1.35rem;
    line-height: 1;
}

.physics-fullscreen-drawer__body {
    min-height: 0;
    padding: .75rem;
    overflow: auto;
    overscroll-behavior: contain;
}

.physics-fullscreen-drawer .vector-inspector,
.physics-fullscreen-drawer .addition-solution {
    width: 100%;
    margin: 0;
}

.physics-fullscreen-drawer .physics-studio__operation {
    display: block;
    width: 100%;
    min-width: 0;
    margin-bottom: .55rem;
}

.physics-fullscreen-drawer .physics-studio__operation select {
    width: 100%;
}

.physics-fullscreen-drawer .physics-studio__dimension {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: .35rem;
    margin-bottom: .65rem;
}

.physics-fullscreen-drawer .physics-studio__dimension button {
    width: 100%;
}

.physics-fullscreen-drawer .vector-inspector {
    background: rgba(4, 72, 64, .72);
}

.physics-fullscreen-drawer .addition-solution {
    padding: 1rem;
    border: 0;
    border-radius: 12px;
}

.physics-fullscreen-drawer .addition-solution__body {
    grid-template-columns: minmax(0, 1fr);
}

.physics-fullscreen-drawer .addition-solution__roadmap {
    gap: 7px 10px;
    font-size: 12px;
}

.physics-fullscreen-drawer .addition-solution__roadmap li {
    gap: 6px;
}

.physics-fullscreen-drawer .addition-solution__roadmap li:not(:last-child)::after {
    margin-left: 0;
}

.physics-fullscreen-drawer .addition-solution__memory {
    display: grid;
}

.physics-fullscreen-drawer .addition-solution__predict {
    padding: 13px 0 0;
    border-top: 1px solid #bad7de;
    border-left: 0;
}

/* Full-screen label hierarchy: result, vectors, components, then scale markings. */
.physics-canvas:fullscreen .physics-canvas__stage .pp-axis-label {
    font-size: 13px;
    stroke-width: 2px;
}

.physics-canvas:fullscreen .physics-canvas__stage .pp-tick-label {
    font-size: 9px;
    stroke-width: 1.8px;
}

.physics-canvas:fullscreen .physics-canvas__stage .pp-label {
    font-size: 14px;
    stroke-width: 2px;
}

.physics-canvas:fullscreen .physics-canvas__stage .pp-label--a,
.physics-canvas:fullscreen .physics-canvas__stage .pp-label--b {
    font-size: 15px;
}

.physics-canvas:fullscreen .physics-canvas__stage .pp-label--x,
.physics-canvas:fullscreen .physics-canvas__stage .pp-label--y,
.physics-canvas:fullscreen .physics-canvas__stage .pp-label--z,
.physics-canvas:fullscreen .physics-canvas__stage .pp-label--theta {
    font-size: 12px;
    font-weight: 750;
}

.physics-canvas:fullscreen .physics-canvas__stage .pp-label--result {
    font-size: 16px;
    stroke-width: 2.4px;
}

@media (max-width: 720px) {
    .physics-canvas:fullscreen {
        height: 100vh;
        padding: 0;
    }

    .physics-canvas:fullscreen .physics-canvas__stage,
    .physics-canvas:fullscreen.is-fullscreen-drawer-open .physics-canvas__stage {
        width: 100%;
        height: 100%;
    }

    .physics-canvas:fullscreen .physics-canvas__fullscreen-controls {
        top: 7px;
        right: 124px;
        min-height: 34px;
        padding: 0 .55rem;
        font-size: .68rem;
    }

    .physics-canvas:fullscreen .physics-fullscreen-drawer {
        top: auto;
        right: 8px;
        bottom: 8px;
        left: 8px;
        width: auto;
        max-height: min(68vh, 620px);
        border-radius: 15px;
    }

    .physics-canvas:fullscreen .physics-fullscreen-drawer__body {
        padding: .55rem;
    }

    .physics-fullscreen-drawer .addition-solution__header h2 {
        font-size: 1.45rem;
    }
}

.physics-canvas__stage .pp-handle-visual {
    fill: rgba(255, 255, 255, .3);
    stroke-width: 5;
    vector-effect: non-scaling-stroke;
}

.physics-canvas__stage .pp-handle-visual--a {
    fill: rgba(255, 255, 255, .18);
    stroke: rgba(181, 92, 255, .52);
    stroke-width: 3;
}
.physics-canvas__stage .pp-handle-visual--b { stroke: rgba(255, 179, 77, .72); }

.physics-canvas__stage .pp-handle-hit {
    fill: transparent;
    cursor: grab;
    touch-action: none;
}

.physics-canvas__stage .pp-handle-hit:active { cursor: grabbing; }

.physics-canvas__stage .pp-cross-symbol {
    fill: rgba(4, 72, 64, .82);
    stroke: #fff;
    stroke-width: 2;
}

.physics-canvas__stage .pp-cross-dot {
    fill: #fff;
}

.vector-inspector,
.calculation-panel {
    align-self: start;
    min-width: 0;
    padding: 1rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 18px;
    background: rgba(4, 72, 64, .72);
    color: #fff;
}

.physics-studio__sidebar {
    display: grid;
    min-width: 0;
    align-content: start;
    gap: .75rem;
}

.vector-inspector__header,
.calculation-panel__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: .75rem;
}

.vector-inspector__header > div {
    display: flex;
    align-items: center;
    gap: .6rem;
}

.vector-inspector__swatch {
    display: block;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: var(--pp-purple);
}

.vector-inspector__header h2,
.calculation-panel__header h2 {
    margin: 0;
    color: #fff;
    font-size: 1.16rem;
    line-height: 1.1;
}

.vector-inspector__header > button,
.calculation-panel__header > button {
    display: grid;
    width: 34px;
    height: 34px;
    padding: 0;
    place-items: center;
    border: 0;
    border-radius: 8px;
    background: transparent;
    color: #fff;
    cursor: pointer;
    font-size: 1.25rem;
}

.vector-inspector__body {
    margin-top: 1rem;
}

.vector-inspector__tabs {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: .35rem;
    margin-bottom: .95rem;
    padding: .25rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 10px;
}

.vector-inspector__tabs button {
    min-height: 34px;
    border: 0;
    border-radius: 7px;
    background: transparent;
    color: rgba(255, 255, 255, .7);
    cursor: pointer;
    font-size: .7rem;
    font-weight: 800;
}

.vector-inspector__tabs button.is-active {
    background: rgba(38, 202, 173, .28);
    color: #fff;
}

.vector-control {
    --range-accent: var(--pp-purple);
    display: block;
    margin-top: 1rem;
}

.vector-control:first-of-type { margin-top: 0; }
.vector-control--direction { --range-accent: var(--pp-yellow); }
.vector-control--elevation { --range-accent: #9bb8ff; }

.vector-control > span,
.vector-inspector__advanced > label > span {
    display: grid;
    grid-template-columns: auto auto 1fr;
    align-items: center;
    gap: .28rem;
    margin-bottom: .55rem;
    font-size: .78rem;
    font-weight: 750;
}

.vector-control i {
    font-family: Georgia, serif;
    font-style: italic;
}

.vector-control__entry,
.vector-inspector__advanced output {
    justify-self: end;
    font-size: .86rem;
    font-weight: 850;
}

.vector-control__entry {
    width: 4.8rem;
    min-height: 30px;
    padding: .22rem .4rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 7px;
    outline: 0;
    background: rgba(3, 62, 55, .6);
    color: #fff;
    font-family: Inter, system-ui, sans-serif;
    text-align: right;
}

.vector-control__entry:focus {
    border-color: rgba(255, 255, 255, .8);
    box-shadow: 0 0 0 2px rgba(255, 255, 255, .12);
}

.vector-control input[type="range"],
.vector-inspector__advanced input[type="range"] {
    width: 100%;
    height: 7px;
    margin: 0;
    border-radius: 999px;
    outline: 0;
    appearance: none;
    background: linear-gradient(
        to right,
        var(--range-accent) 0,
        var(--range-accent) var(--range-progress, 50%),
        rgba(2, 60, 53, .82) var(--range-progress, 50%),
        rgba(2, 60, 53, .82) 100%
    );
    cursor: pointer;
}

.vector-control input[type="range"]::-webkit-slider-thumb,
.vector-inspector__advanced input[type="range"]::-webkit-slider-thumb {
    width: 19px;
    height: 19px;
    border: 3px solid var(--range-accent);
    border-radius: 50%;
    appearance: none;
    background: #fff;
    box-shadow: 0 2px 8px rgba(0, 0, 0, .17);
}

.vector-control input[type="range"]::-moz-range-thumb,
.vector-inspector__advanced input[type="range"]::-moz-range-thumb {
    width: 14px;
    height: 14px;
    border: 3px solid var(--range-accent);
    border-radius: 50%;
    background: #fff;
    box-shadow: 0 2px 8px rgba(0, 0, 0, .17);
}

.vector-control > small {
    display: flex;
    justify-content: space-between;
    margin-top: .35rem;
    color: rgba(255, 255, 255, .72);
    font-size: .65rem;
}

.vector-inspector__components {
    margin-top: 1rem;
    padding-top: .9rem;
    border-top: 1px solid var(--pp-white-line);
}

.vector-inspector__components > span {
    display: block;
    margin-bottom: .55rem;
    font-size: .72rem;
    font-weight: 800;
}

.vector-inspector__components > span small {
    color: #9cf2e2;
    font-weight: 600;
}

.vector-inspector__components > div {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: .5rem;
}

.vector-inspector__components > div.is-3d {
    grid-template-columns: repeat(3, minmax(0, 1fr));
}

.vector-inspector__components label {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: .5rem;
    padding: .5rem .65rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 9px;
    color: rgba(255, 255, 255, .86);
    font-family: Georgia, serif;
    font-size: .75rem;
    font-style: italic;
}

.vector-inspector__components label > span {
    display: inline-flex;
    align-items: baseline;
    white-space: nowrap;
}

.vector-inspector__components input {
    min-width: 0;
    width: 4rem;
    padding: 0;
    border: 0;
    outline: 0;
    background: transparent;
    color: #fff;
    font-family: Inter, system-ui, sans-serif;
    font-size: .86rem;
    font-style: normal;
    font-weight: 850;
    text-align: right;
}

.vector-inspector__advanced {
    display: grid;
    gap: .65rem;
    margin-top: .9rem;
    padding: .8rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 10px;
    background: rgba(5, 81, 72, .55);
}

.vector-inspector__advanced > label {
    display: flex;
    align-items: center;
    gap: .5rem;
    color: rgba(255, 255, 255, .85);
    font-size: .7rem;
    font-weight: 700;
}

.vector-inspector__advanced > label:has(input[type="range"]) {
    --range-accent: #fff;
    display: block;
}

.vector-inspector__advanced input[type="checkbox"] {
    accent-color: var(--pp-mint);
}

.vector-inspector__more {
    display: grid;
    grid-template-columns: auto 1fr auto;
    align-items: center;
    gap: .55rem;
    width: 100%;
    min-height: 44px;
    margin-top: 1rem;
    padding: .55rem .65rem;
    border: 1px solid var(--pp-white-line);
    border-radius: 10px;
    background: rgba(4, 72, 64, .66);
    color: #fff;
    cursor: pointer;
    text-align: left;
    font-size: .75rem;
    font-weight: 800;
}

.vector-inspector__more svg {
    width: 19px;
    height: 19px;
    fill: none;
    stroke: currentColor;
    stroke-width: 1.8;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.calculation-panel {
    padding: .9rem 1rem;
}

.calculation-panel__header span,
.calculation-panel__formula span,
.calculation-panel__working span,
.calculation-panel__meaning span {
    display: block;
    margin-bottom: .35rem;
    color: #90efdf;
    font-size: .62rem;
    font-weight: 850;
    letter-spacing: .08em;
    text-transform: uppercase;
}

.calculation-panel__values {
    display: grid;
    grid-template-columns: 1fr;
    gap: .28rem;
    margin-top: .8rem;
}

.calculation-panel__values span {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: .75rem;
    padding: .08rem 0;
    color: #9cefe1;
    font-size: .7rem;
}

.calculation-panel__values small {
    color: #baf5eb;
    font-size: .78rem;
    font-weight: 750;
}

.calculation-panel__values strong {
    color: #fff;
    font-size: .86rem;
}

.calculation-panel__formula,
.calculation-panel__working,
.calculation-panel__meaning {
    margin-top: .65rem;
    padding-top: .65rem;
    border-top: 1px solid var(--pp-white-line);
}

.calculation-panel__formula strong {
    display: block;
    color: #fff;
    font-family: Georgia, serif;
    font-size: .82rem;
    line-height: 1.45;
}

.calculation-panel__working p,
.calculation-panel__meaning p {
    margin: 0;
    color: rgba(255, 255, 255, .88);
    font-size: .75rem;
    line-height: 1.55;
}

.calculation-panel__formula strong > span,
.calculation-panel__working p > span {
    display: block;
}

.guided-experiments {
    margin-top: .9rem;
    padding: 1rem 1.15rem;
    border: 1px solid #d8e7e4;
    border-radius: 18px;
    background: #fff;
    box-shadow: 0 12px 30px rgba(22, 76, 67, .06);
}

.guided-experiments header,
.guided-experiments header > div,
.guided-experiments__progress {
    display: flex;
    align-items: center;
}

.guided-experiments header {
    justify-content: space-between;
    gap: 1rem;
}

.guided-experiments header > div:first-child {
    gap: .7rem;
}

.guided-experiments__icon {
    display: grid;
    flex: 0 0 42px;
    width: 42px;
    height: 42px;
    place-items: center;
    border-radius: 50%;
    background: #dcf7f1;
    color: #087d6d;
    font-size: 1.55rem;
    font-weight: 850;
}

.guided-experiments h2 {
    margin: 0;
    color: #0b2e50;
    font-size: 1rem;
}

.guided-experiments header p {
    margin: .12rem 0 0;
    color: #647d91;
    font-size: .72rem;
}

.guided-experiments__progress {
    gap: .55rem;
    min-width: 190px;
}

.guided-experiments__progress strong {
    color: #087d6d;
    font-size: .72rem;
}

.guided-experiments__progress > span {
    flex: 1 1 auto;
    height: 8px;
    overflow: hidden;
    border-radius: 999px;
    background: #dce7ec;
}

.guided-experiments__progress i {
    display: block;
    width: 0;
    height: 100%;
    border-radius: inherit;
    background: #0ab794;
    transition: width .25s ease;
}

.guided-experiments__cards {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: .7rem;
    margin-top: .8rem;
}

.guided-experiments__cards button {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr) auto;
    align-items: center;
    gap: .65rem;
    min-height: 76px;
    padding: .65rem;
    border: 1px solid #d8e5eb;
    border-radius: 12px;
    background: #fbfdfd;
    color: #0b2e50;
    cursor: pointer;
    text-align: left;
}

.guided-experiments__cards button > span {
    display: grid;
    width: 38px;
    height: 38px;
    place-items: center;
    border-radius: 50%;
    background: #ffb347;
    color: #173b35;
    font-weight: 850;
}

.guided-experiments__cards button:nth-child(2) > span { background: #3aa8ff; color: #fff; }
.guided-experiments__cards button:nth-child(3) > span { background: #35df88; }

.guided-experiments__cards strong {
    font-size: .76rem;
}

.guided-experiments__cards small {
    display: block;
    margin-top: .2rem;
    color: #6b8193;
    font-size: .64rem;
    font-weight: 500;
    line-height: 1.35;
}

.guided-experiments__cards i {
    color: #087d6d;
    font-size: 1.25rem;
    font-style: normal;
}

.guided-experiments__cards button.is-active {
    border-color: #0ab794;
    box-shadow: 0 0 0 2px rgba(10, 183, 148, .1);
}

.guided-experiments__cards button.is-complete {
    background: #edf9f5;
}

.guided-experiments__cards button.is-complete > span::after {
    content: '✓';
}

.guided-experiments__cards button.is-complete > span {
    color: transparent;
    position: relative;
}

.guided-experiments__cards button.is-complete > span::after {
    position: absolute;
    color: #075c51;
}

.guided-experiments__note {
    margin: .7rem 0 0;
    color: #748b86;
    font-size: .65rem;
    text-align: center;
}

.guided-experiments__feedback {
    margin-top: .75rem;
    padding: .7rem .85rem;
    border: 1px solid #8bddca;
    border-radius: 10px;
    background: #eaf9f5;
    color: #075c51;
    font-size: .78rem;
    font-weight: 750;
}

@media (max-width: 1120px) {
    .physics-playground { width: min(1180px, calc(100vw - 36px)); }
    .physics-studio__toolbar { overflow-x: auto; }
    .physics-studio__toolbar > * { flex-shrink: 0; }
    .physics-studio__labs { flex-basis: 330px; }
    .physics-studio__operation { flex-basis: 240px; }
    .physics-studio__workspace { grid-template-columns: minmax(0, 1fr) 250px; }
    .physics-canvas__insight { max-width: calc(100% - 430px); }
}

@media (max-width: 900px) {
    .physics-studio__workspace { grid-template-columns: 1fr; }
    .physics-studio__sidebar { grid-column: 1; grid-row: auto; }
    .vector-inspector,
    .calculation-panel { grid-column: 1; grid-row: auto; }
    .physics-canvas__insight { max-width: calc(100% - 445px); }
    .guided-experiments__cards { overflow-x: auto; grid-template-columns: repeat(3, minmax(240px, 1fr)); }
}

@media (max-width: 720px) {
    .physics-playground {
        width: calc(100vw - 20px);
        margin-top: -8px;
        margin-bottom: 2rem;
    }

    .physics-playground__heading {
        align-items: flex-start;
        flex-direction: column;
        gap: .65rem;
        padding: 0 .25rem;
    }

    .physics-playground__heading-copy { gap: .65rem; }
    .physics-playground__heading-icon { flex-basis: 42px; width: 42px; height: 42px; }
    .physics-playground__heading-icon svg { width: 27px; height: 27px; }
    .physics-playground__heading h1 { font-size: 1.8rem; }
    .physics-playground__heading p { font-size: .88rem; }
    .physics-playground__back { font-size: .82rem; }

    .physics-studio { border-radius: 18px; }
    .physics-studio__toolbar { gap: .45rem; padding: .65rem; scrollbar-width: none; }
    .physics-studio__toolbar::-webkit-scrollbar { display: none; }
    .physics-studio__labs { flex: 0 0 auto; }
    .physics-studio__labs button:not(.is-active) { display: none; }
    .physics-studio__labs button { min-width: 86px; }
    .physics-studio__mode button[data-mode="guided"] { display: none; }
    .physics-studio__operation { flex: 0 0 210px; min-width: 210px; }
    .physics-studio__toolbar button,
    .physics-studio__operation select { min-height: 42px; font-size: .75rem; }

    .physics-studio__workspace { min-height: 0; gap: .55rem; margin: .6rem; padding: .55rem; border-radius: 14px; }
    .physics-canvas {
        height: 366px;
        min-height: 0;
        padding-top: 48px;
        padding-bottom: 58px;
        border-radius: 14px;
        transition: height .2s ease, padding-top .2s ease;
    }
    .physics-canvas.is-mobile-tools-open {
        height: 454px;
        padding-top: 136px;
    }
    .physics-canvas__stage { min-height: 0; height: 260px; }
    .physics-canvas__stage .pp-vector { stroke-width: 4; }
    .physics-canvas__stage .pp-component { stroke-width: 2.25; }
    .physics-canvas__stage .pp-angle { stroke-width: 3; }
    .physics-canvas__operation { display: none; }
    .physics-canvas__tools-toggle {
        top: 7px;
        left: 8px;
        display: inline-flex;
        align-items: center;
        gap: .38rem;
        min-width: 72px;
        height: 34px;
        padding: 0 .6rem;
        border: 1px solid var(--pp-white-line);
        border-radius: 9px;
        background: rgba(4, 72, 64, .76);
        color: #fff;
        cursor: pointer;
        font-size: .7rem;
        font-weight: 850;
    }
    .physics-canvas__tools-toggle svg {
        width: 17px;
        height: 17px;
        fill: none;
        stroke: currentColor;
        stroke-width: 2;
        stroke-linecap: round;
    }
    .physics-canvas__tools {
        top: 48px;
        right: 9px;
        left: 9px;
        display: none;
        grid-template-columns: repeat(6, minmax(0, 1fr));
        gap: .25rem;
        padding: .28rem;
    }
    .physics-canvas.is-mobile-tools-open .physics-canvas__tools { display: grid; }
    .physics-canvas__tools button { width: 100%; height: 34px; }
    .physics-canvas__tools svg { width: 18px; height: 18px; }
    .physics-canvas__view { top: 7px; right: 8px; }
    .physics-canvas__view button { min-width: 34px; height: 34px; padding: 0 .45rem; font-size: .66rem; }
    .physics-canvas__zoom {
        top: 94px;
        bottom: auto;
        left: 9px;
        display: none;
        padding: .25rem;
    }
    .physics-canvas.is-mobile-tools-open .physics-canvas__zoom { display: flex; }
    .physics-canvas__zoom button { width: 32px; height: 30px; }
    .physics-canvas__summary { right: 10px; bottom: 74px; min-height: 38px; font-size: .66rem; }

    .physics-canvas__insight {
        right: 8px;
        bottom: 7px;
        left: 8px;
        max-width: none;
        min-height: 44px;
        gap: .42rem;
        padding: .35rem .48rem;
        border-radius: 12px;
    }

    .physics-canvas__insight > span {
        flex-basis: 27px;
        width: 27px;
        height: 27px;
        font-size: .78rem;
    }
    .physics-canvas__insight p {
        font-size: .66rem;
        line-height: 1.25;
        white-space: nowrap;
    }
    .physics-canvas__insight button {
        padding-left: .45rem;
        font-size: .66rem;
        white-space: nowrap;
    }
    .physics-canvas__insight-label--desktop { display: none; }
    .physics-canvas__insight-label--mobile { display: inline; }

    .vector-inspector,
    .calculation-panel { border-radius: 14px; }
    .vector-inspector { padding: .72rem; }
    .vector-inspector__header > div { gap: .48rem; }
    .vector-inspector__swatch { width: 24px; height: 24px; }
    .vector-inspector__header h2 { font-size: 1.02rem; }
    .vector-inspector__header > button { width: 30px; height: 30px; }
    .vector-inspector__body { margin-top: .58rem; }
    .vector-inspector__tabs { margin-bottom: .58rem; }
    .vector-control { margin-top: .58rem; }
    .vector-control > span { margin-bottom: .3rem; }
    .vector-control > small { margin-top: .2rem; }
    .vector-control input[type="range"] { height: 6px; }
    .vector-control input[type="range"]::-webkit-slider-thumb { width: 17px; height: 17px; }
    .vector-control input[type="range"]::-moz-range-thumb { width: 12px; height: 12px; }
    .vector-inspector__components { margin-top: .58rem; padding-top: .55rem; }
    .vector-inspector__components > span { margin-bottom: .35rem; }
    .vector-inspector__components label { padding: .4rem .55rem; }
    .vector-inspector__more { min-height: 38px; margin-top: .58rem; padding: .42rem .55rem; }
    .vector-inspector__components > div.is-3d { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .calculation-panel { max-height: none; }

    .guided-experiments { padding: .85rem; border-radius: 15px; }
    .guided-experiments header { align-items: flex-start; flex-direction: column; }
    .guided-experiments__progress { width: 100%; }
    .guided-experiments__cards { grid-template-columns: repeat(3, 250px); }
}

@media (max-width: 430px) {
    .physics-studio__dimension { display: none; }
    .physics-canvas__stage .pp-vector { stroke-width: 3.5; }
    .physics-canvas__stage .pp-component { stroke-width: 2; }
    .physics-canvas__stage .pp-angle { stroke-width: 2.5; }
    .physics-canvas__view button[data-canvas-dimension="3d"] { display: grid; }
    .physics-canvas__summary span:nth-child(2) { max-width: 145px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
    .vector-inspector__components > div.is-3d { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (prefers-reduced-motion: reduce) {
    .physics-playground *,
    .physics-playground *::before,
    .physics-playground *::after {
        scroll-behavior: auto !important;
        transition: none !important;
    }
}

/* Coordinate entry and signed direction, shared by desktop and mobile. */
.vector-control__direction-entry { justify-self: end; display: grid; justify-items: end; gap: .15rem; }
.vector-control__direction-entry small { color: #90efbd; font-size: .7rem; font-weight: 600; }
.vector-coordinates { margin-top: .6rem; border: 1px solid var(--pp-white-line); border-radius: 9px; padding: .5rem .6rem; }
.vector-coordinates summary { cursor: pointer; font-size: .78rem; font-weight: 750; }
.vector-coordinates p { font-size: .75rem; margin: .5rem 0; }
.vector-coordinates fieldset { min-width: 0; padding: 0; border: 0; margin: .55rem 0; }
.vector-coordinates legend { font-size: .75rem; margin-bottom: .3rem; }
.vector-coordinates__fields { display: flex; gap: .4rem; }
.vector-coordinates__fields label { flex: 1; min-width: 0; font-size: .75rem; }
.vector-coordinates input { display: block; width: 100%; min-width: 0; padding: .4rem; border: 1px solid var(--pp-white-line); border-radius: 6px; background: #075c51; color: white; }
.vector-coordinates button { width: 100%; padding: .55rem; border: 1px solid var(--pp-white-line); border-radius: 7px; background: #075c51; color: white; cursor: pointer; }
.physics-canvas__stage .pp-angle-reference { stroke: #c3f7e7; stroke-width: 1; stroke-dasharray: 4 4; opacity: .6; vector-effect: non-scaling-stroke; }

/* Compact controls for any number of vectors. */
.vector-picker { display: flex; gap: .35rem; margin-bottom: .55rem; }
.vector-picker select { flex: 1; min-width: 0; }
.vector-picker select, .vector-operands select, .vector-picker button, [data-vector-name] {
    border: 1px solid var(--pp-white-line); border-radius: 7px; background: #075c51; color: white; padding: .35rem; font-size: .75rem;
}
.vector-picker button { width: 34px; min-height: 32px; cursor: pointer; font-size: 1.1rem; }
.vector-operands { display: flex; gap: .4rem; margin-bottom: .6rem; }
.vector-operands label { flex: 1; min-width: 0; font-size: .7rem; }
.vector-operands select { display: block; width: 100%; margin-top: .2rem; }
.vector-sum { margin-bottom: .5rem; font-size: .72rem; }
.vector-sum summary { cursor: pointer; }
.vector-sum > div { display: flex; flex-wrap: wrap; gap: .5rem; padding-top: .4rem; }
.vector-sum label { display: flex; align-items: center; gap: .2rem; }
.vector-subtraction summary { color: #fff; font-weight: 750; }
.vector-subtraction input { accent-color: var(--pp-yellow); }
.vector-scalar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: .6rem;
    margin: .45rem 0 .15rem;
    color: rgba(255, 255, 255, .9);
    font-size: .72rem;
    font-weight: 750;
}
.vector-scalar i { font-family: Georgia, serif; font-style: italic; }
.vector-label-placement { justify-content: space-between; }
.vector-label-placement select,
.vector-label-reset {
    min-width: 0;
    border: 1px solid var(--pp-white-line);
    border-radius: 7px;
    background: #075c51;
    color: #fff;
    font-size: .68rem;
}
.vector-label-placement select { max-width: 7rem; padding: .28rem; }
.vector-label-reset { width: 100%; padding: .38rem .5rem; cursor: pointer; }
.vector-coordinates { border: 0; padding: 0; margin-top: .35rem; }
.vector-coordinates summary { display: inline-flex; align-items: center; gap: .35rem; list-style: none; color: #9cf2e2; font-size: .6rem; font-weight: 600; cursor: pointer; padding: .25rem 0; }
.vector-coordinates summary::-webkit-details-marker { display: none; }
.vector-coordinates summary::after { content: ''; width: 5px; height: 5px; border-right: 1px solid currentColor; border-bottom: 1px solid currentColor; transform: rotate(45deg); margin-top: -3px; }
.vector-coordinates[open] summary::after { transform: rotate(225deg); margin-top: 3px; }
.vector-inspector .vector-inspector__more { min-height: 32px; padding: .3rem .5rem; margin-top: .5rem; font-size: .68rem; border-radius: 8px; }
.vector-inspector__more svg { width: 15px; height: 15px; }
[data-vector-name] { width: 100%; min-width: 0; }

/* Compact number entries, removal and expanded operation formulas. */
.vector-inspector .vector-control__entry { width: 4.9rem; min-height: 26px; padding: .15rem .38rem; font-size: .78rem; }
.vector-picker button[data-remove-vector] { display: grid; place-items: center; }
.vector-picker button:disabled { opacity: .35; cursor: default; }
.vector-picker button svg { width: 16px; height: 16px; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }
.calculation-panel__formula-layout { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr); column-gap: .8rem; row-gap: .45rem; align-items: start; }
.calculation-panel__formula-layout strong { overflow-wrap: anywhere; }
.calculation-panel__formula-components > span { margin: 0 0 .25rem; color: #c4f5eb; font-family: Georgia, serif; font-size: .7rem; font-weight: 500; letter-spacing: normal; text-transform: none; line-height: 1.5; overflow-wrap: anywhere; }
.calculation-panel__formula-layout.is-long { grid-template-columns: 1fr; gap: .4rem; }
@media (max-width: 430px) {
    .calculation-panel__formula-layout { grid-template-columns: 1fr; gap: .4rem; }
}