html, body {
    margin: 0;
    background-color: #333;
    color: #aaa;
    min-height: 100%;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
}

.Sandbox {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    padding: 0.75rem;
    box-sizing: border-box;
}

/* ---- Game shell (stable layout) ---- */

.Game {
    width: 100%;
    max-width: 1480px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

/* ---- App header ---- */

.AppHeader {
    position: sticky;
    top: 0;
    z-index: 10;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    min-height: 48px;
    padding: 0.4rem 0.75rem;
    background: #232323;
    border: 1px solid #3a3a3a;
    border-radius: 12px;
    box-sizing: border-box;
    flex-wrap: wrap;
}

.AppHeader__brand {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: #eaeaea;
    font-size: 0.95rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    flex: 0 0 auto;
}

.AppHeader__brand .BrandIcon {
    display: block;
    flex: 0 0 auto;
}

.AppHeader__status {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.6rem 0.9rem;
    flex: 1 1 auto;
    min-width: 0;
    margin: 0 auto;
    color: #b6b6b6;
    font-size: 0.82rem;
}

.AppHeader__stat {
    display: inline-flex;
    align-items: center;
    white-space: nowrap;
}

.AppHeader__status .Dot {
    display: inline-block;
    width: 0.55rem;
    height: 0.55rem;
    border-radius: 50%;
    margin-right: 0.3rem;
    vertical-align: middle;
    border: 1px solid #555;
}

.AppHeader__status .Dot.black {
    background: #111;
    border-color: #000;
}

.AppHeader__status .Dot.white {
    background: #fafafa;
    border-color: #888;
}

.AppHeader__status strong {
    color: #eaeaea;
    font-weight: 600;
}

.AppHeader__actions {
    display: inline-flex;
    align-items: center;
    gap: 0.32rem;
    flex: 0 0 auto;
    margin-left: auto;
}

.SidebarToggle {
    background: transparent;
    color: #b6b6b6;
    border: 1px solid #454545;
    border-radius: 8px;
    width: 32px;
    height: 32px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    line-height: 1;
    cursor: pointer;
    transition:
        background 0.12s,
        color 0.12s;
}

.SidebarToggle:hover {
    background: #2c2c2c;
    color: #e6e6e6;
}

/* ---- App shell + sidebar ---- */

.AppShell {
    display: flex;
    align-items: stretch;
    gap: 1rem;
    width: 100%;
    min-width: 0;
}

.Sidebar {
    flex: 0 0 240px;
    width: 240px;
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
    background: #232323;
    border: 1px solid #3a3a3a;
    border-radius: 12px;
    padding: 0.8rem;
    box-sizing: border-box;
    transition:
        flex-basis 0.18s ease,
        width 0.18s ease,
        margin 0.18s ease,
        padding 0.18s ease,
        opacity 0.18s ease;
}

.Sidebar--collapsed {
    flex: 0 0 0;
    width: 0;
    margin-left: -1rem;
    padding-left: 0;
    padding-right: 0;
    border-width: 0;
    opacity: 0;
    overflow: hidden;
    pointer-events: none;
}

.SidebarSection {
    display: flex;
    flex-direction: column;
    gap: 0.45rem;
}

.SidebarSection + .SidebarSection {
    border-top: 1px solid #333;
    padding-top: 0.75rem;
}

.SidebarSectionTitle {
    color: #6f6f6f;
    font-size: 0.62rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.09em;
}

.SidebarRow {
    display: flex;
    align-items: center;
    gap: 0.4rem;
}

.SidebarRow > .Dropdown,
.SidebarRow > .Segmented,
.SidebarRow > .Toggle {
    width: 100%;
}

.SidebarRow > .Segmented {
    display: flex;
}

.SidebarRow > .Segmented button {
    flex: 1;
}

.SidebarRow > .Dropdown select {
    flex: 1;
    width: 100%;
}

.SidebarRow .KomiInput {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    color: #888;
    font-size: 0.78rem;
    width: 100%;
}

.SidebarRow .KomiInput input {
    flex: 1;
    width: 100%;
    background: #1a1a1a;
    color: #dadada;
    border: 1px solid #454545;
    border-radius: 6px;
    padding: 0.3rem 0.45rem;
    font: inherit;
    font-size: 0.82rem;
}

.SidebarCredits {
    margin-top: auto;
    padding-top: 0.75rem;
    border-top: 1px solid #333;
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    font-size: 0.7rem;
    color: #6f6f6f;
}

.SidebarCredits a {
    color: #888;
    text-decoration: none;
}

.SidebarCredits a:hover {
    color: #dadada;
    text-decoration: underline;
}

.MainColumn {
    flex: 1 1 auto;
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

/* Segmented (mutually-exclusive) control */
.Segmented {
    display: inline-flex;
    background: #1a1a1a;
    border: 1px solid #454545;
    border-radius: 8px;
    overflow: hidden;
}

.Segmented button {
    background: transparent;
    color: #b6b6b6;
    border: none;
    border-left: 1px solid #383838;
    padding: 0.34rem 0.56rem;
    font: inherit;
    font-size: 0.79rem;
    line-height: 1.15;
    cursor: pointer;
    transition:
        background 0.12s,
        color 0.12s;
}

.Segmented button:first-child {
    border-left: none;
}

.Segmented button:hover:not(:disabled):not(.active) {
    background: #2c2c2c;
    color: #e6e6e6;
}

.Segmented button.active {
    background: #e7e7e7;
    color: #1a1a1a;
    font-weight: 600;
}

.Segmented button:disabled {
    opacity: 0.3;
    cursor: default;
}

/* Labeled dropdown (native select) */
.Dropdown {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    background: #1a1a1a;
    border: 1px solid #454545;
    border-radius: 8px;
    padding: 0.32rem 0.45rem 0.32rem 0.6rem;
    cursor: pointer;
    transition: background 0.12s;
}

.Dropdown:hover:not(.disabled) {
    background: #2c2c2c;
}

.DropdownLabel {
    color: #6f6f6f;
    font-size: 0.62rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.07em;
}

.Dropdown select {
    appearance: none;
    -webkit-appearance: none;
    background: transparent;
    color: #dadada;
    border: none;
    font: inherit;
    font-size: 0.8rem;
    line-height: 1.15;
    padding: 0 1rem 0 0;
    cursor: pointer;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 10 6'%3E%3Cpath d='M1 1l4 4 4-4' fill='none' stroke='%23999' stroke-width='1.4' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0 center;
    background-size: 0.62rem;
}

.Dropdown select:focus {
    outline: none;
}

.Dropdown select option {
    background: #232323;
    color: #dadada;
}

.Dropdown.disabled {
    opacity: 0.35;
}

.Dropdown.disabled select {
    cursor: default;
}

/* Standalone on/off toggle */
.Toggle {
    display: inline-flex;
    align-items: center;
    gap: 0.38rem;
    background: #1a1a1a;
    color: #b6b6b6;
    border: 1px solid #454545;
    border-radius: 8px;
    padding: 0.34rem 0.58rem 0.34rem 0.5rem;
    font: inherit;
    font-size: 0.79rem;
    line-height: 1.15;
    cursor: pointer;
    transition:
        background 0.12s,
        color 0.12s,
        border-color 0.12s;
}

.Toggle::before {
    content: "";
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: #555;
    transition:
        background 0.12s,
        box-shadow 0.12s;
}

.Toggle:hover:not(:disabled):not(.active) {
    background: #2c2c2c;
    color: #e6e6e6;
}

.Toggle.active {
    background: #15323d;
    border-color: #39d0ff;
    color: #cdeefb;
}

.Toggle.active::before {
    background: #39d0ff;
    box-shadow: 0 0 5px #39d0ff;
}

.Toggle:disabled {
    opacity: 0.3;
    cursor: default;
}

/* Action buttons (Pass / Reset / dialog actions) */
.ToolAction {
    background: transparent;
    color: #b6b6b6;
    border: 1px solid #454545;
    border-radius: 8px;
    padding: 0.34rem 0.62rem;
    font: inherit;
    font-size: 0.79rem;
    line-height: 1.15;
    cursor: pointer;
    transition:
        background 0.12s,
        color 0.12s;
}

.ToolAction:hover {
    background: #2c2c2c;
    color: #e6e6e6;
}

.ToolAction.Wide {
    width: 100%;
    text-align: center;
}

.Board {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    min-width: 0;
}

/* ---- 2D slices ---- */

.Slices {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
    max-width: 100%;
}

.Slice {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.3rem;
}

.SliceLabel {
    font-size: 0.75rem;
    color: #888;
    letter-spacing: 0.05em;
}

.SliceSvg {
    background: #dcb35c;
    border-radius: 6px;
    display: block;
}

.SlicePanelArea {
    width: 600px;
    max-width: 100%;
    height: 560px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.SliceGrid {
    display: grid;
    align-content: center;
    justify-content: center;
    justify-items: center;
    align-items: center;
}

.Slice.current .SliceSvg {
    box-shadow: 0 0 0 2px #39d0ff;
}

.Slice.current .SliceLabel {
    color: #39d0ff;
}

/* ---- Lattice view ---- */

.LatticeLayout {
    display: flex;
    gap: 1.25rem;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    width: 100%;
    min-width: 0;
}

.LatticeMount {
    width: 640px;
    max-width: 100%;
    height: min(600px, 70vh);
    aspect-ratio: 16 / 15;
    flex: 1 1 360px;
    border-radius: 12px;
    overflow: hidden;
    touch-action: none;
}

.SidePanel {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.SidePanelHeader {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    color: #ccc;
    font-size: 0.85rem;
}

.SidePanelHeader button {
    background: #1c1c1c;
    color: #aaa;
    border: 1px solid #555;
    width: 1.9rem;
    height: 1.9rem;
    font: inherit;
    cursor: pointer;
    border-radius: 5px;
    line-height: 1;
}

.SidePanelHeader button:disabled {
    opacity: 0.4;
    cursor: default;
}

/* ---- Status ---- */

.Status {
    display: flex;
    gap: 1.5rem;
    align-items: center;
    color: #ccc;
    font-size: 0.9rem;
    flex-wrap: wrap;
}

.Status .Hint {
    color: #777;
    font-size: 0.8rem;
}

.Status .Error {
    color: #e57373;
    font-style: italic;
}

.ScorePanel {
    display: flex;
    align-items: center;
    gap: 1.25rem;
    flex-wrap: wrap;
    justify-content: center;
    background: #262626;
    border: 1px solid #444;
    border-radius: 10px;
    padding: 0.6rem 0.9rem;
    color: #ccc;
    font-size: 0.9rem;
}

.ScorePanel .ScoreMode {
    color: #39d0ff;
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.75rem;
    letter-spacing: 0.06em;
}

.ScorePanel .ScoreResult {
    color: #fff;
    font-size: 1rem;
}

/* ---- Confirmation dialog ---- */

.DialogBackdrop {
    position: fixed;
    inset: 0;
    z-index: 100;
    background: rgba(0, 0, 0, 0.55);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    box-sizing: border-box;
    animation: dialog-fade 0.12s ease-out;
}

.Dialog {
    background: #262626;
    border: 1px solid #444;
    border-radius: 12px;
    padding: 1.25rem 1.25rem 1rem;
    width: min(420px, 100%);
    box-sizing: border-box;
    box-shadow: 0 14px 40px rgba(0, 0, 0, 0.45);
    color: #d8d8d8;
    animation: dialog-pop 0.14s ease-out;
}

.DialogTitle {
    margin: 0 0 0.35rem;
    font-size: 1rem;
    color: #eee;
    font-weight: 600;
}

.DialogMessage {
    margin: 0 0 1rem;
    color: #b0b0b0;
    font-size: 0.85rem;
    line-height: 1.4;
}

.DialogActions {
    display: flex;
    justify-content: flex-end;
    gap: 0.5rem;
}

.DialogConfirm {
    background: #3a7bd5;
    color: #fff;
    border: 1px solid #3a7bd5;
    border-radius: 8px;
    padding: 0.4rem 0.95rem;
    font: inherit;
    font-size: 0.82rem;
    font-weight: 600;
    line-height: 1.15;
    cursor: pointer;
    transition:
        background 0.12s,
        border-color 0.12s;
}

.DialogConfirm:hover {
    background: #4a8be5;
    border-color: #4a8be5;
}

@keyframes dialog-fade {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes dialog-pop {
    from {
        opacity: 0;
        transform: translateY(6px) scale(0.98);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

/* ---- Responsive breakpoints ---- */

@media (max-width: 900px) {
    .Sandbox {
        padding: 0.5rem;
    }

    .AppShell {
        flex-direction: column;
        gap: 0.6rem;
    }

    .Sidebar {
        flex: 0 0 auto;
        width: 100%;
        flex-direction: row;
        flex-wrap: wrap;
        gap: 0.6rem 1rem;
    }

    .SidebarSection {
        flex: 1 1 180px;
        min-width: 160px;
    }

    .SidebarSection + .SidebarSection {
        border-top: none;
        padding-top: 0;
    }

    .Sidebar--collapsed {
        margin-left: 0;
        margin-top: -0.6rem;
        padding-top: 0;
        padding-bottom: 0;
        max-height: 0;
    }

    .AppHeader__stat--prisoners {
        display: none;
    }
}

@media (max-width: 600px) {
    .Sandbox {
        padding: 0.4rem;
    }

    .Game {
        gap: 0.5rem;
    }

    .AppHeader {
        gap: 0.5rem;
        padding: 0.4rem 0.55rem;
    }

    .AppHeader__brand span:not(.Mark) {
        display: none;
    }

    .AppHeader__status {
        font-size: 0.78rem;
        gap: 0.45rem 0.7rem;
    }

    .AppHeader__stat--move {
        display: none;
    }

    .AppHeader__actions .ToolAction {
        padding: 0.3rem 0.5rem;
        font-size: 0.75rem;
    }

    .Sidebar {
        padding: 0.65rem;
        gap: 0.55rem 0.8rem;
    }

    .SidebarSection {
        flex: 1 1 140px;
    }

    .LatticeMount {
        height: min(70vw, 70vh);
        aspect-ratio: auto;
    }

    .SlicePanelArea {
        width: 100%;
        height: auto;
        min-height: 280px;
        overflow: auto;
    }

    .Slices {
        gap: 0.6rem;
    }

    .ScorePanel {
        gap: 0.6rem;
        font-size: 0.82rem;
        padding: 0.5rem 0.6rem;
    }
}