// ── Burger btn + fan-of-5 (room.html only) ───────────────────────────
//
// Sits parallel to .gear-btn-above-#id_kit_btn, but on the bud-side:
//   portrait : bottom-left, above #id_bud_btn
//   landscape: right sidebar, to the LEFT of #id_bud_btn (same horizontal
//              pair as gear ← kit at the top)
//
// Active state opens a fanning arc of 5 sub-btns 30deg apart, each
// centred --r from the burger centre. R=7.75rem reads as a comfortable
// spread w. ~0.4rem edge-to-edge gaps between adjacent sub-btns.
//   portrait : arc 12→4 o'clock (sky, earth, sea, voice, text)
//   landscape: arc 9→1 o'clock (same icon order, rotated CCW 90°)
//
// Sub-btns are pure scaffolding — no click handlers in this sprint.
//
// Landscape btn relocation rules for kit / gear / bud / kit_dialog / bud
// panel / applet menus DON'T live in this partial — they're owned by
// their respective `_game-kit.scss`, `_bud.scss`, `_applets.scss`,
// `_room.scss` partials. _burger.scss only owns burger-specific styling.

#id_burger_btn {
    position: fixed;
    bottom: 4.2rem;
    left: 0.5rem;
    // Match .gear-btn page-level z (314) — keeps burger BELOW kit_btn +
    // bud_btn (both z-318) + bud_panel (z-317) so those naturally cover
    // burger when they overlap. Dialog (z-316) covers burger too.
    z-index: 314;
    font-size: 1.75rem;
    cursor: pointer;
    color: rgba(var(--secUser), 1);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    background-color: rgba(var(--priUser), 1);
    border: 0.15rem solid rgba(var(--secUser), 1);
    transition: opacity 0.15s ease;

    &.active {
        color: rgba(var(--quaUser), 1);
        border-color: rgba(var(--quaUser), 1);
    }

    // Landscape: burger sits to the LEFT of #id_bud_btn (same bottom
    // anchor as bud). Mirrors gear-to-the-LEFT-of-kit at the top of the
    // right sidebar (see _applets.scss for the gear placement).
    @media (orientation: landscape) {
        left: auto;
        right: 4.2rem;        // bud_btn right (0.5) + 3.7rem centre-to-centre delta
        bottom: 0.5rem;
        top: auto;
    }
}

// Fan anchor — sits at the burger centre. Sub-btns inside translate
// outward radially when #id_burger_btn carries the .active class.
#id_burger_fan {
    position: fixed;
    bottom: 5.7rem;   // burger bottom (4.2) + half-btn (1.5)
    left: 2rem;       // burger left   (0.5) + half-btn (1.5)
    width: 0;
    height: 0;
    z-index: 313;     // below #id_burger_btn (314) so burger stays clickable
    pointer-events: none;

    @media (orientation: landscape) {
        left: auto;
        right: 5.7rem;        // burger right (4.2) + half-btn (1.5) → burger centre
        bottom: 2rem;         // burger bottom (0.5) + half-btn (1.5) → burger centre
        top: auto;
    }
}

.burger-fan-btn {
    --r: 7.75rem;
    --i: 0;
    --base: 0deg;      // portrait: arc starts at 12 o'clock
    --angle: calc(var(--base) + var(--i) * 30deg);

    position: absolute;
    left: -1.5rem;     // centre 3rem btn on parent's 0,0 origin
    top: -1.5rem;
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    background-color: rgba(var(--priUser), 1);
    border: 0.15rem solid rgba(var(--secUser), 1);
    color: rgba(var(--secUser), 1);
    font-size: 1.25rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;

    // Closed state — collapsed onto burger centre, invisible
    transform: rotate(var(--angle)) translateY(0) rotate(calc(-1 * var(--angle)));
    opacity: 0;
    pointer-events: none;
    transition: transform 0.25s ease-out, opacity 0.2s ease;

    // Landscape: arc rotates CCW 90° — start at 9 o'clock instead of 12.
    @media (orientation: landscape) {
        --base: -90deg;
    }
}

// Per-btn arc index (clockwise from arc start) — voice leads, then sky,
// earth, sea, text. Portrait arc: voice at 12, text at 4 o'clock.
// Landscape arc: voice at 9, text at 1 o'clock.
#id_voice_btn { --i: 0; }
#id_sky_btn   { --i: 1; }
#id_earth_btn { --i: 2; }
#id_sea_btn   { --i: 3; }
#id_text_btn  { --i: 4; }

// Open state — sub-btns swing out to their arc positions.
#id_burger_btn.active ~ #id_burger_fan .burger-fan-btn {
    transform: rotate(var(--angle)) translateY(calc(-1 * var(--r))) rotate(calc(-1 * var(--angle)));
    pointer-events: auto;
}

// Active sub-btn = fully visible; inactive (default) = 0.6 opacity hint.
// `z-index: 1` raises the active sub-btn above its inactive siblings so
// click hit-testing picks the active one even while the fan is mid-
// transition (during the 0.25s arc-out animation all 5 sub-btns share
// the fan-centre origin, and a later-in-DOM inactive btn would otherwise
// obscure the active target). Active conditions are wired one-by-one in
// later sprints.
#id_burger_btn.active ~ #id_burger_fan .burger-fan-btn.active {
    opacity: 1;
    z-index: 1;
}
#id_burger_btn.active ~ #id_burger_fan .burger-fan-btn:not(.active) {
    opacity: 0.6;
}

// Icon swap — every sub-btn renders BOTH the real icon (.burger-fan-icon--on)
// + a fa-ban placeholder (.burger-fan-icon--off). Real icon shows by
// default in BOTH .active + inactive states; fa-ban only surfaces during
// the .flash-inactive pulse below. Stacked absolute-position so swapping
// doesn't shift the layout box.
.burger-fan-btn {
    .burger-fan-icon--on,
    .burger-fan-icon--off {
        position: absolute;
        top: 50%;
        left: 50%;
        transform: translate(-50%, -50%);
    }
    .burger-fan-icon--on  { display: inline-block; }
    .burger-fan-icon--off { display: none; }
}

// Click-while-inactive flash — burger-btn.js toggles .flash-inactive
// twice in quick succession (~180ms on / 120ms off) for a brief --priRd
// glow on the border + icon, AND swaps the real icon for fa-ban during
// each pulse-on phase. Modeled on sig-select.js's SAVE SIG countdown
// glow but tighter cadence + only 2 pulses.
.burger-fan-btn.flash-inactive {
    border-color: rgba(var(--priRd), 1);
    color: rgba(var(--priRd), 1);
    box-shadow:
        0 0 0.5rem 0.1rem rgba(var(--priRd), 0.75),
        0 0 1.2rem 0.3rem rgba(var(--priRd), 0.35);

    .burger-fan-icon--on  { display: none; }
    .burger-fan-icon--off { display: inline-block; }
}

// ── First-draw glow handoff (phase 3 of the Sea sub-btn rollout) ─────
//
// Pre-first-draw nudge for the my-sea picker: a --priYl + --ninUser glow
// rides the affordance chain to teach the user where to click.
//
//   burger  →  click  →  sea_btn  →  click  →  .sea-select  →  click  →  end
//
// Modal close (Esc / backdrop / DEL) w/o AUTO DRAW restarts the cycle on
// the burger. AUTO DRAW's guard-OK ends the cycle permanently (the user
// has actually drawn — they've found the path). Owner: my_sea.html JS.
#id_burger_btn.glow-handoff,
#id_sea_btn.glow-handoff {
    color: rgba(var(--priYl), 1);
    border-color: rgba(var(--priYl), 1);
    box-shadow:
        0 0 0.5rem 0.1rem rgba(var(--ninUser), 0.75),
        0 0 1.2rem 0.3rem rgba(var(--ninUser), 0.35);
}

// Burger hides when bud_panel is open — LANDSCAPE only. In portrait the
// burger sits ABOVE the bud panel (bottom:4.2rem vs panel at bottom:0.5
// + height:3rem); no visual conflict. In landscape they share the
// bottom-right area + the bud OK btn ends up obscured / pointer-events
// races against the burger even at the lower z-index — explicit fade
// keeps the bud_panel apparatus clean.
@media (orientation: landscape) {
    html.bud-open #id_burger_btn {
        opacity: 0;
        pointer-events: none;
    }
}