:root {
    color-scheme: dark;
    --panel-bg: rgba(8, 18, 36, 0.72);
    --panel-border: rgba(111, 179, 255, 0.28);
    --text: rgba(255, 255, 255, 0.94);
    --muted: rgba(214, 229, 255, 0.62);
    --accent: #69b7ff;
    --accent-strong: #8dd3ff;
    --surface: rgba(255, 255, 255, 0.055);
    --surface-strong: rgba(255, 255, 255, 0.09);
    --radius-lg: 20px;
    --radius-md: 16px;
    --radius-sm: 13px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    overflow: hidden;
    background: black;
    color: var(--text);
    font-family:
        Inter,
        ui-sans-serif,
        system-ui,
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        sans-serif;
}

canvas#bg {
    position: fixed;
    inset: 0;
    z-index: -1;
    display: block;
}

/* ---------------------------------------------------------- Control panel */

.dbg-panel {
    position: fixed;
    top: 1rem;
    right: 1rem;
    width: min(20rem, calc(100vw - 2rem));
    max-height: calc(100vh - 2rem);
    padding: 0.75rem;
    color: var(--text);
    border: 1px solid var(--panel-border);
    border-radius: var(--radius-lg);
    background:
        radial-gradient(
            circle at 12% 0%,
            rgba(105, 183, 255, 0.18),
            transparent 32%
        ),
        linear-gradient(
            145deg,
            rgba(10, 22, 43, 0.9),
            var(--panel-bg)
        );
    box-shadow:
        0 20px 60px rgba(0, 0, 0, 0.42),
        inset 0 1px 0 rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(18px) saturate(140%);
    -webkit-backdrop-filter: blur(18px) saturate(140%);
    display: grid;
    gap: 0.65rem;
    overflow: auto;
    scrollbar-width: thin;
    scrollbar-color: rgba(105, 183, 255, 0.45) transparent;
    user-select: none;
}

.dbg-panel::-webkit-scrollbar {
    width: 0.35rem;
}

.dbg-panel::-webkit-scrollbar-thumb {
    border-radius: 999px;
    background: rgba(105, 183, 255, 0.45);
}

.dbg-panel__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    padding: 0.1rem 0.1rem 0.2rem;
}

.dbg-panel__title {
    display: grid;
    gap: 0.18rem;
    min-width: 0;
}

.dbg-panel__title h2 {
    color: var(--text);
    font-size: 0.82rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    line-height: 1;
    text-transform: uppercase;
}

.dbg-panel__subtitle {
    color: var(--muted);
    font-size: 0.68rem;
    line-height: 1.2;
}

.dbg-panel__actions {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    flex-shrink: 0;
}

.dbg-panel__status {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.28rem 0.5rem;
    color: rgba(255, 255, 255, 0.82);
    font-size: 0.66rem;
    font-weight: 700;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    border: 1px solid rgba(72, 240, 164, 0.2);
    border-radius: 999px;
    background: rgba(72, 240, 164, 0.08);
}

.dbg-panel__status::before {
    content: "";
    width: 0.46rem;
    height: 0.46rem;
    border-radius: 999px;
    background: #48f0a4;
    box-shadow: 0 0 0 4px rgba(72, 240, 164, 0.12);
}

.dbg-panel__reset {
    appearance: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 1.75rem;
    padding: 0 0.7rem;
    color: rgba(255, 255, 255, 0.88);
    font-size: 0.66rem;
    font-weight: 700;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 999px;
    background: var(--surface);
    cursor: pointer;
    transition:
        background 160ms ease,
        border-color 160ms ease,
        color 160ms ease,
        transform 160ms ease;
}

.dbg-panel__reset:hover,
.dbg-panel__reset:focus-visible {
    color: #061121;
    border-color: transparent;
    background: linear-gradient(
        135deg,
        var(--accent),
        var(--accent-strong)
    );
    outline: none;
}

.dbg-panel__reset:active {
    transform: translateY(1px);
}

.dbg-panel__body {
    display: grid;
    gap: 0.55rem;
}

/* ----------------------------------------------------- Sections (details) */

.dbg-section {
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.04);
    overflow: hidden;
}

.dbg-section__summary {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    padding: 0.66rem 0.72rem;
    color: rgba(255, 255, 255, 0.88);
    font-size: 0.76rem;
    font-weight: 800;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    cursor: pointer;
    list-style: none;
}

.dbg-section__summary::-webkit-details-marker {
    display: none;
}

.dbg-section__title {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.dbg-section__chevron {
    display: grid;
    place-items: center;
    width: 1.25rem;
    height: 1.25rem;
    color: #061121;
    font-weight: 900;
    line-height: 1;
    border-radius: 999px;
    background: linear-gradient(135deg, var(--accent), var(--accent-strong));
    box-shadow: 0 6px 18px rgba(105, 183, 255, 0.18);
    transition: transform 180ms ease;
}

.dbg-section__chevron::after {
    content: "+";
    font-size: 0.9rem;
}

.dbg-section[open] > .dbg-section__summary .dbg-section__chevron::after {
    content: "−";
}

.dbg-section__content {
    display: grid;
    gap: 0.5rem;
    padding: 0 0.62rem 0.62rem;
}

.dbg-section__content--grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

/* --------------------------------------------------------------- Controls */

.dbg-control {
    display: grid;
    gap: 0.38rem;
    padding: 0.58rem;
    border: 1px solid rgba(255, 255, 255, 0.07);
    border-radius: var(--radius-sm);
    background: var(--surface);
    min-width: 0;
}

.dbg-section__content--grid .dbg-control--switch {
    grid-column: 1 / -1;
}

.dbg-control--switch {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
}

.dbg-control__label {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.6rem;
    color: var(--muted);
    font-size: 0.74rem;
    font-weight: 700;
    line-height: 1.15;
    min-width: 0;
}

.dbg-control--switch .dbg-control__label {
    flex: 1 1 auto;
}

.dbg-control__label-text {
    display: grid;
    gap: 0.16rem;
    min-width: 0;
}

.dbg-control__label-text > span:first-child {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.dbg-control__hint {
    color: rgba(214, 229, 255, 0.46);
    font-size: 0.64rem;
    font-weight: 600;
}

.dbg-control__value {
    min-width: 2.15rem;
    padding: 0.14rem 0.4rem;
    color: #061121;
    text-align: center;
    font-size: 0.68rem;
    font-variant-numeric: tabular-nums;
    border-radius: 999px;
    background: linear-gradient(135deg, var(--accent), var(--accent-strong));
    box-shadow: 0 6px 18px rgba(105, 183, 255, 0.18);
}

input[type="range"].dbg-control__range {
    width: 100%;
    height: 0.3rem;
    appearance: none;
    border: 0;
    border-radius: 999px;
    outline: none;
    cursor: pointer;
    background: linear-gradient(
        90deg,
        var(--accent),
        rgba(255, 255, 255, 0.16)
    );
}

input[type="range"].dbg-control__range::-webkit-slider-thumb {
    width: 0.86rem;
    height: 0.86rem;
    appearance: none;
    border: 2px solid rgba(255, 255, 255, 0.88);
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 0 4px rgba(105, 183, 255, 0.14);
    transition:
        transform 160ms ease,
        box-shadow 160ms ease;
}

input[type="range"].dbg-control__range::-moz-range-thumb {
    width: 0.72rem;
    height: 0.72rem;
    border: 2px solid rgba(255, 255, 255, 0.88);
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 0 4px rgba(105, 183, 255, 0.14);
    transition:
        transform 160ms ease,
        box-shadow 160ms ease;
}

input[type="range"].dbg-control__range:hover::-webkit-slider-thumb,
input[type="range"].dbg-control__range:focus-visible::-webkit-slider-thumb {
    transform: scale(1.08);
    box-shadow: 0 0 0 6px rgba(105, 183, 255, 0.2);
}

input[type="range"].dbg-control__range:hover::-moz-range-thumb,
input[type="range"].dbg-control__range:focus-visible::-moz-range-thumb {
    transform: scale(1.08);
    box-shadow: 0 0 0 6px rgba(105, 183, 255, 0.2);
}

input[type="color"].dbg-control__color {
    width: 100%;
    height: 2.4rem;
    padding: 0.24rem;
    appearance: none;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 0.85rem;
    background: var(--surface-strong);
    cursor: pointer;
}

input[type="color"].dbg-control__color::-webkit-color-swatch-wrapper {
    padding: 0;
}

input[type="color"].dbg-control__color::-webkit-color-swatch {
    border: 0;
    border-radius: 0.62rem;
}

input[type="color"].dbg-control__color::-moz-color-swatch {
    border: 0;
    border-radius: 0.62rem;
}

input[type="checkbox"].dbg-control__switch {
    position: relative;
    flex: 0 0 auto;
    width: 2.55rem;
    height: 1.35rem;
    appearance: none;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 999px;
    background: var(--surface-strong);
    cursor: pointer;
    transition:
        background 180ms ease,
        border-color 180ms ease;
}

input[type="checkbox"].dbg-control__switch::after {
    content: "";
    position: absolute;
    top: 0.17rem;
    left: 0.17rem;
    width: 0.92rem;
    height: 0.92rem;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.86);
    transition: transform 180ms ease;
}

input[type="checkbox"].dbg-control__switch:checked {
    border-color: rgba(105, 183, 255, 0.58);
    background: rgba(105, 183, 255, 0.34);
}

input[type="checkbox"].dbg-control__switch:checked::after {
    transform: translateX(1.2rem);
    background: var(--accent-strong);
}

/* -------------------------------------------------------------------- FPS */

.fps-counter {
    position: fixed;
    left: 1rem;
    top: 1rem;
    z-index: 1;
    min-width: 4.6rem;
    padding: 0.38rem 0.58rem;
    color: rgba(255, 255, 255, 0.88);
    font-size: 0.72rem;
    font-weight: 800;
    font-variant-numeric: tabular-nums;
    letter-spacing: 0.06em;
    text-align: center;
    text-transform: uppercase;
    border: 1px solid rgba(105, 183, 255, 0.24);
    border-radius: 999px;
    background: rgba(8, 18, 36, 0.64);
    box-shadow: 0 10px 28px rgba(0, 0, 0, 0.26);
    backdrop-filter: blur(14px) saturate(130%);
    -webkit-backdrop-filter: blur(14px) saturate(130%);
    pointer-events: none;
    user-select: none;
}

/* ---------------------------------------------------- Mobile adjustments */

@media (max-width: 520px) {
    .dbg-panel {
        top: 0.75rem;
        right: 0.75rem;
        left: 0.75rem;
        width: auto;
    }

    .dbg-section__content--grid {
        grid-template-columns: 1fr;
    }
}

@media (prefers-reduced-motion: reduce) {
    .dbg-panel__reset,
    .dbg-section__chevron,
    input[type="range"].dbg-control__range::-webkit-slider-thumb,
    input[type="range"].dbg-control__range::-moz-range-thumb,
    input[type="checkbox"].dbg-control__switch,
    input[type="checkbox"].dbg-control__switch::after {
        transition: none;
    }
}