:root {
    --space-0: #02030a;
    --space-1: #070b1d;
    --ink: #f7f8ff;
    --muted: #aab3d2;
    --origin: #ffe7ad;
    --physics: #55d6ff;
    --astronomy: #b78cff;
    --chemistry: #ffc65c;
    --biology: #62efa5;
    --counter-scale: 2.1739;
}

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

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

body {
    background: var(--space-0);
    color: var(--ink);
    font-family: "Inter", sans-serif;
}

button,
a {
    -webkit-tap-highlight-color: transparent;
}

button {
    color: inherit;
    font: inherit;
}

.deep-space {
    position: fixed;
    inset: 0;
    background:
        radial-gradient(circle at 50% 48%, rgba(65, 75, 160, .16), transparent 34%),
        radial-gradient(circle at 78% 22%, rgba(102, 52, 150, .13), transparent 30%),
        radial-gradient(circle at 19% 78%, rgba(24, 112, 96, .09), transparent 27%),
        linear-gradient(160deg, var(--space-1), var(--space-0) 48%, #03040d);
    pointer-events: none;
}

.deep-space::before,
.deep-space::after {
    content: "";
    position: absolute;
    inset: 0;
    background-image:
        radial-gradient(circle, rgba(255,255,255,.85) 0 1px, transparent 1.3px),
        radial-gradient(circle, rgba(156,181,255,.55) 0 1px, transparent 1.2px);
    background-position: 0 0, 31px 47px;
    background-size: 83px 83px, 127px 127px;
    opacity: .23;
}

.deep-space::after {
    background-size: 211px 211px, 293px 293px;
    filter: blur(.25px);
    opacity: .35;
    transform: rotate(12deg) scale(1.15);
}

/* Introdução curta, preservando a narrativa original. */
.intro-layer {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: grid;
    place-items: center;
    overflow: hidden;
    background: #020309;
    transition: opacity .8s ease, visibility .8s ease;
}

.intro-layer.is-finished {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.intro-copy {
    position: relative;
    z-index: 2;
    width: min(760px, calc(100vw - 48px));
    min-height: 170px;
    display: grid;
    place-items: center;
    text-align: center;
}

.intro-kicker {
    position: absolute;
    top: -42px;
    color: #8691b5;
    font-size: .75rem;
    font-weight: 700;
    letter-spacing: .22em;
    text-transform: uppercase;
}

.intro-texto,
.intro-final {
    position: absolute;
    display: none;
    justify-content: center;
    flex-wrap: wrap;
    font-family: "Space Grotesk", sans-serif;
    font-size: clamp(1.65rem, 5vw, 3.7rem);
    font-weight: 600;
    letter-spacing: -.035em;
    line-height: 1.08;
}

.intro-final {
    color: var(--origin);
    font-size: clamp(2.7rem, 8vw, 6rem);
    text-shadow: 0 0 28px rgba(255, 196, 118, .45);
}

.intro-texto span,
.intro-final span {
    opacity: 0;
    transition: opacity .35s ease;
}

.intro-orbit {
    position: absolute;
    width: min(70vw, 720px);
    aspect-ratio: 1;
    border: 1px solid rgba(174, 188, 255, .12);
    border-radius: 50%;
    box-shadow: 0 0 120px rgba(88, 77, 180, .12) inset;
    animation: intro-orbit 18s linear infinite;
}

.intro-orbit::before,
.intro-orbit::after {
    content: "";
    position: absolute;
    border-radius: 50%;
}

.intro-orbit::before {
    inset: 16%;
    border: 1px solid rgba(255, 231, 173, .1);
}

.intro-orbit::after {
    width: 8px;
    height: 8px;
    top: 12%;
    left: 21%;
    background: var(--origin);
    box-shadow: 0 0 18px var(--origin);
}

@keyframes intro-orbit {
    to { transform: rotate(360deg); }
}

.skip-intro {
    position: absolute;
    right: 24px;
    bottom: 24px;
    z-index: 3;
    padding: 10px 14px;
    border: 1px solid rgba(255,255,255,.14);
    border-radius: 999px;
    background: rgba(12, 16, 36, .72);
    color: var(--muted);
    cursor: pointer;
}

.skip-intro:hover,
.skip-intro:focus-visible {
    border-color: rgba(255,255,255,.35);
    color: #fff;
}

/* Interface flutuante */
.ui-layer {
    position: fixed;
    top: 22px;
    left: 24px;
    right: 24px;
    z-index: 80;
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    pointer-events: none;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    color: var(--ink);
    text-decoration: none;
    pointer-events: auto;
}

.brand-mark {
    width: 34px;
    height: 34px;
    border: 1px solid rgba(255,255,255,.28);
    border-radius: 50%;
    background:
        radial-gradient(circle at 50% 50%, var(--origin) 0 2px, transparent 3px),
        radial-gradient(circle at 28% 36%, var(--physics) 0 1px, transparent 2px),
        radial-gradient(circle at 70% 62%, var(--biology) 0 1px, transparent 2px);
    box-shadow: 0 0 22px rgba(255,231,173,.2);
}

.brand strong,
.brand small {
    display: block;
}

.brand strong {
    font-family: "Space Grotesk", sans-serif;
    font-size: .95rem;
    letter-spacing: -.02em;
}

.brand small {
    margin-top: 1px;
    color: var(--muted);
    font-size: .68rem;
    letter-spacing: .16em;
    text-transform: uppercase;
}

.explore-hint,
.legend,
.map-controls,
.info-panel {
    border: 1px solid rgba(176, 190, 255, .14);
    background: rgba(7, 10, 26, .68);
    box-shadow: 0 16px 50px rgba(0,0,0,.24);
    backdrop-filter: blur(16px);
}

.explore-hint {
    padding: 10px 14px;
    border-radius: 999px;
    color: var(--muted);
    font-size: .75rem;
}

.touch-hint {
    display: none;
}

.legend {
    position: fixed;
    top: 84px;
    right: 24px;
    z-index: 80;
    min-width: 166px;
    padding: 14px;
    border-radius: 16px;
}

.legend p {
    margin-bottom: 10px;
    color: #7883a8;
    font-size: .68rem;
    font-weight: 700;
    letter-spacing: .13em;
    text-transform: uppercase;
}

.legend ul {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 9px 12px;
    list-style: none;
}

.legend li {
    display: flex;
    align-items: center;
    gap: 7px;
    color: #c8cee4;
    font-size: .72rem;
}

.legend-dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    box-shadow: 0 0 9px currentColor;
}

.legend-dot.fisica { color: var(--physics); background: currentColor; }
.legend-dot.astronomia { color: var(--astronomy); background: currentColor; }
.legend-dot.quimica { color: var(--chemistry); background: currentColor; }
.legend-dot.biologia { color: var(--biology); background: currentColor; }

.map-controls {
    position: fixed;
    left: 24px;
    bottom: 24px;
    z-index: 90;
    display: flex;
    align-items: center;
    padding: 5px;
    border-radius: 15px;
}

.map-controls button {
    width: 38px;
    height: 38px;
    border: 0;
    border-radius: 10px;
    background: transparent;
    color: #dce3ff;
    font-size: 1.15rem;
    cursor: pointer;
}

.map-controls button:hover,
.map-controls button:focus-visible {
    background: rgba(255,255,255,.1);
    outline: none;
}

.map-controls .reset-view {
    border-left: 1px solid rgba(255,255,255,.1);
    border-radius: 0 10px 10px 0;
}

#zoom-status {
    min-width: 48px;
    padding: 0 8px;
    color: #7f89aa;
    font-size: .7rem;
    text-align: center;
}

/* Universo navegável */
.viewport {
    position: fixed;
    inset: 0;
    overflow: hidden;
    cursor: grab;
    outline: none;
    touch-action: none;
}

.viewport.is-dragging { cursor: grabbing; }

.viewport:focus-visible::after {
    content: "";
    position: fixed;
    inset: 8px;
    z-index: 70;
    border: 1px solid rgba(110, 180, 255, .45);
    border-radius: 18px;
    pointer-events: none;
}

.universe {
    position: absolute;
    top: 0;
    left: 0;
    width: 3600px;
    height: 2800px;
    overflow: hidden;
    transform-origin: 0 0;
    will-change: transform;
}

.nebula {
    position: absolute;
    border-radius: 50%;
    opacity: .34;
    filter: blur(80px);
    pointer-events: none;
}

.nebula-a {
    width: 1050px;
    height: 720px;
    left: 2000px;
    top: 250px;
    background: radial-gradient(ellipse, rgba(126, 80, 214, .3), rgba(49, 69, 173, .09) 52%, transparent 72%);
    transform: rotate(-22deg);
}

.nebula-b {
    width: 1100px;
    height: 680px;
    left: 260px;
    top: 1500px;
    background: radial-gradient(ellipse, rgba(27, 166, 119, .23), rgba(28, 88, 124, .08) 55%, transparent 72%);
    transform: rotate(18deg);
}

.nebula-c {
    width: 920px;
    height: 620px;
    left: 360px;
    top: 360px;
    background: radial-gradient(ellipse, rgba(209, 138, 48, .15), rgba(104, 53, 125, .08) 56%, transparent 72%);
}

.background-star {
    position: absolute;
    width: var(--size);
    height: var(--size);
    border-radius: 50%;
    background: var(--star-color, #fff);
    opacity: var(--opacity);
    box-shadow: 0 0 var(--glow-size) currentColor;
    animation: twinkle var(--duration) ease-in-out var(--delay) infinite alternate;
}

@keyframes twinkle {
    from { opacity: var(--opacity-min); }
    to { opacity: var(--opacity); }
}

#lines-layer,
#nodes-layer,
#branch-labels {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
}

#lines-layer {
    overflow: visible;
    pointer-events: none;
}

.connection-glow,
.connection {
    fill: none;
    stroke: var(--line-color);
    stroke-linecap: round;
}

.connection-glow { stroke-width: 15px; opacity: .045; }

.connection {
    stroke-width: 2px;
    opacity: .44;
    filter: drop-shadow(0 0 5px var(--line-color));
}

.branch-title {
    position: absolute;
    color: var(--branch-color);
    font-family: "Space Grotesk", sans-serif;
    font-size: 1.2rem;
    font-weight: 600;
    letter-spacing: .2em;
    opacity: .36;
    text-transform: uppercase;
    transform: translate(-50%, -50%) scale(var(--counter-scale));
    transform-origin: center;
    text-shadow: 0 0 20px currentColor;
    white-space: nowrap;
}

.knowledge-node {
    --node-size: 25px;
    --label-offset: 23px;
    position: absolute;
    width: 48px;
    height: 48px;
    border: 0;
    background: transparent;
    cursor: pointer;
    transform: translate(-50%, -50%) scale(var(--counter-scale));
    transform-origin: center;
    z-index: 10;
}

.node-star {
    position: absolute;
    top: 50%;
    left: 50%;
    width: var(--node-size);
    height: var(--node-size);
    border: 1px solid color-mix(in srgb, var(--node-color) 75%, white);
    border-radius: 50%;
    background: radial-gradient(circle at 38% 35%, #fff 0 5%, var(--node-color) 19%, color-mix(in srgb, var(--node-color) 62%, #11162d) 57%, transparent 73%);
    box-shadow: 0 0 8px var(--node-color), 0 0 22px color-mix(in srgb, var(--node-color) 65%, transparent), 0 0 45px color-mix(in srgb, var(--node-color) 30%, transparent);
    transform: translate(-50%, -50%);
    transition: transform .22s ease, filter .22s ease;
}

.node-star::before,
.node-star::after {
    content: "";
    position: absolute;
    inset: 50% auto auto 50%;
    background: linear-gradient(90deg, transparent, var(--node-color), transparent);
    opacity: .35;
    transform: translate(-50%, -50%);
}

.node-star::before { width: 180%; height: 1px; }
.node-star::after { width: 1px; height: 180%; }

.knowledge-node[data-level="0"] { --node-size: 76px; --label-offset: 49px; z-index: 20; }
.knowledge-node[data-level="1"] { --node-size: 39px; --label-offset: 31px; z-index: 18; }
.knowledge-node[data-level="2"] { --node-size: 30px; --label-offset: 27px; }
.knowledge-node[data-level="3"] { --node-size: 23px; --label-offset: 23px; }

.knowledge-node[data-area="origem"] .node-star {
    animation: origin-pulse 3.4s ease-in-out infinite;
}

@keyframes origin-pulse {
    50% {
        box-shadow: 0 0 12px var(--node-color), 0 0 38px var(--node-color), 0 0 82px rgba(255, 203, 126, .34);
        transform: translate(-50%, -50%) scale(1.08);
    }
}

.knowledge-node:hover .node-star,
.knowledge-node:focus-visible .node-star,
.knowledge-node.is-active .node-star {
    filter: brightness(1.22);
    transform: translate(-50%, -50%) scale(1.16);
}

.knowledge-node:focus-visible {
    outline: 1px solid rgba(255,255,255,.65);
    outline-offset: 4px;
    border-radius: 50%;
}

.node-label {
    position: absolute;
    top: calc(50% + var(--label-offset));
    left: 50%;
    width: max-content;
    max-width: 170px;
    padding: 4px 7px;
    border: 1px solid transparent;
    border-radius: 7px;
    background: rgba(3, 5, 15, .52);
    color: #dfe4f8;
    font-family: "Space Grotesk", sans-serif;
    font-size: .72rem;
    font-weight: 500;
    line-height: 1.2;
    text-align: center;
    text-shadow: 0 1px 4px #000;
    transform: translateX(-50%);
    transition: border-color .2s ease, background .2s ease, color .2s ease;
}

.knowledge-node:hover .node-label,
.knowledge-node:focus-visible .node-label,
.knowledge-node.is-active .node-label {
    border-color: color-mix(in srgb, var(--node-color) 48%, transparent);
    background: rgba(5, 8, 22, .9);
    color: #fff;
}

.viewport[data-distance="far"] .knowledge-node[data-level="3"] .node-label { opacity: 0; }

/* Painel de leitura */
.info-panel {
    --panel-color: var(--origin);
    position: fixed;
    right: 24px;
    bottom: 24px;
    z-index: 120;
    width: min(390px, calc(100vw - 48px));
    padding: 22px;
    border-radius: 22px;
    overflow: hidden;
    animation: panel-in .28s ease both;
}

.info-panel[hidden] { display: none; }

.info-panel::before {
    content: "";
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--panel-color), transparent);
    box-shadow: 0 0 20px var(--panel-color);
}

@keyframes panel-in {
    from { opacity: 0; transform: translateY(12px); }
}

.close-panel {
    position: absolute;
    top: 14px;
    right: 14px;
    width: 34px;
    height: 34px;
    border: 0;
    border-radius: 50%;
    background: rgba(255,255,255,.07);
    color: #b7bfdc;
    font-size: 1.3rem;
    line-height: 1;
    cursor: pointer;
}

.close-panel:hover,
.close-panel:focus-visible {
    background: rgba(255,255,255,.13);
    color: #fff;
    outline: none;
}

.panel-meta {
    display: flex;
    align-items: center;
    gap: 9px;
    margin-bottom: 13px;
    padding-right: 38px;
}

.area-pill {
    padding: 5px 8px;
    border: 1px solid color-mix(in srgb, var(--panel-color) 42%, transparent);
    border-radius: 999px;
    background: color-mix(in srgb, var(--panel-color) 10%, transparent);
    color: var(--panel-color);
    font-size: .65rem;
    font-weight: 700;
    letter-spacing: .1em;
    text-transform: uppercase;
}

.scale-label { color: #7f89aa; font-size: .72rem; }

.info-panel h1 {
    margin-bottom: 10px;
    font-family: "Space Grotesk", sans-serif;
    font-size: clamp(1.55rem, 4vw, 2rem);
    letter-spacing: -.035em;
    line-height: 1.05;
}

.info-panel > p {
    color: #c3c9df;
    font-size: .94rem;
    line-height: 1.65;
}

.info-panel .connection-count {
    margin-top: 16px;
    padding-top: 13px;
    border-top: 1px solid rgba(255,255,255,.09);
    color: #747e9f;
    font-size: .72rem;
}

.source-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: 13px;
    color: var(--panel-color);
    font-size: .76rem;
    font-weight: 600;
    text-decoration: none;
}

.source-link:hover,
.source-link:focus-visible {
    text-decoration: underline;
    text-underline-offset: 4px;
    outline: none;
}

@media (max-width: 720px) {
    .ui-layer { top: 16px; left: 16px; right: 16px; }

    .explore-hint {
        max-width: 176px;
        border-radius: 13px;
        font-size: .68rem;
        line-height: 1.35;
        text-align: right;
    }

    .desktop-hint { display: none; }
    .touch-hint { display: inline; }

    .legend {
        top: auto;
        right: 16px;
        bottom: 16px;
        min-width: 0;
        padding: 10px 12px;
    }

    .legend p { display: none; }
    .legend ul { grid-template-columns: 1fr 1fr; gap: 7px 10px; }

    .map-controls {
        left: 16px;
        bottom: 16px;
        flex-wrap: wrap;
        width: 91px;
    }

    #zoom-status { width: 100%; padding: 5px 0 3px; }

    .info-panel {
        right: 12px;
        bottom: 100px;
        width: calc(100vw - 24px);
        padding: 19px;
    }

    .branch-title { font-size: .92rem; }
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        scroll-behavior: auto !important;
        animation-duration: .01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: .01ms !important;
    }
}