:root {
    --bg-start: #040814;
    --bg-end: #0b1330;
    --ink: #f6fbff;
    --muted: rgba(219, 231, 255, 0.72);
    --line: rgba(255, 255, 255, 0.12);
    --glass: rgba(8, 15, 36, 0.54);
    --glow-a: #5dd6ff;
    --glow-b: #79ffb1;
    --glow-c: #ffe27a;
    --glow-d: #ff8a5b;
    --shadow: 0 24px 80px rgba(0, 0, 0, 0.45);
    --footer-height: 112px;
    --pointer-x: 50vw;
    --pointer-y: 50vh;
}

* {
    box-sizing: border-box;
}

html {
    height: 100%;
}

body {
    min-height: 100vh;
    margin: 0;
    overflow: hidden;
    font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    color: var(--ink);
    background:
        radial-gradient(circle at 20% 20%, rgba(93, 214, 255, 0.12), transparent 30%),
        radial-gradient(circle at 78% 16%, rgba(121, 255, 177, 0.08), transparent 22%),
        radial-gradient(circle at 50% 120%, rgba(255, 138, 91, 0.12), transparent 36%),
        linear-gradient(180deg, var(--bg-start) 0%, var(--bg-end) 58%, #030610 100%);
}

body::before {
    content: '';
    position: fixed;
    inset: 0;
    background:
        radial-gradient(circle 180px at var(--pointer-x) var(--pointer-y), rgba(93, 214, 255, 0.12), transparent 72%),
        radial-gradient(circle 240px at calc(var(--pointer-x) + 8%) calc(var(--pointer-y) - 6%), rgba(121, 255, 177, 0.08), transparent 70%);
    pointer-events: none;
    mix-blend-mode: screen;
    opacity: 0.9;
}

.space-scene,
.error-stage,
.footer-wrap {
    position: relative;
    z-index: 1;
}

.space-scene {
    position: fixed;
    inset: 0;
    overflow: hidden;
    pointer-events: none;
}

.starfield,
.nebula,
.orbit,
.planet,
.comet,
.dust-glow,
.stellar-wave {
    position: absolute;
}

.starfield {
    inset: -10%;
    background-repeat: repeat;
    animation: drift linear infinite;
    opacity: 0.85;
}

.starfield-far {
    background-image:
        radial-gradient(circle at 12% 18%, rgba(255, 255, 255, 0.65) 0 1px, transparent 1.4px),
        radial-gradient(circle at 44% 72%, rgba(162, 214, 255, 0.55) 0 1px, transparent 1.6px),
        radial-gradient(circle at 82% 28%, rgba(255, 255, 255, 0.45) 0 1px, transparent 1.5px),
        radial-gradient(circle at 72% 82%, rgba(121, 255, 177, 0.42) 0 1px, transparent 1.6px),
        radial-gradient(circle at 24% 86%, rgba(255, 226, 122, 0.35) 0 1px, transparent 1.5px);
    background-size: 340px 340px;
    animation-duration: 180s;
    opacity: 0.4;
}

.starfield-mid {
    background-image:
        radial-gradient(circle at 18% 24%, rgba(255, 255, 255, 0.82) 0 1.2px, transparent 1.9px),
        radial-gradient(circle at 54% 68%, rgba(93, 214, 255, 0.8) 0 1.1px, transparent 1.7px),
        radial-gradient(circle at 86% 42%, rgba(255, 255, 255, 0.72) 0 1.2px, transparent 1.8px),
        radial-gradient(circle at 66% 14%, rgba(121, 255, 177, 0.6) 0 1.1px, transparent 1.8px),
        radial-gradient(circle at 28% 76%, rgba(255, 226, 122, 0.5) 0 1.1px, transparent 1.7px);
    background-size: 240px 240px;
    animation-duration: 110s;
    opacity: 0.65;
}

.starfield-near {
    background-image:
        radial-gradient(circle at 22% 16%, rgba(255, 255, 255, 0.98) 0 1.8px, transparent 2.4px),
        radial-gradient(circle at 50% 58%, rgba(93, 214, 255, 0.95) 0 1.7px, transparent 2.4px),
        radial-gradient(circle at 84% 34%, rgba(255, 255, 255, 0.92) 0 1.9px, transparent 2.5px),
        radial-gradient(circle at 76% 78%, rgba(121, 255, 177, 0.72) 0 1.7px, transparent 2.3px),
        radial-gradient(circle at 14% 70%, rgba(255, 226, 122, 0.82) 0 1.7px, transparent 2.3px);
    background-size: 170px 170px;
    animation-duration: 70s;
    opacity: 0.8;
}

.nebula {
    width: 46vw;
    height: 46vw;
    filter: blur(22px);
    opacity: 0.48;
    border-radius: 50%;
    mix-blend-mode: screen;
    animation: pulseNebula 18s ease-in-out infinite;
}

.nebula-left {
    top: -8vw;
    left: -10vw;
    background: radial-gradient(circle, rgba(93, 214, 255, 0.24), rgba(93, 214, 255, 0.06) 42%, transparent 68%);
}

.nebula-right {
    right: -12vw;
    bottom: -16vw;
    background: radial-gradient(circle, rgba(255, 138, 91, 0.2), rgba(121, 255, 177, 0.06) 38%, transparent 70%);
    animation-delay: -9s;
}

.orbit {
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 999px;
    box-shadow: inset 0 0 30px rgba(255, 255, 255, 0.02);
}

.orbit-one {
    width: min(80vw, 1200px);
    height: min(80vw, 1200px);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) rotate(8deg);
}

.orbit-two {
    width: min(56vw, 860px);
    height: min(56vw, 860px);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) rotate(-12deg);
}

.planet {
    border-radius: 50%;
    box-shadow: var(--shadow);
    animation: floatPlanet 22s ease-in-out infinite;
    will-change: transform;
}

.planet::before,
.planet::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 50%;
}

.planet::before {
    background: radial-gradient(circle at 30% 28%, rgba(255, 255, 255, 0.6), transparent 24%);
    mix-blend-mode: screen;
}

.planet::after {
    inset: auto;
    width: 140%;
    height: 18%;
    left: -20%;
    top: 42%;
    border-radius: 999px;
    border: 1px solid rgba(255, 255, 255, 0.18);
    transform: rotate(-18deg);
    opacity: 0.7;
}

.planet-one {
    width: clamp(160px, 18vw, 260px);
    height: clamp(160px, 18vw, 260px);
    top: 12%;
    right: 10%;
    background:
        radial-gradient(circle at 28% 24%, rgba(255, 255, 255, 0.92), transparent 18%),
        radial-gradient(circle at 42% 40%, rgba(93, 214, 255, 0.95), rgba(44, 93, 255, 0.62) 58%, rgba(13, 19, 55, 0.9) 100%);
}

.planet-two {
    width: clamp(92px, 10vw, 150px);
    height: clamp(92px, 10vw, 150px);
    left: 8%;
    top: 18%;
    background:
        radial-gradient(circle at 34% 24%, rgba(255, 255, 255, 0.8), transparent 16%),
        radial-gradient(circle at 42% 42%, rgba(121, 255, 177, 0.96), rgba(29, 125, 101, 0.74) 58%, rgba(8, 24, 30, 0.94) 100%);
    animation-duration: 26s;
    animation-delay: -8s;
}

.planet-three {
    width: clamp(200px, 24vw, 360px);
    height: clamp(200px, 24vw, 360px);
    left: -4%;
    bottom: -8%;
    background:
        radial-gradient(circle at 36% 20%, rgba(255, 255, 255, 0.84), transparent 14%),
        radial-gradient(circle at 44% 38%, rgba(255, 226, 122, 0.95), rgba(255, 138, 91, 0.78) 52%, rgba(73, 22, 15, 0.95) 100%);
    animation-duration: 28s;
}

.planet-four {
    width: clamp(72px, 8vw, 122px);
    height: clamp(72px, 8vw, 122px);
    right: 18%;
    bottom: 20%;
    background:
        radial-gradient(circle at 38% 20%, rgba(255, 255, 255, 0.76), transparent 16%),
        radial-gradient(circle at 44% 42%, rgba(255, 170, 109, 0.95), rgba(169, 74, 224, 0.64) 56%, rgba(20, 12, 46, 0.95) 100%);
    animation-duration: 24s;
    animation-delay: -12s;
}

.comet {
    top: -18vh;
    left: -24vw;
    width: clamp(120px, 16vw, 220px);
    height: 2px;
    border-radius: 999px;
    background: linear-gradient(90deg, rgba(255, 255, 255, 0), rgba(255, 255, 255, 0.95) 40%, rgba(93, 214, 255, 0.25) 100%);
    box-shadow: 0 0 14px rgba(93, 214, 255, 0.35);
    opacity: 0;
    transform: rotate(-24deg);
}

.comet::before {
    content: '';
    position: absolute;
    right: -6px;
    top: 50%;
    width: 12px;
    height: 12px;
    transform: translateY(-50%);
    border-radius: 50%;
    background: radial-gradient(circle, rgba(255, 255, 255, 1) 0%, rgba(93, 214, 255, 0.7) 48%, rgba(93, 214, 255, 0) 100%);
}

.comet-one {
    animation: cometFly 14s linear infinite;
}

.comet-two {
    animation: cometFly 18s linear infinite;
    animation-delay: 5s;
}

.comet-three {
    animation: cometFly 22s linear infinite;
    animation-delay: 11s;
}

.dust-glow {
    width: 22vw;
    height: 22vw;
    border-radius: 50%;
    filter: blur(48px);
    opacity: 0.18;
    animation: glowFloat 20s ease-in-out infinite;
}

.dust-glow-one {
    top: 20%;
    left: 18%;
    background: radial-gradient(circle, rgba(93, 214, 255, 0.8), transparent 65%);
}

.dust-glow-two {
    right: 22%;
    bottom: 14%;
    background: radial-gradient(circle, rgba(121, 255, 177, 0.75), transparent 65%);
    animation-delay: -10s;
}

.error-stage {
    min-height: calc(100vh - var(--footer-height));
    display: grid;
    place-items: center;
    padding: 5vh 5vw calc(var(--footer-height) + 2vh);
}

.error-hero {
    text-align: center;
    max-width: 980px;
}

.error-kicker {
    margin: 0 0 1.25rem;
    letter-spacing: 0.44em;
    text-transform: uppercase;
    font-size: 0.8rem;
    font-weight: 700;
    color: rgba(255, 255, 255, 0.6);
}

.error-code {
    position: relative;
    margin: 0;
    font-size: clamp(9rem, 34vw, 28rem);
    line-height: 0.88;
    font-weight: 900;
    letter-spacing: -0.08em;
    color: #f8fdff;
    text-shadow:
        0 0 22px rgba(93, 214, 255, 0.32),
        0 0 80px rgba(93, 214, 255, 0.18),
        0 26px 120px rgba(0, 0, 0, 0.62);
    animation: codeFloat 10s ease-in-out infinite;
    will-change: transform;
}

.error-code::before,
.error-code::after {
    content: attr(data-text);
    position: absolute;
    inset: 0;
    pointer-events: none;
    opacity: 0.5;
}

.error-code::before {
    color: rgba(93, 214, 255, 0.38);
    transform: translate(-6px, 2px);
}

.error-code::after {
    color: rgba(255, 138, 91, 0.28);
    transform: translate(6px, -2px);
}

.error-subtitle {
    margin: 1rem auto 0;
    max-width: 560px;
    font-size: clamp(1rem, 1.8vw, 1.25rem);
    line-height: 1.7;
    color: var(--muted);
}

.footer-wrap {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    justify-content: center;
    padding: 0 1rem 1.25rem;
    pointer-events: none;
}

.footer-nav {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    padding: 0.8rem;
    border: 1px solid var(--line);
    border-radius: 999px;
    background: linear-gradient(180deg, rgba(10, 18, 42, 0.88), rgba(6, 10, 24, 0.76));
    backdrop-filter: blur(16px);
    box-shadow: var(--shadow);
    pointer-events: auto;
    flex-wrap: wrap;
}

.footer-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 46px;
    padding: 0.8rem 1.1rem;
    border-radius: 999px;
    border: 1px solid transparent;
    color: var(--ink);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 600;
    letter-spacing: 0.01em;
    transition: transform 0.3s ease, border-color 0.3s ease, background 0.3s ease, color 0.3s ease;
}

.footer-link:hover,
.footer-link:focus-visible {
    color: var(--ink);
    border-color: rgba(93, 214, 255, 0.45);
    background: rgba(93, 214, 255, 0.1);
    transform: translateY(-2px);
    outline: none;
}

.stellar-wave {
    width: 16px;
    height: 16px;
    margin-left: -8px;
    margin-top: -8px;
    border-radius: 50%;
    border: 1px solid rgba(255, 255, 255, 0.5);
    box-shadow: 0 0 18px rgba(93, 214, 255, 0.24);
    animation: waveExpand 1.6s ease-out forwards;
    pointer-events: none;
}

@keyframes drift {
    from { transform: translate3d(0, 0, 0); }
    to { transform: translate3d(-140px, 180px, 0); }
}

@keyframes pulseNebula {
    0%, 100% { transform: scale(1) translate3d(0, 0, 0); }
    50% { transform: scale(1.08) translate3d(3vw, -2vw, 0); }
}

@keyframes floatPlanet {
    0%, 100% { transform: translate3d(0, 0, 0); }
    50% { transform: translate3d(0, -18px, 0); }
}

@keyframes cometFly {
    0% {
        transform: translate3d(0, 0, 0) rotate(-24deg) scaleX(0.7);
        opacity: 0;
    }
    8% {
        opacity: 1;
    }
    62% {
        opacity: 0.95;
    }
    100% {
        transform: translate3d(140vw, 85vh, 0) rotate(-24deg) scaleX(1.08);
        opacity: 0;
    }
}

@keyframes glowFloat {
    0%, 100% { transform: translate3d(0, 0, 0) scale(1); }
    50% { transform: translate3d(24px, -18px, 0) scale(1.08); }
}

@keyframes codeFloat {
    0%, 100% { transform: translate3d(0, 0, 0); }
    50% { transform: translate3d(0, -10px, 0); }
}

@keyframes waveExpand {
    from {
        transform: scale(0.2);
        opacity: 0.86;
    }
    to {
        transform: scale(24);
        opacity: 0;
    }
}

@media (max-width: 991px) {
    :root {
        --footer-height: 132px;
    }

    .orbit-one {
        width: 110vw;
        height: 110vw;
    }

    .orbit-two {
        width: 82vw;
        height: 82vw;
    }

    .planet-one {
        top: 10%;
        right: 2%;
    }

    .planet-three {
        left: -14%;
        bottom: -6%;
    }
}

@media (max-width: 767px) {
    :root {
        --footer-height: 168px;
    }

    .error-stage {
        padding-top: 9vh;
        padding-left: 1.25rem;
        padding-right: 1.25rem;
    }

    .error-kicker {
        letter-spacing: 0.28em;
        font-size: 0.72rem;
    }

    .error-subtitle {
        max-width: 320px;
        font-size: 0.98rem;
    }

    .footer-nav {
        width: min(100%, 560px);
        border-radius: 28px;
    }

    .footer-link {
        flex: 1 1 calc(50% - 0.6rem);
    }

    .planet-two {
        left: 0;
        top: 12%;
    }

    .planet-four {
        right: 6%;
        bottom: 24%;
    }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}