:root {
    color-scheme: dark;
    --ink: #f4f7f8;
    --muted: #a6b1b6;
    --dim: #718087;
    --cyan: #16c1de;
    --cyan-bright: #75e8f7;
    --cyan-soft: rgba(22, 193, 222, .09);
    --night: #06090a;
    --deep: #020405;
    --panel: #0c1113;
    --panel-raised: #11181b;
    --line: rgba(224, 247, 250, .12);
    --line-strong: rgba(117, 232, 247, .28);
    --container: 1200px;
    --font-display: "Space Grotesk", "Segoe UI", sans-serif;
    --font-mono: "IBM Plex Mono", Consolas, monospace;
    --ease: cubic-bezier(.22, 1, .36, 1);
}

*, *::before, *::after { box-sizing: border-box; }

html {
    min-width: 320px;
    min-height: 100%;
    scroll-behavior: smooth;
    background: var(--deep);
}

body {
    display: flex;
    min-height: 100vh;
    margin: 0;
    overflow-x: hidden;
    flex-direction: column;
    background:
        radial-gradient(circle at 86% 7%, rgba(22, 193, 222, .09), transparent 28rem),
        linear-gradient(135deg, rgba(255,255,255,.025) 25%, transparent 25%) 0 0 / 8px 8px,
        var(--night);
    color: var(--ink);
    font: 400 1rem/1.65 var(--font-display);
    text-rendering: optimizeLegibility;
}

main { flex: 1; }

.page-grid {
    position: fixed;
    inset: 0;
    z-index: -1;
    pointer-events: none;
    background-image:
        linear-gradient(rgba(117, 232, 247, .035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(117, 232, 247, .035) 1px, transparent 1px);
    background-size: 72px 72px;
    -webkit-mask-image: linear-gradient(to bottom, #000, transparent 84%);
    mask-image: linear-gradient(to bottom, #000, transparent 84%);
}

::selection { background: var(--cyan); color: var(--deep); }
a { color: inherit; }
img { display: block; max-width: 100%; }
button { color: inherit; font: inherit; }
:focus-visible { outline: 2px solid var(--cyan-bright); outline-offset: 4px; }

.container {
    width: min(calc(100% - 3rem), var(--container));
    margin-inline: auto;
}

.skip-link {
    position: fixed;
    top: 1rem;
    left: 1rem;
    z-index: 100;
    padding: .7rem 1rem;
    background: var(--cyan);
    color: var(--deep);
    font-weight: 700;
    text-decoration: none;
    transform: translateY(-160%);
}

.skip-link:focus { transform: none; }

.site-header {
    position: relative;
    z-index: 20;
    height: 88px;
    flex: 0 0 auto;
    border-bottom: 1px solid var(--line);
    background: rgba(6, 9, 10, .78);
    backdrop-filter: blur(18px);
}

.header-inner,
.footer-inner {
    display: flex;
    height: 100%;
    align-items: center;
    justify-content: space-between;
    gap: 2rem;
}

.brand {
    display: inline-flex;
    width: 96px;
    height: 65px;
    align-items: center;
    text-decoration: none;
}

.brand img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.header-link {
    display: inline-flex;
    gap: .65rem;
    align-items: center;
    color: var(--muted);
    font-size: .82rem;
    text-decoration: none;
    transition: color .18s ease;
}

.header-link span,
.button-primary span,
.button-secondary span,
.text-link span {
    display: inline-block;
    transition: transform .2s var(--ease);
}

.header-link:hover { color: var(--ink); }
.header-link:hover span,
.button-primary:hover span,
.button-secondary:hover span,
.text-link:hover span { transform: translate(2px, -2px); }

h1, h2, h3, p { margin-top: 0; }
h1, h2, h3 { text-wrap: balance; }

.intro-hero {
    position: relative;
    display: grid;
    min-height: 690px;
    align-items: center;
    padding: clamp(4.5rem, 8vw, 7rem) 0;
}

.intro-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(22rem, .72fr);
    gap: clamp(3rem, 8vw, 8rem);
    align-items: center;
}

.intro-copy h1 {
    max-width: 10ch;
    margin-bottom: 2rem;
    font-size: clamp(4.2rem, 7vw, 7.1rem);
    font-weight: 600;
    letter-spacing: -.068em;
    line-height: .91;
}

.intro-copy h1 em { color: var(--cyan); font-style: normal; }

.intro-copy > p {
    max-width: 43rem;
    margin-bottom: 0;
    color: var(--muted);
    font-size: clamp(1.05rem, 1.6vw, 1.23rem);
}

.actions {
    display: flex;
    flex-wrap: wrap;
    gap: .75rem;
    margin-top: 2.25rem;
}

.button-primary,
.button-secondary {
    display: inline-flex;
    min-height: 3.4rem;
    align-items: center;
    justify-content: center;
    gap: .75rem;
    padding: .9rem 1.25rem;
    text-decoration: none;
    transition: transform .2s var(--ease), background .2s ease, color .2s ease, border-color .2s ease;
}

.button-primary {
    background: var(--cyan);
    color: #001013;
    font-weight: 600;
    clip-path: polygon(0 7px, 7px 0, 100% 0, 100% calc(100% - 7px), calc(100% - 7px) 100%, 0 100%);
}

.button-primary:hover { background: var(--cyan-bright); transform: translateY(-2px); }

.button-secondary {
    border: 1px solid var(--line-strong);
    background: rgba(8, 13, 15, .55);
    color: var(--muted);
}

.button-secondary:hover {
    border-color: var(--cyan);
    background: var(--cyan-soft);
    color: var(--ink);
    transform: translateY(-2px);
}

.explanation-card {
    position: relative;
    padding: clamp(2rem, 4vw, 3.25rem);
    border: 1px solid var(--line-strong);
    border-left: 3px solid var(--cyan);
    background:
        linear-gradient(110deg, rgba(22, 193, 222, .08), transparent 45%),
        rgba(8, 13, 15, .9);
    box-shadow: 0 35px 90px rgba(0,0,0,.34);
}

.explanation-card::after {
    content: "";
    position: absolute;
    top: -1px;
    right: -1px;
    width: 4.5rem;
    height: 1px;
    background: var(--cyan);
}

.card-label {
    margin-bottom: 1.4rem;
    color: var(--cyan-bright);
    font: 400 .66rem/1.4 var(--font-mono);
    letter-spacing: .08em;
    text-transform: uppercase;
}

.explanation-card h2 {
    max-width: 16ch;
    margin-bottom: 2rem;
    font-size: clamp(1.7rem, 2.8vw, 2.45rem);
    font-weight: 600;
    letter-spacing: -.04em;
    line-height: 1.08;
}

.explanation-card dl { margin: 0; }

.explanation-card dl > div {
    display: grid;
    grid-template-columns: minmax(7rem, .42fr) minmax(0, 1fr);
    gap: 1.25rem;
    padding: 1.1rem 0;
    border-top: 1px solid var(--line);
}

.explanation-card dt { font-size: .82rem; font-weight: 600; }
.explanation-card dd { margin: 0; color: var(--dim); font-size: .78rem; line-height: 1.55; }

.context-section {
    padding: clamp(5rem, 9vw, 8rem) 0;
    border-block: 1px solid var(--line);
    background: rgba(0,0,0,.3);
}

.context-grid {
    display: grid;
    grid-template-columns: minmax(0, .75fr) minmax(22rem, .8fr);
    gap: clamp(3rem, 10vw, 10rem);
    align-items: start;
}

.context-heading h2 {
    max-width: 14ch;
    margin-bottom: 0;
    font-size: clamp(2.7rem, 5vw, 5rem);
    font-weight: 600;
    letter-spacing: -.055em;
    line-height: .98;
}

.context-copy > p { color: var(--muted); font-size: 1.02rem; }
.context-copy > p + p { margin-top: 1.4rem; }

.contact-line {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 2rem;
    align-items: end;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid var(--line-strong);
}

.contact-line strong,
.contact-line span { display: block; }
.contact-line strong { margin-bottom: .3rem; }
.contact-line > div span { color: var(--dim); font-size: .78rem; }

.text-link {
    display: inline-flex;
    align-items: center;
    gap: .65rem;
    color: var(--cyan-bright);
    font-weight: 600;
    text-decoration: none;
    white-space: nowrap;
}

.text-link:hover { color: var(--ink); }

.site-footer {
    height: 76px;
    flex: 0 0 auto;
    border-top: 1px solid var(--line);
    background: var(--deep);
}

.footer-inner {
    color: var(--dim);
    font: 400 .62rem/1.4 var(--font-mono);
}

.error-main {
    display: grid;
    min-height: calc(100vh - 164px);
    align-items: center;
    padding: clamp(3rem, 7vw, 6rem) 0;
}

.error-panel {
    position: relative;
    max-width: 800px;
    margin-inline: auto;
    padding: clamp(2.5rem, 6vw, 5rem);
    border: 1px solid var(--line-strong);
    border-top: 3px solid var(--cyan);
    background:
        linear-gradient(110deg, rgba(22,193,222,.08), transparent 45%),
        rgba(8, 13, 15, .9);
    box-shadow: 0 35px 100px rgba(0,0,0,.36);
    text-align: center;
}

.error-number {
    margin-bottom: 1.6rem;
    color: var(--cyan);
    font: 500 .78rem/1 var(--font-mono);
    letter-spacing: .15em;
}

.error-panel h1 {
    margin-bottom: 1.5rem;
    font-size: clamp(3.4rem, 7vw, 6.2rem);
    font-weight: 600;
    letter-spacing: -.065em;
    line-height: .94;
}

.error-panel > p:not(.error-number):not(.redirect-note) {
    max-width: 39rem;
    margin-inline: auto;
    color: var(--muted);
    font-size: 1.05rem;
}

.error-actions {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: .75rem;
    margin-top: 2.2rem;
}

.redirect-note {
    margin: 2rem 0 0;
    color: var(--dim);
    font: 400 .65rem/1.7 var(--font-mono);
}

.redirect-note strong { color: var(--cyan-bright); }

.redirect-note button {
    padding: 0;
    border: 0;
    border-bottom: 1px solid var(--dim);
    background: transparent;
    color: var(--muted);
    cursor: pointer;
}

.redirect-note button:hover { color: var(--ink); }

html.js [data-reveal] {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity .7s var(--ease), transform .7s var(--ease);
}

html.js [data-reveal].is-visible { opacity: 1; transform: none; }

@media (max-width: 900px) {
    .intro-grid,
    .context-grid { grid-template-columns: 1fr; }

    .intro-hero { min-height: 0; }
    .intro-copy { max-width: 48rem; }
    .explanation-card { max-width: 45rem; }
    .context-grid { gap: 2.5rem; }
    .context-heading h2 { max-width: 16ch; }
}

@media (max-width: 620px) {
    .container { width: min(calc(100% - 2rem), var(--container)); }
    .site-header { height: 74px; }
    .brand { width: 78px; height: 56px; }
    .header-link { font-size: .7rem; }
    .intro-hero { padding: 4.5rem 0; }
    .intro-copy h1 { font-size: clamp(3.5rem, 16vw, 5.1rem); }
    .actions { display: grid; }
    .button-primary, .button-secondary { width: 100%; }
    .explanation-card { padding: 1.6rem; }
    .explanation-card dl > div { grid-template-columns: 1fr; gap: .3rem; }
    .contact-line { grid-template-columns: 1fr; gap: 1.2rem; }
    .error-main { min-height: calc(100vh - 150px); }
    .error-panel { padding: 2rem 1.25rem; }
    .error-actions { display: grid; }
    .footer-inner { align-items: flex-start; flex-direction: column; justify-content: center; gap: .25rem; }
}

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