/* SIGNAL hub — landing page for the standalone playground */

:root {
    --bg:        #0c0a08;
    --bg-2:      #15110c;
    --ink:       #f3e8d6;
    --ink-dim:   #b9a489;
    --amber:     #e8a23d;
    --amber-dim: #c9821f;
    --line:      rgba(232, 162, 61, 0.16);
    --card-bg:   rgba(28, 22, 16, 0.72);
}

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

html, body { height: 100%; }

body {
    font-family: "SF Mono", "Segoe UI Mono", "Roboto Mono", ui-monospace, monospace;
    background: var(--bg);
    color: var(--ink);
    min-height: 100dvh;
    display: grid;
    place-items: center;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

/* ── Background layers ─────────────────────────────────────────────── */
.hub-bg { position: fixed; inset: 0; z-index: 0; pointer-events: none; }

.hub-grid {
    position: absolute; inset: -2px;
    background-image:
        linear-gradient(var(--line) 1px, transparent 1px),
        linear-gradient(90deg, var(--line) 1px, transparent 1px);
    background-size: 46px 46px;
    mask-image: radial-gradient(ellipse 80% 70% at 50% 40%, #000 30%, transparent 78%);
}

.hub-glow {
    position: absolute; inset: 0;
    background:
        radial-gradient(60% 50% at 50% 8%, rgba(232,162,61,0.16), transparent 70%),
        radial-gradient(50% 40% at 80% 90%, rgba(232,162,61,0.08), transparent 70%);
}

.hub-noise {
    position: absolute; inset: 0; opacity: 0.05;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ── Layout ────────────────────────────────────────────────────────── */
.hub {
    position: relative; z-index: 1;
    width: min(880px, 92vw);
    padding: 56px 0 40px;
    text-align: center;
}

.hub-head { margin-bottom: 44px; }

.hub-kicker {
    font-size: 11px; letter-spacing: 0.42em; color: var(--amber);
    margin-bottom: 18px; opacity: 0.85;
}

.hub-title {
    font-size: clamp(48px, 11vw, 96px);
    font-weight: 800; letter-spacing: 0.08em; line-height: 1;
    color: var(--ink);
    text-shadow: 0 0 38px rgba(232, 162, 61, 0.28);
}

.hub-sub {
    margin-top: 16px; font-size: 14px; letter-spacing: 0.06em;
    color: var(--ink-dim);
}

/* ── Cards ─────────────────────────────────────────────────────────── */
.hub-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

@media (max-width: 640px) {
    .hub-cards { grid-template-columns: 1fr; }
}

.card {
    position: relative;
    display: flex; flex-direction: column; align-items: flex-start;
    gap: 18px;
    text-align: left; text-decoration: none; color: inherit;
    padding: 26px 24px 22px;
    background: var(--card-bg);
    border: 1px solid var(--line);
    border-radius: 16px;
    backdrop-filter: blur(8px);
    overflow: hidden;
    transition: transform 0.22s ease, border-color 0.22s ease, box-shadow 0.22s ease;
}

.card::before {
    content: ""; position: absolute; inset: 0;
    background: radial-gradient(120% 80% at 0% 0%, rgba(232,162,61,0.10), transparent 60%);
    opacity: 0; transition: opacity 0.22s ease;
}

.card:hover {
    transform: translateY(-4px);
    border-color: rgba(232, 162, 61, 0.5);
    box-shadow: 0 18px 50px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(232,162,61,0.18) inset;
}
.card:hover::before { opacity: 1; }

.card__media {
    color: var(--amber);
    width: 72px; height: 72px;
    display: grid; place-items: center;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: rgba(0,0,0,0.25);
}

.card__body { flex: 1; }

.card__tag {
    font-size: 10px; letter-spacing: 0.22em; color: var(--amber-dim);
    margin-bottom: 8px;
}

.card__title {
    font-size: 20px; font-weight: 700; letter-spacing: 0.05em;
    margin-bottom: 8px;
}

.card__desc {
    font-size: 13px; line-height: 1.55; color: var(--ink-dim);
}

.card__cta {
    font-size: 12px; letter-spacing: 0.16em; color: var(--amber);
    margin-top: 2px;
}

/* ── Footer ────────────────────────────────────────────────────────── */
.hub-foot {
    margin-top: 36px; font-size: 11px; letter-spacing: 0.14em;
    color: var(--ink-dim); opacity: 0.7;
    display: inline-flex; align-items: center; gap: 8px;
}
.hub-foot__dot {
    width: 7px; height: 7px; border-radius: 50%;
    background: var(--amber);
    box-shadow: 0 0 10px var(--amber);
    animation: pulse 2.4s ease-in-out infinite;
}
@keyframes pulse { 0%,100% { opacity: 0.4; } 50% { opacity: 1; } }

/* ── Floating music launcher (the music icon) ──────────────────────── */
.music-fab {
    position: fixed; top: 20px; right: 20px; z-index: 5;
    display: inline-flex; align-items: center; gap: 9px;
    padding: 10px 16px 10px 13px;
    color: var(--bg);
    background: var(--amber);
    border-radius: 999px;
    text-decoration: none;
    font-size: 12px; font-weight: 700; letter-spacing: 0.16em;
    box-shadow: 0 8px 26px rgba(232, 162, 61, 0.35);
    transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}
.music-fab:hover {
    transform: translateY(-2px);
    background: #f2b557;
    box-shadow: 0 12px 32px rgba(232, 162, 61, 0.5);
}
.music-fab svg { display: block; }
@media (max-width: 480px) {
    .music-fab__label { display: none; }
    .music-fab { padding: 11px; }
}