.tail-container * {
            font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
        }

        /* Color treatment from satellite-hunter-reference-v1 */
        /* Viewport-fixed hero — same look on short and long pages */
        .hero-bg {
            background: linear-gradient(135deg, #0f172a 0%, #1e40af 100%);
            background-attachment: fixed;
            position: relative;
            min-height: 100vh;
        }

        .hero-bg::before {
            content: '';
            position: fixed;
            inset: 0;
            z-index: 0;
            background: radial-gradient(circle at 30% 70%, rgba(14, 165, 233, 0.15) 0%, transparent 50%);
            pointer-events: none;
        }

        .form-card {
            box-shadow: 0 25px 50px -12px rgb(14 165 233 / 0.25);
        }

        /* Site chrome — readable brand + scalable menu (not pills) */
        #site-chrome {
            position: relative;
            z-index: 20;
            margin-bottom: 1.25rem;
        }

        .site-chrome-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 1rem;
            padding: 0.75rem 0;
        }

        .brand {
            display: flex;
            align-items: center;
            gap: 0.85rem;
            min-width: 0;
            text-decoration: none;
            color: inherit;
        }

        .brand img {
            height: 52px;
            width: auto;
            flex-shrink: 0;
            filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.35));
        }

        .brand-text {
            display: flex;
            flex-direction: column;
            gap: 0.15rem;
            min-width: 0;
        }

        .brand-name {
            font-size: 1.15rem;
            font-weight: 600;
            color: #f8fafc;
            letter-spacing: -0.02em;
            line-height: 1.2;
        }

        .brand-sub {
            font-size: 0.8rem;
            font-weight: 500;
            color: #7dd3fc;
            line-height: 1.2;
        }

        /* Site menu + menu-toggle styles: theme.css (tool-v1 refined panel) */


        /*
         * TLE select panel — stands out from the soft Line 1/2 panels.
         * Outer shell is taller; textarea is only as tall as the two lines and
         * is vertically centered with flex (top-to-bottom, not side-to-side).
         */
        .tle-panel {
            display: flex;
            align-items: center;
            justify-content: center;
            min-height: 6.25rem;
            padding: 0.75rem 1rem;
            border-radius: 1rem;
            border: 2px solid #38bdf8;
            background:
                linear-gradient(180deg, rgba(14, 165, 233, 0.12) 0%, transparent 40%),
                #0f172a;
            box-shadow:
                inset 0 1px 0 rgba(125, 211, 252, 0.2),
                0 0 0 1px rgba(14, 165, 233, 0.15),
                0 12px 28px -12px rgba(14, 165, 233, 0.45);
        }

        #tleInput {
            width: 100%;
            height: auto;
            min-height: 0;
            box-sizing: border-box;
            resize: none;
            cursor: crosshair;
            font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
            font-size: 0.95rem;
            line-height: 1.55;
            padding: 0.15rem 0.25rem;
            border: none;
            border-radius: 0;
            background: transparent;
            color: #4ade80;
            outline: none;
            text-align: center;
            white-space: pre;
            overflow-x: auto;
            field-sizing: content; /* modern browsers: height follows content */
        }

        /* Fallback two-line height when field-sizing unsupported */
        @supports not (field-sizing: content) {
            #tleInput {
                height: 3.1rem;
            }
        }

        .tle-panel:focus-within {
            border-color: #7dd3fc;
            box-shadow:
                inset 0 1px 0 rgba(125, 211, 252, 0.25),
                0 0 0 3px rgba(14, 165, 233, 0.3),
                0 12px 28px -12px rgba(14, 165, 233, 0.5);
        }

        .data-row {
            display: flex;
            justify-content: space-between;
            gap: 0.75rem;
            padding: 0.45rem 0.35rem;
            border-radius: 0.5rem;
            font-size: 0.85rem;
            cursor: pointer;
            border-bottom: 1px solid #f4f4f5;
            transition: background 0.15s ease;
        }

        .data-row:last-child { border-bottom: none; }
        .data-row:hover { background: #f0f9ff; }

        .data-row.is-selected {
            background: #e0f2fe;
        }

        .data-row .label {
            color: #52525b;
            text-decoration: underline dotted;
            text-underline-offset: 2px;
        }

        .data-row .value {
            color: #0369a1;
            font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
            font-weight: 600;
            white-space: nowrap;
        }

        /* Match Catalog Readiness soft panels — no left accent stripe */
        .line-section {
            background: #fafafa;
            border: 1px solid #f4f4f5;
            border-radius: 1rem;
            padding: 1rem 1.1rem;
        }

        .line-header {
            color: #18181b;
            font-weight: 600;
            font-size: 0.9rem;
            margin-bottom: 0.65rem;
            padding-bottom: 0.45rem;
            border-bottom: 1px solid #e4e4e7;
        }

        #info-panel { min-height: 5.5rem; }

        .deep-dive-btn {
            display: inline-block;
            margin-top: 0.5rem;
            color: #0369a1;
            text-decoration: none;
            font-weight: 600;
            font-size: 0.8rem;
            border: 1px solid #0ea5e9;
            padding: 0.25rem 0.6rem;
            border-radius: 0.5rem;
            transition: background 0.15s ease, color 0.15s ease;
        }

        .deep-dive-btn:hover {
            background: #0ea5e9;
            color: #fff;
        }

        /* Collapsible intro — compact when closed; hint sits to the right of the title */
        .intro-card {
            margin-bottom: 1rem;
            padding: 0.65rem 1rem !important;
        }

        .intro-card[open] {
            padding: 1rem 1.25rem !important;
        }

        .intro-card summary {
            list-style: none;
            cursor: pointer;
            display: flex;
            align-items: center;
            gap: 0.75rem;
            user-select: none;
            min-height: 1.75rem;
        }

        .intro-card summary::-webkit-details-marker { display: none; }

        .intro-card summary .intro-title {
            font-size: 0.95rem;
            font-weight: 600;
            color: var(--sh-heading, #18181b);
            flex: 1 1 auto;
            min-width: 0;
            line-height: 1.3;
        }

        .intro-card summary .intro-hint {
            flex: 0 1 auto;
            font-size: 0.75rem;
            color: var(--sh-muted-2, #71717a);
            white-space: nowrap;
            text-align: right;
        }

        .intro-card summary .chevron {
            flex-shrink: 0;
            width: 1.35rem;
            height: 1.35rem;
            border-radius: 0.35rem;
            background: var(--sh-chevron-bg, #f4f4f5);
            color: var(--sh-chevron-fg, #52525b);
            display: inline-flex;
            align-items: center;
            justify-content: center;
            font-size: 0.7rem;
            transition: transform 0.15s ease, background 0.15s ease;
        }

        .intro-card[open] summary .chevron {
            transform: rotate(180deg);
            background: var(--sh-chevron-open-bg, #e0f2fe);
            color: var(--sh-chevron-open-fg, #0369a1);
        }

        /* On narrow screens, keep title + chevron; hide long hint if needed */
        @media (max-width: 520px) {
            .intro-card summary .intro-hint {
                display: none;
            }
        }

        .intro-card .intro-body {
            margin-top: 0.85rem;
            padding-top: 0.85rem;
            border-top: 1px solid var(--sh-border, #f4f4f5);
        }