/* Theme toggle button */
        .theme-toggle {
            position: absolute;
            top: 1.1rem;
            right: 1.5rem;
            background: rgba(255,255,255,0.1);
            border: 1.5px solid rgba(201,168,76,0.4);
            color: white;
            border-radius: 999px;
            padding: 0.3rem 0.85rem;
            font-size: 0.78rem;
            font-weight: 600;
            cursor: pointer;
            display: flex;
            align-items: center;
            gap: 0.4rem;
            transition: background 0.2s, border-color 0.2s;
            z-index: 10;
        }
        .theme-toggle:hover { background: rgba(255,255,255,0.18); border-color: var(--gold-lt); }

        * { box-sizing: border-box; margin: 0; padding: 0; }
        body {
            font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
            background: var(--bg);
            color: var(--text);
            background-image:
                radial-gradient(circle at 15% 50%, rgba(4,138,129,0.04) 0%, transparent 50%),
                radial-gradient(circle at 85% 20%, rgba(46,64,87,0.05) 0%, transparent 50%);
        }

        header {
            background: linear-gradient(135deg, #1a2a3e 0%, var(--primary) 50%, #1e3a4a 100%);
            color: white;
            padding: 2rem 2rem 0;
            position: relative;
            overflow: hidden;
        }
        header::before {
            content: '';
            position: absolute;
            inset: 0;
            background-image:
                radial-gradient(ellipse at 80% 50%, rgba(201,168,76,0.08) 0%, transparent 60%),
                repeating-linear-gradient(45deg, transparent, transparent 60px, rgba(255,255,255,0.01) 60px, rgba(255,255,255,0.01) 61px);
            pointer-events: none;
        }
        .header-inner {
            max-width: 1100px;
            margin: 0 auto;
            padding: 0 1rem 1.75rem;
            position: relative;
            display: flex;
            align-items: center;
            gap: 1.25rem;
        }
        .header-skull {
            font-size: 2.8rem;
            line-height: 1;
            filter: drop-shadow(0 0 12px rgba(201,168,76,0.5));
            flex-shrink: 0;
        }
        .header-text h1 {
            font-family: 'Cinzel', serif;
            font-size: 1.65rem;
            font-weight: 800;
            letter-spacing: 0.04em;
            background: linear-gradient(90deg, #ffffff 0%, var(--gold-lt) 60%, #ffffff 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            line-height: 1.2;
        }
        .header-text p {
            font-size: 0.8rem;
            opacity: 0.65;
            margin-top: 0.3rem;
            letter-spacing: 0.06em;
            text-transform: uppercase;
        }
        .header-divider {
            width: 100%;
            line-height: 0;
            display: block;
        }
        .header-divider svg { display: block; width: 100%; }

        .container { max-width: 1100px; margin: 1.5rem auto; padding: 0 1rem; }

        #progress { display: none; }
        .progress-bar-wrap { background: var(--border); border-radius: 999px; height: 6px; margin-top: 0.75rem; overflow: hidden; }
        .progress-bar { height: 6px; border-radius: 999px; background: linear-gradient(90deg, var(--accent), #2E9E8F); transition: width 0.4s ease; }
        #progressText { font-size: 0.85rem; color: var(--muted); }

        #results { display: none; }

        .row-flex { display: flex; justify-content: space-between; align-items: center; margin-bottom: 1.25rem; }
        .row-flex h2 { margin-bottom: 0; }

        .error-box { background: #fff5f5; border: 1.5px solid #ffcccc; color: #c0392b; padding: 1.1rem 1.25rem; border-radius: 8px; font-size: 0.88rem; line-height: 1.6; margin-bottom: 1.5rem; }
        .error-box code { background: #ffe8e8; padding: 0.15rem 0.4rem; border-radius: 4px; font-size: 0.82rem; }

        details summary { cursor: pointer; font-size: 0.82rem; color: var(--accent); font-weight: 600; padding: 0.5rem 0; }
        details summary:hover { text-decoration: underline; }
        details > .details-body { margin-top: 0.5rem; }

        .step { margin-bottom: 1.1rem; }
        .step:last-child { margin-bottom: 0; }
        hr { border: none; border-top: 1px solid var(--border); margin: 1.25rem 0; }

        .hint { font-size: 0.78rem; color: var(--muted); margin-top: 0.4rem; }
        .hint code { background: #f0f0f0; padding: 0.1rem 0.35rem; border-radius: 3px; font-size: 0.78rem; }

        .cache-bar { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 0.5rem;
            background: var(--bg); border: 1px solid var(--border); border-radius: 7px;
            padding: 0.6rem 0.9rem; font-size: 0.82rem; color: var(--muted); }
        .cache-bar strong { color: var(--text); }
        .cache-bar.has-cache { border-color: var(--accent); background: #f0faf9; }
        .cache-actions { display: flex; gap: 0.4rem; }
        .btn-danger { background: transparent; border: 1.5px solid var(--loss); color: var(--loss); }
        .btn-danger:hover { background: var(--loss); color: white; }

        /* PDF toolbar */
        .pdf-toolbar { display: flex; justify-content: flex-end; margin-bottom: 1rem; }

        /* ── Tab Navigation ─────────────────────────────────────────────── */
        .tab-nav {
            display: flex;
            gap: 0;
            margin-bottom: 1.5rem;
            border-bottom: 2px solid var(--border);
        }
        .tab-btn {
            padding: 0.65rem 1.6rem;
            border: none;
            background: none;
            font-family: 'Cinzel', serif;
            font-size: 0.8rem;
            letter-spacing: 0.07em;
            color: var(--muted);
            cursor: pointer;
            border-bottom: 3px solid transparent;
            margin-bottom: -2px;
            transition: color 0.2s, border-color 0.2s;
            display: flex;
            align-items: center;
            gap: 0.4rem;
        }
        .tab-btn.active { color: var(--gold); border-bottom-color: var(--gold); font-weight: 700; }
        .tab-btn:hover:not(.active) { color: var(--text); border-bottom-color: var(--border); }