.hero-shell {
            position: relative;
            overflow: hidden;
            border: 1px solid var(--line);
            border-radius: 28px;
            background:
                linear-gradient(180deg, rgba(255,255,255,0.98), rgba(247,244,239,0.98)),
                radial-gradient(circle at 88% 16%, rgba(246,163,24,0.14), transparent 20%),
                radial-gradient(circle at 18% 82%, rgba(40,148,227,0.16), transparent 20%);
            box-shadow: var(--shadow-soft);
        }
        .fade-in {
            animation: fadeIn 0.45s ease-out;
        }
        .about-pillar-button--active {
            background: rgba(22, 49, 74, 0.88);
            color: rgba(255, 255, 255, 0.96);
        }
        html[data-theme-key="sombre"] .hero-shell {
            border-color: color-mix(in srgb, var(--line) 78%, transparent);
            background:
                linear-gradient(180deg, color-mix(in srgb, var(--surface) 90%, #020617), color-mix(in srgb, var(--paper) 95%, #020617)),
                radial-gradient(circle at 88% 16%, color-mix(in srgb, var(--accent-tertiary) 14%, transparent), transparent 22%),
                radial-gradient(circle at 18% 82%, color-mix(in srgb, var(--accent-secondary) 16%, transparent), transparent 22%);
            box-shadow: 0 18px 36px rgba(0, 0, 0, 0.34);
        }
        html[data-theme-key="sombre"] blockquote {
            border-color: color-mix(in srgb, var(--line) 76%, transparent);
            background: color-mix(in srgb, var(--surface) 84%, #020617);
            color: color-mix(in srgb, var(--heading-muted, var(--muted)) 88%, #ffffff);
        }
        html[data-theme-key="sombre"] .about-pillar-button--active {
            background: linear-gradient(135deg, var(--accent-secondary), var(--accent-primary));
            color: var(--cta-on-accent, #ffffff);
            border-color: transparent;
        }
        @keyframes fadeIn {
            from {
                opacity: 0;
                transform: translateY(8px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }