.fcv-letter-wrap{max-width:1240px;margin:0 auto;padding:0 16px}.fcv-intake{max-width:760px;margin:0 auto}.fcv-letter-host{position:relative;height:min(920px,calc(100dvh - 72px));min-height:640px;border:1px solid var(--card-border,#e6e4f2);border-radius:18px;overflow:hidden;background:#fff;box-shadow:0 18px 40px -28px rgba(30,27,58,.35)}.fcv-letter-frame,.fcv-letter-frame>.bld-split{height:100%}.fcv-letter-toggle{display:none;gap:8px;margin:0 0 10px}.fcv-letter-toggle button{flex:1;padding:10px 12px;border-radius:10px;font:inherit;font-weight:600;font-size:14px;border:1px solid #e4e4ef;background:#fff;color:#374151;cursor:pointer}.fcv-letter-toggle button.active{background:#6366f1;border-color:#6366f1;color:#fff}@media (max-width:900px){.fcv-letter-toggle{display:flex}.fcv-letter-host{height:calc(100dvh - 130px);min-height:560px;border-radius:14px}.fcv-letter-wrap{padding:0 10px}}[data-theme=dark] .fcv-letter-host{background:#18181b;border-color:#2b2940}[data-theme=dark] .fcv-letter-toggle button{background:#1c1b2a;border-color:#2b2940;color:#d4d1e6}[data-theme=dark] .fcv-letter-toggle button.active{background:#6366f1;color:#fff}