.background-tool{max-width:640px;margin:0 auto;display:flex;flex-direction:column;gap:16px}.background-tool .drop-zone{border:2px dashed rgba(255,255,255,.25);border-radius:14px;padding:40px 20px;text-align:center;transition:border-color .2s ease,background .2s ease}.background-tool .drop-zone.is-dragover{border-color:#f298d4cc;background:#f298d414}.background-tool .drop-title{font-size:1.05rem;margin:0 0 6px}.background-tool .drop-hint{opacity:.6;font-size:.85rem;margin:0 0 16px}.background-tool .bg-btn{font-family:inherit;cursor:pointer;border:none;border-radius:10px;padding:12px 22px;font-size:.95rem;font-weight:600;transition:transform .12s ease,opacity .2s ease,background .2s ease}.background-tool .bg-btn:active{transform:translateY(1px)}.background-tool .bg-btn:disabled{opacity:.4;cursor:not-allowed}.background-tool .bg-btn-primary{background:#ffffff1f;color:#fff}.background-tool .bg-btn-generate{background:var(--surface-raised);border:1px solid var(--border-strong);color:var(--text);box-shadow:0 1px #ffffff0f inset}.background-tool .bg-btn-generate:hover:not(:disabled){background:#222226;border-color:#fff3}.background-tool .file-info{text-align:center;font-size:.9rem;opacity:.85;margin:0}.background-tool .frame-warn{text-align:center;font-size:.85rem;color:#f2c98d;margin:0}.background-tool .bg-status{text-align:center;font-size:.95rem;margin:0}.background-tool .bg-error{text-align:center;font-size:.9rem;color:#ff8d8d;background:#ff8d8d1a;border-radius:10px;padding:10px 14px;margin:0}