/* Vẽ tranh, vẽ ô vuông (/cong-cu/ve-tranh): iframe bảng vẽ phủ kín cửa sổ. Tệp nạp ở mọi trang → lớp có tiền tố vtr-. */
.chinh:has(> .vtr) { padding: 0; }
.vtr { position: fixed; inset: 0; z-index: 10; display: flex; flex-direction: column; background: #fff; color: var(--chu); }
.vtr-thanh { flex: none; display: flex; align-items: center; gap: 10px; min-height: 52px; padding: 6px 12px; background: var(--c-dam); color: #fff; }
.che-do-chieu .vtr-thanh .vtr-lk { color: #fff; border-color: rgba(255,255,255,.55); }
.che-do-chieu .vtr-thanh .vtr-lk:hover { background: rgba(255,255,255,.12); color: #fff; }
.vtr-chon { display: flex; flex: none; border: 1px solid rgba(255,255,255,.55); border-radius: 999px; padding: 2px; }
.vtr-chon__o { color: #fff; text-decoration: none; font-weight: 600; font-size: .875rem; padding: 5px 14px; border-radius: 999px; white-space: nowrap; }
.vtr-chon__o:hover { background: rgba(255,255,255,.12); }
.vtr-chon__o[aria-current="page"] { background: #fff; color: var(--c-dam); }
.vtr-ghi { margin: 0; flex: 1; min-width: 0; font-size: .8125rem; color: #d9e3f2; }
.vtr-toan { background: var(--nhan); border-color: var(--nhan); color: var(--c-dam); }
.vtr-toan:hover { background: #f5cf7f; border-color: #f5cf7f; color: var(--c-dam); }
.vtr-khung { flex: 1; width: 100%; border: 0; display: block; background: #fff; }
@media (max-width: 900px) {
  .vtr-ghi { display: none; }
  .vtr-chon { margin-left: auto; }
}
@media (max-width: 560px) {
  .vtr-thanh { gap: 6px; padding: 6px 8px; flex-wrap: wrap; }
  .vtr-toan { display: none; }
  .vtr-chon__o { padding: 5px 10px; }
}