.mwb{border:2px solid #89cbd1;border-radius:22px;background:linear-gradient(145deg,#effbff,#fffaf0);padding:24px;color:#163947;min-width:0}.mwb h3{font-size:1.45rem;margin:0 0 10px}.mwb p{line-height:1.6}.mwb fieldset{min-width:0;margin:24px 0;border:1px solid #accbd2;border-radius:16px;padding:18px;background:#fff}.mwb legend{font-weight:800;padding:0 8px;max-width:100%;line-height:1.5}.mwb-row{padding:12px 0;border-bottom:1px solid #e3edef}.mwb-row:last-child{border-bottom:0}.mwb label{display:grid;grid-template-columns:minmax(0,1fr) minmax(110px,160px);align-items:center;gap:14px;font-weight:700;line-height:1.5}.mwb input{box-sizing:border-box;width:100%;min-height:50px;font:700 1.15rem system-ui;border:2px solid #89acba;border-radius:12px;padding:10px;background:#f6fcff;color:#12394b}.mwb input[aria-invalid=true]{border-color:#a74018;background:#fff7ed}.mwb-feedback{font-size:.96rem;margin:8px 0 0;white-space:normal}.mwb-feedback:empty{display:none}.mwb-feedback[data-status=correct]{color:#176244}.mwb-feedback[data-status=incorrect],.mwb-feedback[data-status=format],.mwb-feedback[data-status=missing]{color:#8b3519}.mwb button{font:800 1.05rem system-ui;border:0;border-radius:14px;background:linear-gradient(130deg,#075b88,#067e84);color:#fff;min-height:54px;padding:15px 22px;box-shadow:0 5px 15px #176c8030;cursor:pointer;line-height:1.5}.mwb button:hover{background:#055c72}.mwb input:focus-visible,.mwb button:focus-visible,.mwb-summary:focus-visible{outline:3px solid #ae6812;outline-offset:4px}.mwb-summary:not(:empty){padding:18px;margin:18px 0;background:#ecf7f4;border-left:5px solid #25846a;border-radius:10px}.mwb-note{font-size:.9rem;color:#455e68}.mwb-summary p{margin:8px 0 0}@media(max-width:560px){.mwb{padding:15px;border-radius:16px}.mwb fieldset{padding:12px}.mwb label{grid-template-columns:1fr;gap:8px}.mwb input{max-width:220px}.mwb button{width:100%}}

/* Practice79: all answers remain in the DOM; only the selected problem is visible. */
.mwb [data-mwb-group][hidden]{display:none!important}
.mwb-nav{margin:20px 0;padding:16px;border:1px solid #94c9cf;border-radius:16px;background:#e3f4f5}
.mwb-nav .mwb-page{margin:0 0 12px;color:#075b70;font-size:1.1rem}
.mwb-nav label{grid-template-columns:1fr;gap:8px}
.mwb-nav select{box-sizing:border-box;width:100%;min-width:0;max-width:100%;min-height:50px;padding:10px;border:2px solid #89acba;border-radius:12px;background:#fff;color:#163947;font:700 1rem system-ui}
.mwb-nav-buttons{display:flex;gap:12px;flex-wrap:wrap;margin-top:14px}
.mwb-nav-buttons button{flex:1;min-width:130px;min-height:48px;padding:10px 15px}
.mwb-nav button:disabled{opacity:.5;cursor:default;box-shadow:none}
.mwb-nav select:focus-visible,.mwb [data-mwb-group]:focus-visible{outline:3px solid #ae6812;outline-offset:4px}
@media(max-width:560px){.mwb-nav{padding:12px}.mwb-nav-buttons button{width:auto}}