.mast { display: flex; align-items: center; justify-content: space-between; gap: 28px; padding-block: 28px 26px; }
.brand { display: flex; align-items: center; gap: 16px; color: var(--ink); text-decoration: none; min-height: 52px; font: 27px/1.1 var(--book); }
.sub { display: block; font: 16px/1.6 var(--sans); color: var(--muted); margin-top: 3px; }
.mark { display: block; width: 34px; height: 44px; border: 8px solid var(--blue); border-bottom: 0; border-radius: 24px 24px 0 0; position: relative; }
.mark::after { content: ""; width: 17px; height: 17px; border-radius: 50%; background: var(--gold); position: absolute; bottom: 0; left: 20px; }
.chap-link { display: inline-flex; min-height: 48px; align-items: center; gap: 20px; font: 17px/1.4 var(--sans); }
.tabs { display: flex; gap: 5px; border-bottom: 2px solid var(--blue); }
.tab { display: flex; justify-content: center; align-items: center; min-height: 59px; flex: 1; padding: 12px 15px; border-radius: 18px 18px 0 0; background: #f0f2f0; text-decoration: none; text-align: center; font: 17px/1.4 var(--sans); }
.tab:hover { background: #d8e7ee; text-decoration: underline; }
.tab.on { background: var(--sky); color: var(--ink); }
.foot { background: var(--soft); padding: 42px 0 36px; margin-top: 90px; }
.foot-top { display: flex; justify-content: space-between; align-items: center; gap: 28px; margin-bottom: 18px; }
.foot-name { font-size: 28px; }
.foot nav { display: flex; flex-wrap: wrap; gap: 8px 28px; }
.foot-link { font: 17px/1.45 var(--sans); padding-block: 9px; gap: 12px; }
.foot .w > p { max-width: 75ch; font: 17px/1.65 var(--sans); }
@media (max-width: 900px) {
  .tab { font-size: 16px; padding-inline: 9px; }
  .foot-top { align-items: flex-start; flex-direction: column; gap: 10px; }
}
@media (max-width: 680px) {
  .mast { gap: 16px; padding-block: 22px; align-items: flex-start; }
  .brand { font-size: 25px; gap: 11px; }
  .mark { width: 28px; height: 38px; border-width: 7px; margin-right: 4px; }
  .mark::after { width: 14px; height: 14px; left: 15px; }
  .chap-link { max-width: 104px; font-size: 16px; gap: 8px; }
  .tabs { flex-wrap: wrap; gap: 5px; padding-bottom: 5px; }
  .tab { flex: 1 1 45%; min-height: 48px; padding: 10px; border-radius: 13px; }
  .tab:last-child { flex-basis: 100%; }
  .foot { padding-block: 30px; margin-top: 56px; }
  .foot nav { display: grid; gap: 3px; }
  .foot-link { min-height: 48px; font-size: 17px; }
}