/* ===== Код Хэмминга: стили ===== */

:root {
  --bg:        #f8f8f8;
  --ink:       #444;
  --ink-soft:  #535353;
  --ink-faint: #979797;
  --banner:    #2052bb;
  --line:      #eaeaea;
  --parity:    #2968ff;   /* контрольные биты   */
  --parity-bg: rgba(41, 104, 255, .10);
  --err:       #ff4343;   /* ошибка             */
  --err-bg:    rgba(255, 67, 67, .12);
  --ok:        #1e9e63;   /* исправленный бит   */
  --ok-bg:     rgba(30, 158, 99, .10);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "IBM Plex Sans", -apple-system, "Segoe UI", sans-serif;
  font-size: 1.05rem;
  line-height: 1.6;
}

.mono, code, .bit, td, th { font-family: "Inconsolata", Menlo, Consolas, monospace; }

.wrap { max-width: 44rem; margin: 0 auto; padding: 0 3rem; }

/* ---------- Шапка ---------- */
.banner {
  background: var(--banner);
  color: #f8f8f8;
  padding: 3.2rem 0 2.6rem;
}
.banner .kicker {
  font-size: .8rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  opacity: .75;
  margin-bottom: .6rem;
}
.banner h1 {
  font-family: "Inter", "IBM Plex Sans", sans-serif;
  font-weight: 800;
  font-size: 2.4rem;
  margin: 0 0 .8rem;
  line-height: 1.15;
}
.banner .lead { margin: 0; max-width: 36rem; opacity: .92; }

/* ---------- Шаги ---------- */
.step { padding: 2.6rem 0 1.2rem; border-bottom: 1px solid var(--line); }
.step h2 {
  font-family: "Inter", "IBM Plex Sans", sans-serif;
  font-weight: 600;
  font-size: 1.5rem;
  color: var(--ink-soft);
  display: flex;
  align-items: center;
  gap: .7rem;
  margin: 0 0 1rem;
}
.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.9rem; height: 1.9rem;
  border: 2px solid var(--banner);
  color: var(--banner);
  border-radius: 50%;
  font-size: 1rem;
  flex: none;
}
.step.locked { opacity: .38; pointer-events: none; filter: saturate(.4); }
.step.locked::after {
  content: "выполните предыдущий шаг";
  display: block;
  font-size: .8rem;
  color: var(--ink-faint);
  margin: -0.4rem 0 1.4rem;
}
.step p { margin: 0 0 1.2rem; }

/* ---------- Управление ---------- */
.controls { display: flex; flex-wrap: wrap; gap: .8rem; align-items: center; margin: 1rem 0; }

input#msgInput {
  font-size: 1.4rem;
  letter-spacing: .35em;
  padding: .45rem .8rem;
  width: 26rem;
  max-width: 100%;
  border: 2px solid var(--ink-faint);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  outline: none;
  transition: border-color .15s;
}
input#msgInput::placeholder {
  color: var(--ink-faint);
  letter-spacing: .08em;
  font-size: 1rem;
}
input#msgInput:focus { border-color: var(--banner); }
input#msgInput.invalid { border-color: var(--err); }

.btn {
  font-family: "IBM Plex Sans", sans-serif;
  font-size: 1rem;
  font-weight: 600;
  padding: .55rem 1.3rem;
  border: 2px solid var(--banner);
  border-radius: 8px;
  background: var(--banner);
  color: #f8f8f8;
  cursor: pointer;
  transition: transform .12s, box-shadow .12s, opacity .12s;
}
.btn:hover:not(:disabled) { transform: translateY(-2px); box-shadow: 0 3px 0 rgba(32, 82, 187, .35); }
.btn:active:not(:disabled) { transform: translateY(0); box-shadow: none; }
.btn:disabled { opacity: .4; cursor: default; }

.btn-red { border-color: var(--err); background: var(--err); }
.btn-red:hover:not(:disabled) { box-shadow: 0 3px 0 rgba(255, 67, 67, .35); }

.note {
  font-size: .92rem;
  color: var(--ink-soft);
  background: #fff;
  border: 2px solid var(--line);
  border-radius: 8px;
  padding: .7rem 1rem;
  margin: 1rem 0;
  min-height: 1rem;
}
.note:empty { display: none; }

/* ---------- Таблицы и биты ---------- */
.figure {
  background: #fff;
  border: 15px solid #fff;
  box-shadow: 0 0 0 2px var(--line);
  border-radius: 4px;
  padding: .8rem;
  margin: 1.2rem 0;
  overflow-x: auto;
}

table.matrix { border-collapse: collapse; margin: 0 auto; }
table.matrix th, table.matrix td {
  border: 1px solid var(--line);
  text-align: center;
  min-width: 2.1rem;
  height: 2.1rem;
  font-size: 1.05rem;
  padding: .1rem .3rem;
}
table.matrix th { background: var(--bg); color: var(--ink-soft); font-weight: 700; }
table.matrix th.pcol { background: var(--parity-bg); color: var(--parity); }
table.matrix td.pcol { background: var(--parity-bg); }
table.matrix td.pval { background: var(--parity-bg); color: var(--parity); font-weight: 700; }
table.matrix td.sum { color: var(--ink-faint); font-size: .8rem; white-space: nowrap; }

/* строка битов */
.bitrow { display: flex; flex-wrap: wrap; gap: 4px; justify-content: center; margin: .6rem 0; }
.bit {
  width: 2.4rem;
  text-align: center;
  user-select: none;
}
.bit .pos {
  font-size: .72rem;
  color: var(--ink-faint);
  border-bottom: 1px solid var(--line);
  padding-bottom: 1px;
  margin-bottom: 3px;
}
.bit .val {
  font-size: 1.5rem;
  font-weight: 700;
  border: 2px solid var(--line);
  border-radius: 6px;
  background: var(--bg);
  padding: .1rem 0;
  transition: background .18s, border-color .18s, color .18s, transform .18s;
}
.bit.parity .pos { color: var(--parity); }
.bit.parity .val { border-color: var(--parity); color: var(--parity); background: var(--parity-bg); }
.bit.clickable { cursor: pointer; }
.bit.clickable:hover .val { transform: translateY(-2px); border-color: var(--banner); }
.bit.flipped .val { border-color: var(--err); color: var(--err); background: var(--err-bg); animation: pulse .5s; }
.bit.corrected .val { border-color: var(--ok); color: var(--ok); background: var(--ok-bg); }
@keyframes pulse { 0% { transform: scale(1); } 40% { transform: scale(1.25); } 100% { transform: scale(1); } }

.rowlabel {
  text-align: center;
  font-family: "Inconsolata", monospace;
  font-size: .85rem;
  color: var(--ink-faint);
  margin-bottom: .2rem;
}

.syndromerow .bit .val { border-color: var(--ink-soft); }

.result-line {
  font-family: "Inconsolata", monospace;
  font-size: 1.3rem;
  text-align: center;
  padding: .5rem 0;
  overflow-wrap: break-word;
  word-break: normal;
}
.result-line .ok { color: var(--ok); font-weight: 700; }
.result-line .bad { color: var(--err); font-weight: 700; }
.result-line .info-bits { background: var(--ok-bg); border-radius: 4px; padding: 0 .3rem; }

.foot {
  padding: 2.5rem 0 3rem;
  text-align: center;
  font-size: .8rem;
  color: var(--ink-faint);
}
.foot a { color: var(--banner); }

@media (max-width: 760px) {
  .wrap { padding: 0 1.2rem; }
  .banner { padding: 2.2rem 0 1.8rem; }
  .banner h1 { font-size: 1.9rem; }
}