.brief-page .header--solid {
  position: sticky;
  top: 0;
  color: var(--ink);
  background: color-mix(in srgb, var(--plaster) 94%, transparent);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(10px);
  height: var(--header);
  z-index: 20;
}

.brief-page .header--solid .nav {
  color: var(--ink);
}

.brief-page .brand__mark--dark {
  display: block;
  opacity: 1;
}

.brief {
  padding: calc(var(--header) + 40px) 0 80px;
  background:
    radial-gradient(ellipse 55% 40% at 0% 0%, color-mix(in srgb, var(--fir) 8%, transparent), transparent 70%),
    var(--plaster);
}

.brief__intro h1 {
  max-width: none;
  font-size: clamp(2.2rem, 5vw, 3.4rem);
}

.brief__intro .lede {
  margin-top: 12px;
  max-width: 42ch;
  color: var(--muted);
}

.brief__progress {
  display: flex;
  flex-wrap: nowrap;
  align-items: center;
  gap: 0;
  margin: 32px 0 0;
  padding: 0;
  list-style: none;
  max-width: 100%;
  overflow-x: auto;
  white-space: nowrap;
  scrollbar-width: thin;
}

.brief__progress li {
  display: inline-flex;
  flex-shrink: 0;
  align-items: center;
  gap: 6px;
  color: var(--muted);
  font-size: 0.85rem;
}

.brief__progress li:not(:last-child)::after {
  content: "";
  display: inline-block;
  width: 16px;
  height: 1px;
  margin: 0 6px 0 2px;
  background: var(--line);
  flex-shrink: 0;
}

.brief__progress .dot {
  display: inline-grid;
  place-items: center;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: #fff;
  font-size: 0.75rem;
  font-weight: 600;
}

.brief__progress li.is-on {
  color: var(--fir);
  font-weight: 600;
}

.brief__progress li.is-on .dot {
  border-color: var(--fir);
  background: var(--fir);
  color: var(--on-fir);
}

.brief__progress li.is-done .dot {
  border-color: var(--fir);
  color: var(--fir);
}

.brief__form {
  margin-top: 36px;
  max-width: 720px;
  padding: 28px 28px 32px;
  background: #fff;
  border: 1px solid var(--line);
  border-left: 4px solid var(--fir);
}

.brief__step h2 {
  margin: 0 0 8px;
  font-size: clamp(1.35rem, 2.5vw, 1.75rem);
}

.brief__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px 18px;
  margin-top: 0;
}

.brief__grid .field--full {
  grid-column: 1 / -1;
}

.brief__step > .field {
  margin-top: 16px;
}

.brief__hint {
  margin: 0 0 20px;
  color: var(--muted);
  font-size: 0.98rem;
}

.brief__block {
  margin-top: 22px;
  padding: 18px 18px 16px;
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--plaster) 70%, #fff);
}

.brief__block-title {
  margin: 0 0 14px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--fir);
}

.brief__block .field label {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 6px;
  font-size: 0.92rem;
  font-weight: 500;
}

.field__opt {
  font-size: 0.78rem;
  font-weight: 400;
  color: var(--muted);
  letter-spacing: 0;
  text-transform: none;
}

.brief__block input,
.brief__block textarea,
.brief__block select {
  width: 100%;
  min-height: 48px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--ink);
  font: inherit;
  border-radius: 0;
  transition: border-color 0.15s ease;
}

.brief__block input:focus,
.brief__block textarea:focus,
.brief__block select:focus {
  outline: none;
  border-color: var(--fir);
}

.brief__block .field.is-invalid input,
.brief__block .field.is-invalid textarea {
  border-color: var(--danger, #8f2d2d);
}

.brief__detect {
  margin: 8px 0 0;
  font-size: 0.85rem;
  color: var(--fir);
  font-weight: 500;
}

.brief__paths {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin: 0;
  padding: 0;
  border: 0;
}

.path {
  display: block;
  cursor: pointer;
}

.path input {
  position: absolute;
  opacity: 0;
  width: 1px;
  height: 1px;
  margin: 0;
  pointer-events: none;
}

.path input[type="checkbox"]:checked + .path__body::after {
  content: "✓";
  position: absolute;
  top: 12px;
  right: 14px;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--fir, #12352c);
}

.path__body {
  position: relative;
  display: grid;
  gap: 6px;
  height: 100%;
  padding: 16px 18px;
  padding-right: 36px;
  border: 1px solid var(--line);
  background: var(--plaster);
  transition: border-color 0.2s ease, background 0.2s ease;
}

.path:hover .path__body {
  border-color: color-mix(in srgb, var(--fir) 35%, var(--line));
}

.path input:checked + .path__body,
.path input:focus-visible + .path__body {
  border-color: var(--fir);
  background: color-mix(in srgb, var(--fir) 6%, #fff);
}

.path__title {
  font-family: var(--font-display);
  font-size: 1.05rem;
  letter-spacing: -0.02em;
  color: var(--fir);
}

.path__text {
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.35;
}

.brief__paths.is-invalid .path__body {
  border-color: #b42318;
}

.brief__radios,
.brief__checks {
  display: grid;
  gap: 8px;
  margin: 18px 0 8px;
  padding: 0;
  border: 0;
}

.brief__checks {
  grid-template-columns: 1fr 1fr;
}

.field-legend {
  grid-column: 1 / -1;
  margin: 8px 0 4px;
  font-weight: 600;
  color: var(--fir);
  font-size: 0.95rem;
}

.check {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  background: var(--plaster);
  cursor: pointer;
}

.check:has(input:checked) {
  border-color: var(--fir);
  background: color-mix(in srgb, var(--fir) 6%, #fff);
}

.check input {
  margin-top: 3px;
  accent-color: var(--fir);
}

.brief__nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.brief-page .btn {
  margin-top: 0;
}

.btn--ghost {
  background: transparent;
  color: var(--fir);
  border: 1px solid var(--line);
}

.btn--ghost:hover {
  background: var(--plaster);
}

.field.is-invalid input,
.field.is-invalid textarea,
.field.is-invalid select {
  border-color: #b42318;
  outline-color: #b42318;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

@media (max-width: 720px) {
  .brief {
    padding: calc(var(--header) + 20px) 0 56px;
  }

  .brief__intro h1 {
    font-size: clamp(1.85rem, 9vw, 2.4rem);
  }

  .brief__intro .lede {
    font-size: 0.98rem;
    max-width: none;
  }

  .brief__progress {
    margin-top: 20px;
    padding-bottom: 4px;
    -webkit-overflow-scrolling: touch;
  }

  .brief__progress .label {
    display: none;
  }

  .brief__progress .dot {
    width: 30px;
    height: 30px;
    font-size: 0.8rem;
  }

  .brief__progress li:not(:last-child)::after {
    width: 12px;
    margin: 0 5px;
  }

  .brief__form {
    margin-top: 22px;
    padding: 18px 14px 22px;
    border-left-width: 3px;
  }

  .brief__step h2 {
    font-size: 1.35rem;
  }

  .brief__grid,
  .brief__paths,
  .brief__checks {
    grid-template-columns: 1fr;
  }

  .brief__grid {
    gap: 14px;
    margin-top: 14px;
  }

  .path__body {
    padding: 14px 14px;
  }

  .path__title {
    font-size: 1rem;
  }

  .path__text {
    font-size: 0.88rem;
  }

  .check {
    padding: 14px 12px;
    min-height: 48px;
    align-items: center;
  }

  .check input {
    margin-top: 0;
    width: 18px;
    height: 18px;
  }

  .brief__nav {
    flex-direction: column-reverse;
    gap: 10px;
    margin-top: 22px;
  }

  .brief__nav .btn {
    width: 100%;
    min-height: 48px;
    padding: 14px 18px;
  }

  .brief-page .field input,
  .brief-page .field textarea,
  .brief-page .field select {
    font-size: 16px; /* без зума iOS */
  }

  .brief-page .footer__bar {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
    height: auto;
    padding: 20px 0;
  }
}

@media (max-width: 420px) {
  .brief__form {
    padding: 16px 12px 20px;
  }
}