:root {
  --bg: #f6f4ee;
  --ink: #111;
  --ink-soft: #555;
  --accent: #1f4dff;
  --line: #e3dfd4;
  --radius: 14px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Helvetica, Arial, sans-serif;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 28px;
  border-bottom: 1px solid var(--line);
}
.nav__brand {
  font-weight: 800;
  letter-spacing: 0.08em;
  font-size: 18px;
}
.nav__brand span {
  color: var(--accent);
  margin-left: 4px;
}
.nav__link {
  text-decoration: none;
  font-weight: 600;
  font-size: 14px;
}

.hero {
  max-width: 1100px;
  margin: 0 auto;
  padding: 48px 28px 80px;
}

.product {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
}

@media (min-width: 860px) {
  .product { grid-template-columns: 1.1fr 1fr; gap: 64px; }
}

.product__media {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  aspect-ratio: 1 / 1;
}

.product__image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.product__info { display: flex; flex-direction: column; }

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 12px;
  color: var(--ink-soft);
  margin: 0 0 12px;
}

.product__title {
  font-size: 40px;
  line-height: 1.1;
  margin: 0 0 12px;
  font-weight: 800;
}

.product__price {
  font-size: 22px;
  font-weight: 700;
  margin: 0 0 20px;
}

.product__desc {
  color: var(--ink-soft);
  margin: 0 0 28px;
}

.size__label {
  font-weight: 700;
  margin: 0 0 10px;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.size__options {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 8px;
}
.size__btn {
  min-width: 56px;
  padding: 12px 14px;
  background: #fff;
  border: 1.5px solid var(--line);
  border-radius: 10px;
  font-weight: 600;
  cursor: pointer;
  transition: border-color .15s, background .15s, color .15s;
}
.size__btn:hover { border-color: var(--ink); }
.size__btn[aria-checked="true"] {
  background: var(--ink);
  color: #fff;
  border-color: var(--ink);
}
.size__btn[disabled] {
  opacity: 0.4;
  cursor: not-allowed;
}
.size__hint {
  font-size: 13px;
  color: var(--ink-soft);
  margin: 6px 0 24px;
}

.buy {
  display: block;
  width: 100%;
  padding: 18px 22px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: transform .05s, opacity .15s;
}
.buy:hover:not(:disabled) { opacity: 0.92; }
.buy:active:not(:disabled) { transform: translateY(1px); }
.buy:disabled {
  background: #c9c4b6;
  cursor: not-allowed;
}

.trust {
  list-style: none;
  padding: 0;
  margin: 24px 0 0;
  font-size: 13px;
  color: var(--ink-soft);
  display: grid;
  gap: 6px;
}
.trust li::before {
  content: "✓ ";
  color: var(--accent);
  font-weight: 700;
}

.footer {
  border-top: 1px solid var(--line);
  padding: 24px 28px;
  text-align: center;
  font-size: 13px;
  color: var(--ink-soft);
}
.footer p { margin: 0; }

.social {
  display: flex;
  justify-content: center;
  gap: 14px;
  margin-bottom: 12px;
}
.social__link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid var(--line);
  color: var(--ink);
  text-decoration: none;
  transition: background .15s, color .15s, border-color .15s;
}
.social__link:hover {
  background: var(--ink);
  color: #fff;
  border-color: var(--ink);
}