.bk { padding-block-end: 30px; }
.bk-cover { background: var(--coral); color: #fff; position: relative; overflow: hidden; }
.bk-cover::after { content: ""; position: absolute; inset: auto -10% -60px; block-size: 120px; background: #fff; border-radius: 50% 50% 0 0; }
.bk-cover__in { display: grid; grid-template-columns: 1.2fr .8fr; gap: 40px; align-items: center; padding-block: 40px 90px; }
.bk-cover .hand { font-size: 34px; color: var(--sun); }
.bk-cover h1 { font-size: clamp(34px, 4.6vw, 58px); margin-block: 6px 14px; }
.bk-cover p { font-size: 19px; max-inline-size: 560px; }
.bk-cover figure { justify-self: center; background: #fff; border-radius: 50%; padding: 18px; box-shadow: 0 18px 40px rgb(0 0 0 / .18); transform: rotate(-6deg); }
.bk-cover figure img { inline-size: min(300px, 60vw); }
.bk-line { position: relative; display: grid; gap: 56px; margin-block: 30px 60px; }
.bk-line::before { content: ""; position: absolute; inset-block: 0; inset-inline-start: 50%; border-inline-start: 4px dotted var(--coral); }
.bk-ch { display: grid; grid-template-columns: 1fr 1fr; gap: 70px; align-items: center; position: relative; }
.bk-ch::after { content: attr(data-n); position: absolute; inset-inline-start: 50%; inset-block-start: 50%; translate: -50% -50%; inline-size: 54px; block-size: 54px; border-radius: 50%; background: var(--sun); color: var(--ink); font-family: var(--f-head); font-weight: 700; font-size: 24px; display: grid; place-items: center; box-shadow: 0 0 0 6px #fff; }
.bk-ch:nth-child(even) .bk-ch__pic { order: 2; }
.bk-ch__pic img { border-radius: 30px 30px 30px 4px; aspect-ratio: 4 / 3; object-fit: cover; inline-size: 100%; box-shadow: var(--shadow); }
.bk-ch small { font-family: var(--f-hand); font-size: 28px; color: var(--coral); }
.bk-ch h2 { font-size: 28px; margin-block: 0 10px; }
.bk-ch p { font-size: 16.5px; }
.bk-rules { background: var(--ink); color: #fff; border-radius: 26px; padding: 34px; }
.bk-rules h2 { font-size: 28px; text-align: center; margin-block-end: 22px; }
.bk-rules ol { list-style: none; padding: 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; counter-reset: r; }
.bk-rules li { counter-increment: r; background: rgb(255 255 255 / .06); border-radius: 18px; padding: 20px; }
.bk-rules li::before { content: "0" counter(r); font-family: var(--f-head); font-size: 34px; color: var(--coral); display: block; line-height: 1; margin-block-end: 8px; }
.bk-rules b { display: block; font-family: var(--f-head); font-size: 18px; margin-block-end: 4px; }
.bk-rules span { font-size: 14.5px; opacity: .85; }
.bk-shelf { margin-block-start: 50px; text-align: center; }
.bk-shelf h2 { font-size: 28px; margin-block-end: 18px; }
.bk-shelf ul { list-style: none; padding: 0; display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; }
.bk-shelf a { display: inline-flex; align-items: center; gap: 10px; padding: 8px 18px 8px 8px; border-radius: 99px; border: 2px solid var(--c); text-decoration: none; color: var(--ink); font-family: var(--f-head); font-weight: 500; }
.bk-shelf img { inline-size: 40px; block-size: 40px; border-radius: 50%; object-fit: cover; }
.bk-shelf a:hover { background: var(--c); color: #fff; }
@media (max-width: 860px) {
  .bk-cover__in { grid-template-columns: 1fr; padding-block-end: 80px; }
  .bk-cover figure { display: none; }
  .bk-line::before { inset-inline-start: 22px; }
  .bk-ch { grid-template-columns: 1fr; gap: 16px; padding-inline-start: 56px; }
  .bk-ch::after { inset-inline-start: 22px; inset-block-start: 0; translate: -50% 0; }
  .bk-ch:nth-child(even) .bk-ch__pic { order: 0; }
  .bk-rules ol { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 520px) { .bk-rules ol { grid-template-columns: 1fr; } .bk-rules { padding: 24px 18px; } }