/* 影翻棋 · 落地页 */

html {
  scroll-behavior: smooth;
}

.page {
  overflow-x: clip;
}

.rule-line {
  display: inline-block;
  flex: none;
  width: 40px;
  height: 1.5px;
  background: currentColor;
}

/* ===== 页眉 ===== */
.masthead {
  position: relative;
  z-index: 3;
  max-width: 1200px;
  margin: 0 auto;
  padding: 28px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
}

.brand__text {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.brand__name {
  font-family: var(--font-brush);
  font-size: 30px;
  line-height: 1;
}

.brand__latin {
  font-family: var(--font-latin);
  font-size: 12px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--ink-mute);
}

.nav {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 28px;
  font-size: 17px;
}

.nav__links {
  display: flex;
  flex-wrap: wrap;
  gap: 28px;
}

.nav__actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav .music-toggle {
  border-width: 1.5px;
  border-color: rgba(29, 26, 23, 0.3);
}

.nav .music-toggle .icon {
  width: 20px;
  height: 20px;
}

.nav__play {
  padding: 0 22px;
  border-radius: 4px;
  font-size: 17px;
  letter-spacing: 0.2em;
}

/* 主按钮（大） */
.btn--hero {
  gap: 12px;
  min-height: 58px;
  padding: 0 34px;
  border-radius: 4px;
  font-size: 21px;
  letter-spacing: 0.24em;
  box-shadow: 0 3px 0 var(--cinnabar-deep), 0 12px 24px rgba(126, 30, 18, 0.22);
}

.btn--hero .icon {
  width: 20px;
  height: 20px;
  stroke-width: 2;
}

.btn--hero-alt {
  min-height: 58px;
  padding: 0 30px;
  border-radius: 4px;
  font-size: 19px;
  letter-spacing: 0.18em;
}

/* ===== 首屏 ===== */
.hero {
  position: relative;
  z-index: 2;
  padding: 16px 24px 120px;
}

.hero__hills {
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 240px;
  pointer-events: none;
}

.hero__inner {
  position: relative;
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 56px;
}

.hero__copy {
  flex: 1 1 520px;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

.hero__kicker {
  margin: 0;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 16px;
  letter-spacing: 0.32em;
  color: var(--cinnabar);
}

.hero__title {
  margin: 20px 0 0;
  font-family: var(--font-brush);
  font-weight: 400;
  font-size: clamp(96px, 13vw, 188px);
  line-height: 0.95;
  letter-spacing: 0.02em;
}

.hero__latin {
  margin: 14px 0 0;
  font-family: var(--font-latin);
  font-style: italic;
  font-size: 25px;
  color: #4A433B;
}

.hero__lead {
  margin: 30px 0 0;
  max-width: 30em;
  font-size: 19px;
  line-height: 1.95;
  color: var(--ink-2);
  text-wrap: pretty;
}

.hero__actions {
  margin-top: 40px;
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.hero__facts {
  margin: 40px 0 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 14px 28px;
  font-size: 16px;
  color: var(--ink-3);
}

.hero__facts li {
  display: flex;
  align-items: center;
  gap: 10px;
}

.hero__facts li::before {
  content: '';
  width: 7px;
  height: 7px;
  background: var(--cinnabar);
  transform: rotate(45deg);
}

/* 首屏插画：按 540×620 的画稿等比缩放，--u 为画稿中的 1px */
.hero__figure {
  --u: calc(100cqw / 540);
  position: relative;
  flex: 1 1 460px;
  max-width: 540px;
  min-width: 0;
  margin: 0;
  container-type: inline-size;
}

.hero__stage {
  position: relative;
  width: 100%;
  aspect-ratio: 540 / 600;
}

.hero__stage > * {
  position: absolute;
}

.hero__glow {
  left: calc(120 * var(--u));
  top: 0;
  width: calc(380 * var(--u));
  height: calc(380 * var(--u));
  border-radius: 50%;
  background: radial-gradient(circle, #E8DBC0 0%, #ECE1CA 52%, rgba(236, 225, 202, 0) 71%);
}

.hero__peak {
  left: calc(-30 * var(--u));
  top: calc(150 * var(--u));
  width: calc(560 * var(--u));
  height: calc(220 * var(--u));
}

.hero__board {
  left: calc(30 * var(--u));
  top: calc(312 * var(--u));
  width: calc(420 * var(--u));
  height: calc(270 * var(--u));
  transform: rotate(-3deg);
  border-radius: 3px;
  background-color: #DDBD86;
  background-image:
    linear-gradient(rgba(74, 51, 32, 0.8) 1.5px, transparent 1.5px),
    linear-gradient(90deg, rgba(74, 51, 32, 0.8) 1.5px, transparent 1.5px),
    radial-gradient(ellipse at 28% 18%, rgba(255, 244, 215, 0.7), rgba(255, 244, 215, 0) 62%),
    repeating-linear-gradient(176deg, rgba(120, 72, 30, 0.07) 0 2px, rgba(120, 72, 30, 0) 2px 11px),
    linear-gradient(180deg, #E8CD9A, #D4AF74);
  background-size:
    calc(80 * var(--u)) calc(80 * var(--u)),
    calc(80 * var(--u)) calc(80 * var(--u)),
    auto,
    auto,
    auto;
  background-position:
    calc(50 * var(--u)) calc(34 * var(--u)),
    calc(50 * var(--u)) calc(34 * var(--u)),
    0 0,
    0 0,
    0 0;
  box-shadow:
    0 0 0 calc(10 * var(--u)) #7A4B23,
    0 0 0 calc(11 * var(--u)) #5C3618,
    0 30px 44px rgba(60, 35, 15, 0.28);
}

.hero__pc {
  position: absolute;
  left: calc(var(--x) * var(--u));
  top: calc(var(--y) * var(--u));
  width: calc(62 * var(--u));
  height: calc(62 * var(--u));
  font-size: calc(27 * var(--u));
}

.hero__pc--face {
  font-size: calc(33 * var(--u));
}

/* 影子里的「砲」 */
.hero__shadow {
  left: calc(118 * var(--u));
  top: calc(330 * var(--u));
  width: calc(250 * var(--u));
  height: calc(250 * var(--u));
  border-radius: 50%;
  transform: scaleY(0.4) skewX(-32deg);
  background: radial-gradient(circle, rgba(29, 26, 23, 0.5) 0%, rgba(29, 26, 23, 0.34) 42%, rgba(29, 26, 23, 0) 70%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: calc(136 * var(--u));
  color: rgba(16, 13, 10, 0.82);
  filter: blur(0.6px);
}

.hero__strokes {
  inset: 0;
  width: 100%;
  height: calc(620 * var(--u));
  overflow: visible;
  fill: none;
  stroke-linecap: round;
}

.hero__lifted {
  left: calc(98 * var(--u));
  top: calc(128 * var(--u));
  width: calc(184 * var(--u));
  height: calc(184 * var(--u));
  font-size: calc(88 * var(--u));
  transform: rotate(-14deg);
  box-shadow:
    inset 0 0 0 calc(3 * var(--u)) rgba(90, 18, 8, 0.55),
    inset 0 calc(8 * var(--u)) calc(12 * var(--u)) rgba(255, 196, 166, 0.35),
    inset 0 calc(-10 * var(--u)) calc(16 * var(--u)) rgba(60, 10, 4, 0.35),
    0 calc(6 * var(--u)) 0 #701A0D,
    0 calc(12 * var(--u)) 0 #52130A;
}

.hero__lifted::before {
  border-width: calc(3 * var(--u));
}

.hero__poem {
  right: 0;
  top: calc(24 * var(--u));
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: calc(18 * var(--u));
}

.hero__verse {
  margin: 0;
  writing-mode: vertical-rl;
  font-family: var(--font-poem);
  font-size: calc(42 * var(--u));
  line-height: 1.25;
  letter-spacing: 0.14em;
}

.hero__poem-seal {
  width: calc(32 * var(--u));
  height: calc(32 * var(--u));
  font-size: calc(22 * var(--u));
  transform: rotate(3deg);
}

.hero__caption {
  padding-left: calc(30 * var(--u));
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 15px;
  line-height: 1.6;
  color: var(--ink-3);
}

.hero__caption .rule-line {
  width: 32px;
  height: 1px;
}

/* ===== 通用区块 ===== */
.section {
  position: relative;
  z-index: 2;
  padding: 104px 24px 112px;
  border-top: 1px solid var(--line);
}

.section--tinted {
  background: rgba(214, 196, 160, 0.22);
  border-bottom: 1px solid rgba(29, 26, 23, 0.1);
}

.section__inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 56px;
}

.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
}

.section__titles {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.section__kicker {
  font-size: 15px;
  letter-spacing: 0.4em;
  color: var(--cinnabar);
}

.section__title {
  margin: 0;
  font-family: var(--font-brush);
  font-weight: 400;
  font-size: clamp(48px, 8vw, 68px);
  line-height: 1.05;
}

.section__aside {
  margin: 0;
  max-width: 24em;
  font-size: 18px;
  line-height: 1.8;
  color: var(--ink-3);
}

/* ===== 玩法三步 ===== */
.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(340px, 100%), 1fr));
  gap: 28px;
}

.step {
  padding: 32px;
  display: flex;
  flex-direction: column;
  gap: 24px;
  background: var(--paper-card);
  border: 1px solid var(--line);
}

.step__head {
  display: flex;
  align-items: baseline;
  gap: 16px;
}

.step__num {
  font-family: var(--font-brush);
  font-size: 52px;
  line-height: 1;
  color: var(--cinnabar);
}

.step__title {
  margin: 0;
  font-size: 26px;
  font-weight: 700;
}

.step__text {
  margin: 0;
  font-size: 17px;
  line-height: 1.85;
  color: var(--ink-2);
  text-wrap: pretty;
}

.step__art {
  height: 176px;
  border-radius: 2px;
  background: linear-gradient(180deg, #E6CA96, #D8B47A);
  box-shadow: inset 0 0 0 1px rgba(92, 54, 24, 0.25);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
}

.step__art--row {
  flex-direction: row;
  gap: 28px;
}

/* 壹：两排扣置的棋子 */
.mini-board {
  container-type: inline-size;
}

.mini-row {
  display: flex;
  gap: 4px;
}

.mini-row .pc {
  --s: min(29px, calc((100cqw - 56px) / 9));
  --ring: 1px;
  --d1: 1px;
  --d2: 2px;
  --d3: 4px;
  --blur: 5px;
  width: var(--s);
  height: var(--s);
  font-size: calc(var(--s) * 0.45);
}

.mini-row .pc-face {
  font-size: calc(var(--s) * 0.55);
}

.mini-board__note {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  letter-spacing: 0.12em;
  color: #5C3A1C;
}

.mini-board__note span {
  width: 34px;
  border-top: 1px dashed rgba(92, 58, 28, 0.6);
}

/* 贰：马位的八个落点 */
.knight-grid {
  position: relative;
  flex: none;
  width: 137px;
  height: 137px;
  background-image:
    linear-gradient(rgba(74, 51, 32, 0.6) 1px, transparent 1px),
    linear-gradient(90deg, rgba(74, 51, 32, 0.6) 1px, transparent 1px);
  background-size: 34px 34px;
}

.knight-dot {
  position: absolute;
  left: calc(var(--x) * 34px - 6px);
  top: calc(var(--y) * 34px - 6px);
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: rgba(29, 26, 23, 0.55);
  box-shadow: 0 0 0 3px rgba(244, 238, 225, 0.45);
}

.knight-grid__pc {
  position: absolute;
  left: 50px;
  top: 50px;
  width: 36px;
  height: 36px;
  font-size: 16px;
}

.knight-label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 14px;
  color: var(--wood-ink);
}

.knight-label__kicker {
  font-size: 13px;
  letter-spacing: 0.1em;
  opacity: 0.8;
}

.knight-label__name {
  font-family: var(--font-brush);
  font-size: 34px;
  line-height: 1;
}

/* 叁：落子 → 翻面 → 现形 */
.flip-demo {
  gap: 14px;
}

.flip-demo__stage {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  font-size: 13px;
  color: var(--wood-ink);
}

.flip-demo__pc {
  width: 54px;
  height: 54px;
  font-size: 24px;
}

.flip-demo__pc--face {
  font-size: 29px;
}

.flip-demo__edge {
  width: 54px;
  height: 54px;
  display: flex;
  justify-content: center;
}

.flip-demo__edge span {
  width: 16px;
  height: 54px;
  border-radius: 50%;
  background: linear-gradient(90deg, #841F0F 0%, #B9351F 38%, #7C5228 52%, #E9D3A3 64%, #F2DFB4 100%);
  box-shadow: 0 6px 8px rgba(40, 25, 10, 0.3);
}

.flip-demo__arrow {
  width: 22px;
  height: 22px;
  margin-bottom: 26px;
  color: #5C3A1C;
  stroke-width: 1.8;
}

/* ===== 棋子谱 ===== */
.guide {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(260px, 100%), 1fr));
  gap: 20px;
}

.guide__card {
  padding: 26px 24px;
  display: flex;
  flex-direction: column;
  gap: 18px;
  background: var(--paper-soft);
  border: 1px solid rgba(29, 26, 23, 0.1);
}

.guide__head {
  display: flex;
  align-items: center;
  gap: 16px;
}

.guide__pair {
  display: flex;
  align-items: center;
}

.guide__pair .pc {
  width: 52px;
  height: 52px;
  font-size: 28px;
}

.guide__pair .pc-lq {
  font-size: 23px;
}

.guide__pair .pc:first-child {
  z-index: 1;
}

.guide__pair .pc + .pc {
  margin-left: -12px;
}

.guide__names {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.guide__name {
  margin: 0;
  font-family: var(--font-brush);
  font-weight: 400;
  font-size: 32px;
  line-height: 1;
}

.guide__latin {
  font-family: var(--font-latin);
  font-style: italic;
  font-size: 16px;
  color: var(--ink-mute);
}

.guide__rule {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-2);
  text-wrap: pretty;
}

.tag-relaxed {
  align-self: flex-start;
  padding: 3px 9px;
  border: 1px solid rgba(179, 48, 30, 0.55);
  border-radius: 2px;
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--cinnabar-text);
}

/* ===== 对局规矩 ===== */
.rules {
  flex-direction: row;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: 64px;
}

.rules__aside {
  flex: 0 1 260px;
  display: flex;
  justify-content: center;
  gap: 18px;
}

.rules__motto {
  margin: 0;
  writing-mode: vertical-rl;
  font-family: var(--font-brush);
  font-size: 104px;
  line-height: 1;
  letter-spacing: 0.06em;
}

.rules__sub {
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  gap: 10px;
  padding-bottom: 6px;
}

.rules__sub-text {
  writing-mode: vertical-rl;
  font-size: 15px;
  letter-spacing: 0.3em;
  color: var(--ink-mute);
}

.rules__seal {
  width: 30px;
  height: 30px;
  font-size: 20px;
}

.rules__main {
  flex: 1 1 560px;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 40px;
}

.rules__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
}

.rules__item {
  display: flex;
  gap: 24px;
  padding: 26px 0;
  border-top: 1px dashed rgba(29, 26, 23, 0.28);
}

.rules__num {
  flex: none;
  width: 44px;
  height: 44px;
  border: 1.5px solid var(--cinnabar);
  border-radius: 3px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-brush);
  font-size: 26px;
  color: var(--cinnabar);
}

.rules__body {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.rules__title {
  margin: 0;
  font-size: 23px;
  font-weight: 700;
}

.rules__text {
  margin: 0;
  font-size: 17px;
  line-height: 1.85;
  color: var(--ink-2);
  text-wrap: pretty;
}

.rules__more {
  margin: 0;
  font-size: 15px;
  color: var(--ink-mute);
}

/* ===== 入局 ===== */
.cta {
  position: relative;
  z-index: 2;
  overflow: hidden;
  padding: 128px 24px 150px;
  background: var(--ink);
  color: var(--paper);
  text-align: center;
}

.cta__sun {
  position: absolute;
  right: 10%;
  top: 56px;
  width: 220px;
  height: 220px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(179, 48, 30, 0.9) 0%, rgba(179, 48, 30, 0.75) 58%, rgba(179, 48, 30, 0) 72%);
}

.cta__hills {
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 260px;
  pointer-events: none;
}

.cta__inner {
  position: relative;
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 22px;
}

.cta__title {
  margin: 0;
  font-family: var(--font-brush);
  font-weight: 400;
  font-size: clamp(44px, 6vw, 80px);
  line-height: 1.15;
  text-wrap: balance;
}

.cta__text {
  margin: 0;
  font-size: 19px;
  color: #CFC4B1;
}

.cta__btn {
  margin-top: 18px;
  padding: 0 36px;
  box-shadow: 0 3px 0 #6E1A0D;
}

/* ===== 页脚 ===== */
.footer {
  position: relative;
  z-index: 2;
  padding: 30px 24px;
}

.footer__inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  font-size: 15px;
  color: var(--ink-3);
}

.footer__brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.footer__seal {
  width: 26px;
  height: 26px;
  font-size: 17px;
}

.footer__links {
  display: flex;
  gap: 24px;
}

.footer__links a {
  color: var(--ink-3);
}

.footer__links a:hover {
  color: var(--cinnabar);
}

/* ===== 窄屏 ===== */
@media (max-width: 720px) {
  .masthead {
    padding: 20px 20px;
  }

  .nav__links {
    display: none;
  }

  .hero {
    padding: 8px 20px 96px;
  }

  .hero__inner {
    gap: 40px;
  }

  .hero__lead {
    font-size: 17px;
    line-height: 1.9;
  }

  .hero__latin {
    font-size: 21px;
  }

  .btn--hero,
  .btn--hero-alt {
    padding: 0 26px;
  }

  .section {
    padding: 72px 20px 80px;
  }

  .section__inner {
    gap: 40px;
  }

  .step {
    padding: 24px;
  }

  .rules {
    gap: 40px;
  }

  .rules__aside {
    flex-basis: 100%;
  }

  .rules__motto {
    font-size: 72px;
  }

  .rules__item {
    gap: 18px;
  }

  .cta {
    padding: 96px 20px 120px;
  }

  .cta__sun {
    right: -40px;
    top: 24px;
    width: 160px;
    height: 160px;
  }
}