/* ========================================================================
   chapters.css — 幕间卡 + 五幕差异化构图 + 照片电影调色 + 字幕
   每一幕有自己的构图语言,彻底告别"居中竖直堆叠"唯一模板。
   ======================================================================== */

/* ================= 幕间卡 ================= */
.act-card {
  min-height: 92svh;
  display: grid;
  place-items: center;
  position: relative;
  padding: 0 var(--pad-x);
  overflow: hidden;
}
.act-ghost {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-family: var(--font-display);
  font-size: var(--t-ghost);
  line-height: 1;
  letter-spacing: 0.04em;
  color: transparent;
  -webkit-text-stroke: 1px oklch(0.55 0.07 85 / 0.22);
  user-select: none;
  pointer-events: none;
}
.act-inner {
  position: relative;
  text-align: center;
  display: grid;
  gap: 1.1rem;
  justify-items: center;
}
.act-time {
  font-family: var(--font-display);
  font-size: var(--t-small);
  letter-spacing: 0.5em;
  text-indent: 0.5em; /* 补偿末字符 tracking */
  color: var(--gold);
}
.act-name {
  font-size: var(--t-act);
  font-weight: 400;
  letter-spacing: 0.34em;
  text-indent: 0.34em;
}
.act-intro {
  font-size: var(--t-body);
  color: var(--ivory-dim);
  letter-spacing: 0.06em;
}
.act-rule {
  width: 3.4rem;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--gold), transparent);
}

/* ================= 章节容器 ================= */
.chapter {
  position: relative;
  padding: calc(var(--gap-ch) / 2) var(--pad-x);
  display: grid;
}
.chapter + .chapter { margin-top: calc(var(--gap-ch) / 3); }

.scene-no {
  font-family: var(--font-display);
  font-size: var(--t-meta);
  letter-spacing: 0.34em;
  color: var(--ivory-faint);
}

/* ================= 照片:电影调色 ================= */
.photo-grade {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  /* 金色发丝框 + 深投影 */
  box-shadow:
    0 0 0 1px oklch(0.82 0.12 85 / 0.16),
    0 22px 60px -18px oklch(0.05 0.02 275 / 0.85),
    0 6px 18px -8px oklch(0.05 0.02 275 / 0.6);
  background: var(--night-soft);
  transform: translateZ(0);
}
.photo-grade img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: contrast(1.06) saturate(0.94) brightness(0.98);
  transition: transform 0.9s var(--e-out);
}
/* 暖金-玫瑰的柔光罩:统一 24 张照片的色温 */
.photo-grade::after {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(160deg,
      oklch(0.75 0.11 80 / calc(var(--photo-warmth) * 0.9)) 0%,
      transparent 42%,
      oklch(0.45 0.12 20 / calc(var(--photo-warmth) * 0.7)) 100%);
  mix-blend-mode: soft-light;
}
/* 照片内暗角 */
.photo-grade::before {
  content: '';
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: radial-gradient(120% 100% at 50% 42%,
    transparent 58%, oklch(0.08 0.02 275 / 0.38) 100%);
}
@media (hover: hover) {
  .photo-grade:hover img { transform: scale(1.025); }
}

/* ================= 字幕(电影字幕样式) ================= */
.sub {
  display: grid;
  gap: 0.5rem;
  justify-items: start;
}
.sub .sub-emoji {
  font-size: 1.15em;
  filter: drop-shadow(0 0 10px oklch(0.82 0.12 85 / 0.35));
}
.sub .sub-text {
  font-family: var(--font-hand);
  font-size: calc(var(--t-cap) * 1.08);
  line-height: 1.95;
  letter-spacing: 0.04em;
  color: var(--ivory);
  max-width: 21em;
}
.sub .sub-rule {
  width: 2.2rem;
  height: 1px;
  background: var(--gold-faint);
}

/* ================= 构图 treatments ================= */

/* ---- ember 余烬小像(一幕开篇:小而珍贵) ---- */
.t-ember .ch-stage {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: clamp(1.6rem, 5vw, 4rem);
  align-items: center;
  max-width: 62rem;
  margin-inline: auto;
  width: 100%;
}
.t-ember .photo-grade { max-width: 340px; width: 100%; aspect-ratio: 3 / 4; justify-self: end; }
.t-ember .frame-col { display: grid; gap: 0.9rem; justify-items: end; }

/* ---- drift 漂移(图偏一侧,字悬对侧,垂直错位) ---- */
.t-drift-l .ch-stage,
.t-drift-r .ch-stage {
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  gap: clamp(1.6rem, 5vw, 4.5rem);
  align-items: center;
  max-width: 72rem;
  margin-inline: auto;
  width: 100%;
}
.t-drift-r .ch-stage { grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); }
.t-drift-r .frame-col { order: 2; }
.t-drift-r .side-col  { order: 1; justify-items: end; text-align: right; }
.t-drift-r .side-col .sub { justify-items: end; }
.t-drift-l .photo-grade { aspect-ratio: 4 / 5; }
.t-drift-r .photo-grade { aspect-ratio: 4 / 5; }
.side-col { display: grid; gap: 1.2rem; }
/* 垂直呼吸错位:让相邻章节不在同一水平线 */
.t-drift-l .side-col { transform: translateY(clamp(1rem, 6vh, 3.4rem)); }
.t-drift-r .side-col { transform: translateY(calc(clamp(1rem, 6vh, 3.4rem) * -1)); }

/* ---- pair 双联(两图错落) ---- */
.t-pair .ch-stage {
  max-width: 74rem;
  margin-inline: auto;
  width: 100%;
  display: grid;
  gap: 1.4rem;
}
.t-pair .pair-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(1.2rem, 3.5vw, 2.6rem);
  align-items: start;
}
.t-pair .pair-grid > .frame:nth-child(2) {
  transform: translateY(clamp(1.8rem, 7vh, 4.6rem));
}
.t-pair .frame { display: grid; gap: 0.9rem; }
.t-pair .photo-grade { aspect-ratio: 4 / 5; }
.t-pair .group-sub { max-width: 30em; }

/* ---- bleed 全出血(上海章:一整屏的亲密) ---- */
.t-bleed { padding-left: 0; padding-right: 0; }
.t-bleed .ch-stage { width: 100%; }
.t-bleed .photo-grade {
  border-radius: 0;
  box-shadow: none;
  width: 100%;
  height: min(92svh, 56rem);
}
.t-bleed .photo-grade img { height: 100%; }
.t-bleed .scene-no {
  position: absolute;
  top: 1.6rem;
  left: var(--pad-x);
  z-index: 2;
}
.t-bleed .bleed-sub {
  position: absolute;
  z-index: 2;
  left: 50%;
  bottom: clamp(1.8rem, 6vh, 4rem);
  transform: translateX(-50%);
  width: min(92%, 38em);
  text-align: center;
  display: grid;
  gap: 0.5rem;
  justify-items: center;
}
.t-bleed .bleed-sub .sub-text {
  font-family: var(--font-hand);
  font-size: calc(var(--t-cap) * 1.08);
  line-height: 1.95;
  color: var(--ivory);
  text-shadow: 0 1px 18px oklch(0.05 0.02 275 / 0.9), 0 1px 4px oklch(0.05 0.02 275 / 0.8);
}
/* 底部压暗保证字幕可读 */
.t-bleed .photo-grade .bleed-shade {
  position: absolute;
  inset: auto 0 0 0;
  height: 46%;
  z-index: 1;
  pointer-events: none;
  background: linear-gradient(180deg, transparent, oklch(0.08 0.02 275 / 0.72));
}

/* ---- spotlight 聚光灯(合照/献花:被光抱住) ---- */
.t-spotlight .ch-stage {
  display: grid;
  justify-items: center;
  gap: 1.4rem;
  max-width: 46rem;
  margin-inline: auto;
  width: 100%;
  position: relative;
}
.t-spotlight .frame { display: grid; gap: 1.1rem; justify-items: center; position: relative; }
.t-spotlight .photo-grade {
  width: min(100%, 30rem);
  aspect-ratio: 4 / 5;
}
/* 聚光:照片背后的柔金光场 */
.t-spotlight .spot {
  position: absolute;
  inset: -26% -34%;
  z-index: -1;
  pointer-events: none;
  background: radial-gradient(52% 44% at 50% 44%,
    oklch(0.72 0.11 80 / 0.22) 0%,
    oklch(0.6 0.12 60 / 0.10) 45%,
    transparent 75%);
}
.t-spotlight .sub { justify-items: center; text-align: center; }
.t-spotlight .sub .sub-text { text-align: center; }

/* ---- duet 对页(嘟嘴,两图相向) ---- */
.t-duet .ch-stage {
  max-width: 66rem;
  margin-inline: auto;
  width: 100%;
  display: grid;
  gap: 2rem;
  justify-items: center;
}
.t-duet .duet-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(1rem, 4vw, 3rem);
  align-items: center;
  width: 100%;
}
.t-duet .frame { display: grid; gap: 0.9rem; }
.t-duet .frame--left  { justify-items: end; }
.t-duet .frame--right { justify-items: start; }
.t-duet .frame--left .sub { justify-items: end; }
.t-duet .photo-grade {
  aspect-ratio: 3 / 4;
  width: min(100%, 22rem);
  transition: transform 1.1s var(--e-back);
}
.t-duet .frame--left .photo-grade  { transform: rotate(-2.5deg); }
.t-duet .frame--right .photo-grade { transform: rotate(2.5deg); }
/* 靠近状态(rituals.js 切换) */
.t-duet.is-kissing .frame--left .photo-grade  { transform: rotate(-5deg) translateX(9%) scale(1.02); }
.t-duet.is-kissing .frame--right .photo-grade { transform: rotate(5deg) translateX(-9%) scale(1.02); }

/* ================= 仪式按钮(通用) ================= */
.rite-btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.6em;
  padding: 0.85em 1.7em;
  font-size: var(--t-small);
  letter-spacing: 0.22em;
  text-indent: 0.22em;
  color: var(--gold);
  border: 1px solid oklch(0.82 0.12 85 / 0.35);
  border-radius: 999px;
  background: oklch(0.26 0.045 295 / 0.4);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  transition: border-color 0.5s var(--e-out), color 0.5s var(--e-out),
              background 0.5s var(--e-out), transform 0.5s var(--e-out);
}
.rite-btn:hover {
  border-color: var(--gold);
  background: oklch(0.30 0.05 295 / 0.55);
  transform: translateY(-2px);
}
.rite-btn:active { transform: translateY(0) scale(0.98); }

/* ================= 移动端:所有构图收拢为单列,但保留性格 ================= */
@media (max-width: 720px) {
  .t-ember .ch-stage,
  .t-drift-l .ch-stage,
  .t-drift-r .ch-stage {
    grid-template-columns: 1fr;
  }
  .t-ember .photo-grade { max-width: 74%; justify-self: start; }
  .t-ember .frame-col { justify-items: start; }
  /* drift 在移动端:图仍然偏一侧(宽度 88%),保留左右呼吸 */
  .t-drift-l .frame-col { justify-self: start; width: 88%; }
  .t-drift-r .frame-col { justify-self: end; width: 88%; order: 0; }
  .t-drift-r .side-col { order: 1; justify-items: start; text-align: left; }
  .t-drift-r .side-col .sub { justify-items: start; }
  .t-drift-l .side-col, .t-drift-r .side-col { transform: none; margin-top: 1.2rem; }

  .t-pair .pair-grid { grid-template-columns: 1fr; }
  .t-pair .pair-grid > .frame:nth-child(2) {
    transform: none;
    width: 88%;
    justify-self: end;
  }
  .t-bleed .photo-grade { height: 74svh; }

  .t-duet .duet-grid { gap: 0.7rem; }
  .t-duet .photo-grade { aspect-ratio: 3 / 4.4; }

  .sub .sub-text { font-size: var(--t-body); }
}