:root {
  --paper: #fbfcff;
  --ink: #111827;
  --navy: #123e82;
  --blue: #2f7be6;
  --pale: #d6e4f8;
  --silver-a: #ffffff;
  --silver-b: #d5e0ee;
  --silver-c: #8ea6c4;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  background: #dfe6f0;
  color: var(--ink);
  font-family: "Yu Gothic", "YuGothic", "Hiragino Kaku Gothic ProN", "Meiryo", sans-serif;
}

.stage {
  padding: 32px;
}

.cover {
  position: relative;
  width: min(72vw, 760px);
  aspect-ratio: 1 / 1.4142;
  overflow: hidden;
  background:
    linear-gradient(160deg, rgba(255,255,255,.99), rgba(244,249,255,.9) 62%, rgba(255,255,255,.99)),
    var(--paper);
  box-shadow:
    0 34px 90px rgba(18, 62, 130, .26),
    0 7px 20px rgba(17, 24, 39, .12);
}

.cover::before {
  content: "";
  position: absolute;
  inset: 20px;
  border: 1px solid rgba(18, 62, 130, .22);
  pointer-events: none;
  z-index: 4;
}

.cover::after {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  right: 0;
  width: 28px;
  background:
    linear-gradient(90deg, transparent, rgba(18,62,130,.09)),
    linear-gradient(180deg, rgba(255,255,255,.74), rgba(214,228,248,.46), rgba(255,255,255,.84));
  pointer-events: none;
}

.paper-gloss {
  position: absolute;
  inset: -18%;
  background:
    linear-gradient(112deg, transparent 0 26%, rgba(255,255,255,.82) 34%, rgba(202,222,246,.22) 39%, transparent 49%),
    radial-gradient(ellipse at 82% 14%, rgba(255,255,255,.88), transparent 18%);
  mix-blend-mode: screen;
  pointer-events: none;
  z-index: 3;
}

.promise {
  position: absolute;
  top: 38px;
  left: 56px;
  right: 56px;
  width: fit-content;
  padding: 8px 12px;
  border: 1px solid rgba(18, 62, 130, .24);
  color: var(--navy);
  background: rgba(255, 255, 255, .72);
  font-size: 15px;
  font-weight: 900;
  line-height: 1;
  z-index: 5;
}

.title-block {
  position: absolute;
  top: 116px;
  left: 56px;
  right: 56px;
  z-index: 5;
}

h1 {
  margin: 0;
  color: var(--navy);
  font-family: Arial, "Yu Gothic", "YuGothic", "Hiragino Kaku Gothic ProN", "Meiryo", sans-serif;
  font-weight: 900;
  line-height: 1;
  letter-spacing: 0;
}

h1 .title-line {
  display: flex;
  align-items: baseline;
  gap: 16px;
  flex-wrap: wrap;
}

h1 em,
h1 strong {
  display: inline-block;
  font-size: clamp(68px, 9.1vw, 100px);
  line-height: .95;
  font-style: normal;
  white-space: nowrap;
}

h1 strong {
  font-weight: 900;
  padding-right: 10px;
  background:
    linear-gradient(
      100deg,
      #123e82 0%,
      #123e82 37%,
      var(--silver-a) 45%,
      var(--silver-b) 51%,
      var(--silver-c) 56%,
      #123e82 66%,
      #123e82 100%
    );
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  -webkit-text-stroke: .8px rgba(18, 62, 130, .7);
  filter:
    drop-shadow(0 2px 0 rgba(255,255,255,.95))
    drop-shadow(0 14px 18px rgba(18,62,130,.15));
}

.reading {
  margin: 12px 0 0 4px;
  color: rgba(18, 62, 130, .58);
  font-size: 18px;
  font-weight: 800;
  letter-spacing: .14em;
}

.subtitle {
  position: absolute;
  top: 316px;
  left: 56px;
  right: 56px;
  margin: 0;
  padding: 14px 18px;
  border-left: 6px solid var(--blue);
  background:
    linear-gradient(135deg, rgba(214,228,248,.82), rgba(255,255,255,.88));
  color: #111827;
  box-shadow:
    0 12px 30px rgba(18,62,130,.1),
    inset 0 1px 0 rgba(255,255,255,.88);
  font-size: 22px;
  font-weight: 900;
  line-height: 1.45;
  z-index: 5;
}

.cover-art {
  position: absolute;
  left: 50%;
  bottom: 198px;
  width: 66%;
  transform: translateX(-50%);
  opacity: .82;
  filter:
    grayscale(.06)
    saturate(.9)
    contrast(.98)
    drop-shadow(0 14px 18px rgba(18,62,130,.08));
  z-index: 2;
}

.obi {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 64px;
  padding: 20px 56px;
  background:
    linear-gradient(95deg, #0f326f, #1857b4 45%, #2f7be6 78%);
  color: white;
  box-shadow:
    0 -14px 30px rgba(18,62,130,.16),
    inset 0 1px 0 rgba(255,255,255,.28);
  z-index: 5;
}

.obi::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(112deg, transparent 0 24%, rgba(255,255,255,.3) 38%, transparent 54%);
  pointer-events: none;
}

.obi p {
  position: relative;
  margin: 0;
  font-size: 25px;
  font-weight: 900;
  line-height: 1.3;
  text-shadow: 0 1px 8px rgba(0,0,0,.15);
}

.footer {
  position: absolute;
  left: 56px;
  right: 56px;
  bottom: 28px;
  display: flex;
  justify-content: flex-start;
  gap: 18px;
  color: rgba(18,62,130,.72);
  font-family: Arial, sans-serif;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .08em;
  z-index: 5;
}

@media (max-width: 760px) {
  .stage {
    padding: 12px;
  }

  .cover {
    width: calc(100vw - 24px);
  }

  .promise,
  .title-block,
  .subtitle,
  .footer {
    left: 34px;
    right: 34px;
  }

  .promise {
    font-size: 13px;
  }

  .title-block {
    top: 92px;
  }

  h1 em,
  h1 strong {
    font-size: clamp(46px, 11.7vw, 64px);
  }

  h1 .title-line {
    gap: 9px;
  }

  .reading {
    font-size: 13px;
  }

  .subtitle {
    top: 252px;
    font-size: 16px;
  }

  .cover-art {
    bottom: 166px;
    width: 78%;
  }

  .obi {
    padding-inline: 34px;
  }

  .obi p {
    font-size: 17px;
  }

  .footer {
    font-size: 9px;
  }
}