:root {
  --ink: #17201c;
  --muted: #4e5b54;
  --paper: #f8f6ef;
  --paper-deep: #ece7dc;
  --card: rgba(255, 254, 250, 0.96);
  --vermilion: #933826;
  --vermilion-dark: #74291d;
  --line: rgba(23, 32, 28, 0.24);
  --serif: "Yu Mincho", "Hiragino Mincho ProN", "Noto Serif JP", serif;
  --sans: "Yu Gothic", "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 15% 10%, rgba(255,255,255,.55), transparent 27rem),
    repeating-linear-gradient(90deg, rgba(59,53,38,.008) 0, rgba(59,53,38,.008) 1px, transparent 1px, transparent 5px),
    var(--paper);
  font-family: var(--sans);
  line-height: 1.8;
}

button, textarea, input { font: inherit; }
button { cursor: pointer; }

.page-shell {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
}

.site-header {
  min-height: 104px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
}

.site-header p, footer { color: var(--muted); font-size: .8rem; letter-spacing: .12em; }

.header-meta { display: flex; align-items: center; gap: 28px; }
.header-meta p { margin: 0; }
.history-button {
  padding: 9px 14px;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 2px;
}
.history-button:hover { color: var(--vermilion); border-color: var(--vermilion); }
.history-button:disabled { cursor: wait; opacity: .45; }

.brand {
  display: inline-flex;
  gap: 12px;
  align-items: center;
  color: var(--ink);
  text-decoration: none;
  font-family: var(--serif);
  font-weight: 700;
  letter-spacing: .16em;
}

.brand-mark {
  color: var(--vermilion);
  font-size: 1.9rem;
  line-height: 1;
}

main { min-height: calc(100vh - 190px); }

.install-guide {
  position: fixed;
  z-index: 10;
  right: max(18px, env(safe-area-inset-right));
  bottom: max(18px, env(safe-area-inset-bottom));
  left: max(18px, env(safe-area-inset-left));
  max-width: 560px;
  margin-left: auto;
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 14px;
  align-items: center;
  padding: 17px 18px;
  color: var(--ink);
  background: #fffefa;
  border: 1px solid var(--line);
  box-shadow: 0 16px 48px rgba(23, 32, 28, .18);
}

.install-guide-mark {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  color: #fff;
  background: var(--vermilion);
  border-radius: 9px;
  font-family: var(--serif);
  font-size: 1.25rem;
}

.install-guide p { margin: 0; font-size: .76rem; line-height: 1.55; }
.install-guide button { align-self: start; padding: 0 3px; color: var(--muted); background: none; border: 0; font-size: 1.35rem; line-height: 1; }

.intro {
  position: relative;
  padding: clamp(70px, 11vw, 140px) 0 100px;
  max-width: 900px;
  margin: auto;
}

.intro::after {
  content: "易";
  position: absolute;
  z-index: -1;
  top: 30px;
  right: 0;
  color: rgba(168, 69, 50, .055);
  font: 360px/.9 var(--serif);
}

.eyebrow, .card-label {
  margin: 0 0 12px;
  color: var(--vermilion);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .2em;
  text-transform: uppercase;
}

h1, h2, h3 { font-family: var(--serif); font-weight: 500; }

h1 {
  margin: 0;
  font-size: clamp(2.9rem, 7vw, 5.7rem);
  line-height: 1.3;
  letter-spacing: .08em;
}

.lead {
  max-width: 630px;
  margin: 30px 0 50px;
  color: var(--muted);
}

.question-card {
  padding: clamp(24px, 4vw, 42px);
  background: var(--card);
  border: 1px solid rgba(255,255,255,.75);
  border-radius: 4px;
  box-shadow: 0 24px 70px rgba(49, 43, 31, .09);
}

.question-card label { display: block; margin-bottom: 12px; font-family: var(--serif); font-size: 1.15rem; }

textarea {
  width: 100%;
  resize: vertical;
  padding: 16px 0;
  color: var(--ink);
  background: transparent;
  border: 0;
  border-bottom: 1px solid var(--line);
  outline: none;
}

textarea:focus { border-color: var(--vermilion); }
textarea::placeholder { color: #707a74; }

.form-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  margin-top: 24px;
}

#counter { color: var(--muted); font-size: .75rem; }

.primary-button {
  min-width: 180px;
  display: flex;
  justify-content: space-between;
  padding: 15px 22px;
  color: white;
  background: var(--vermilion);
  border: 0;
  border-radius: 10px;
  transition: background .2s, transform .2s;
}

.primary-button:hover { background: var(--vermilion-dark); transform: translateY(-2px); }
.primary-button:focus-visible, .text-button:focus-visible, .history-button:focus-visible, .back-button:focus-visible, .delete-button:focus-visible { outline: 3px solid rgba(168,69,50,.3); outline-offset: 3px; }

.prompt-copy-actions {
  display: flex;
  min-height: 48px;
  margin: 32px 0 48px;
  align-items: center;
  justify-content: flex-end;
  gap: 20px;
}
.prompt-copy-status { margin: 0; color: var(--muted); font-size: .9rem; }
.prompt-copy-status.is-error { color: var(--vermilion-dark); }
.secondary-button {
  min-height: 44px;
  padding: 10px 18px;
  color: var(--vermilion);
  background: transparent;
  border: 1px solid currentColor;
  border-radius: 4px;
}
.secondary-button:hover { color: var(--vermilion-dark); }
.secondary-button:disabled { cursor: wait; opacity: .55; }
.secondary-button:focus-visible { outline: 3px solid rgba(168,69,50,.3); outline-offset: 3px; }

.method-note {
  display: flex;
  gap: 18px;
  align-items: center;
  max-width: 430px;
  margin: 34px 0 0 auto;
  color: var(--muted);
  font-size: .78rem;
}

.method-note > span {
  flex: 0 0 45px;
  height: 45px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 50%;
  font-family: var(--serif);
}

.method-note p { margin: 0; }

.casting {
  min-height: 620px;
  padding-top: 130px;
  text-align: center;
}

.casting h2 { margin: 0 0 52px; font-size: clamp(2rem, 5vw, 3.4rem); letter-spacing: .08em; }
.casting > p:last-child { color: var(--muted); font-size: .85rem; }

.coins { height: 92px; display: flex; justify-content: center; gap: 24px; perspective: 600px; }
.coin {
  width: 68px; height: 68px; display: grid; place-items: center;
  color: var(--vermilion); border: 2px solid var(--vermilion); border-radius: 50%;
  font-family: var(--serif); font-size: 1.3rem;
  animation: toss .7s ease-in-out infinite alternate;
}
.coin:nth-child(2) { animation-delay: .13s; }
.coin:nth-child(3) { animation-delay: .26s; }
@keyframes toss { to { transform: translateY(-24px) rotateY(540deg); } }

.result { padding: 80px 0 100px; }
.result-heading { display: flex; align-items: end; justify-content: space-between; gap: 24px; }
.result-heading h2 { margin: 0; font-size: clamp(2.4rem, 5vw, 4.2rem); }
.text-button { padding: 8px 0; color: var(--vermilion); background: none; border: 0; border-bottom: 1px solid currentColor; }

blockquote {
  margin: 46px 0 54px;
  padding: 20px 28px;
  color: var(--muted);
  background: rgba(255,255,255,.72);
  border-left: 3px solid var(--vermilion);
  font-family: var(--serif);
}

.hexagram-grid { display: grid; grid-template-columns: 1fr 70px 1fr; align-items: stretch; }
.hexagram-card {
  padding: clamp(28px, 5vw, 52px);
  background: var(--card);
  border: 1px solid rgba(255,255,255,.75);
  box-shadow: 0 22px 60px rgba(49,43,31,.07);
}
.hexagram-card.primary { border-top: 3px solid var(--vermilion); }
.hexagram-card.relating { border-top: 3px solid var(--ink); }
.hexagram-card h3 { margin: 2px 0 0; font-size: clamp(2.2rem, 5vw, 3.5rem); letter-spacing: .12em; }
.hexagram-number { margin: 28px 0 0; color: var(--muted); font-size: .72rem; letter-spacing: .12em; }
.pronunciation { margin: 0 0 26px; color: var(--vermilion); font-size: .82rem; }
.judgement { margin: 0; color: var(--muted); }
.personal-message { margin-top: 28px; padding: 22px 0 0; border-top: 1px solid var(--line); }
.personal-message-label { margin: 0 0 8px; color: var(--vermilion); font-family: var(--serif); font-size: .88rem; font-weight: 700; letter-spacing: .08em; }
.personal-message p:last-child { margin: 0; color: var(--ink); line-height: 1.95; }
.relating-message { border-top-color: rgba(23, 32, 28, .32); }
.relating-message .personal-message-label { color: var(--ink); }
.change-arrow { display: grid; place-items: center; color: var(--vermilion); font: .75rem/1.8 var(--serif); letter-spacing: .2em; }

.hexagram-figure { width: 132px; display: flex; flex-direction: column-reverse; gap: 9px; }
.yao { position: relative; height: 11px; }
.yao::before, .yao::after { content: ""; position: absolute; top: 0; height: 100%; background: var(--ink); border-radius: 1px; }
.yao.yang::before { left: 0; width: 100%; }
.yao.yang::after { display: none; }
.yao.yin::before { left: 0; width: 43%; }
.yao.yin::after { right: 0; width: 43%; }
.yao.changing::before, .yao.changing::after { background: var(--vermilion); }

.interpretation, .changing-lines {
  margin-top: 34px;
  padding: clamp(28px, 5vw, 48px);
  border: 1px solid var(--line);
}
.interpretation h3 { margin: 0 0 18px; font-size: 1.6rem; }
.interpretation p:last-child { margin-bottom: 0; }
.line-reading + .line-reading { margin-top: 24px; padding-top: 24px; border-top: 1px solid var(--line); }
.line-reading h4 { margin: 3px 0 9px; font-family: var(--serif); font-size: 1.22rem; }
.line-reading p { margin: 0; color: var(--muted); }
.line-reading .yao-position { color: var(--vermilion); font-size: .76rem; letter-spacing: .06em; }
.no-change { color: var(--muted); }
.disclaimer { max-width: 740px; margin: 38px auto 0; color: var(--muted); font-size: .75rem; text-align: center; }

.record-editor {
  margin-top: 34px;
  padding: clamp(28px, 5vw, 48px);
  color: var(--ink);
  background: var(--card);
  border-top: 3px solid var(--vermilion);
  box-shadow: 0 22px 60px rgba(49,43,31,.07);
}

.record-editor-heading { display: flex; justify-content: space-between; gap: 36px; align-items: end; margin-bottom: 30px; }
.record-editor-heading h3 { margin: 0; font-size: 1.65rem; }
.record-editor-heading > p { max-width: 360px; margin: 0; color: var(--muted); font-size: .78rem; }
.record-fields { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px; align-items: start; }
.record-fields label, .history-detail label { min-width: 0; display: grid; gap: 9px; color: var(--ink); font-family: var(--serif); font-size: .92rem; }
.record-fields textarea, .history-detail textarea, .record-fields input, .history-detail input {
  min-width: 0;
  max-width: 100%;
  width: 100%;
  padding: 13px 14px;
  color: var(--ink);
  background: #fffefa;
  border: 1px solid var(--line);
  border-radius: 10px;
  outline: none;
  font-family: var(--sans);
}
.record-fields input[type="date"], .history-detail input[type="date"] {
  display: block;
  -webkit-appearance: none;
  appearance: none;
  box-sizing: border-box;
  width: -webkit-fill-available;
  inline-size: -webkit-fill-available;
  min-inline-size: 0;
  max-inline-size: 100%;
}
.record-fields textarea:focus, .history-detail textarea:focus, .record-fields input:focus, .history-detail input:focus { border-color: var(--vermilion); box-shadow: 0 0 0 3px rgba(147,56,38,.1); }
.record-fields textarea, .history-detail textarea { resize: vertical; }
.record-actions { display: flex; align-items: center; justify-content: space-between; gap: 24px; margin-top: 28px; }
.record-status { margin: 0; color: var(--muted); font-size: .78rem; }
.record-status.is-error { color: var(--vermilion-dark); font-weight: 700; }

.history { padding: 80px 0 100px; }
.history-note { max-width: 760px; margin: 34px 0 48px; padding: 16px 20px; color: var(--muted); background: rgba(255,255,255,.65); border-left: 3px solid var(--vermilion); font-size: .78rem; }
.history-summary { min-height: 36px; }
.history-summary p { color: var(--muted); font-size: .8rem; }
.history-list { display: grid; gap: 18px; }
.history-card {
  display: grid;
  grid-template-columns: minmax(140px, .65fr) minmax(240px, 1.35fr) auto;
  gap: 28px;
  align-items: center;
  padding: 24px 28px;
  background: var(--card);
  border: 1px solid rgba(255,255,255,.8);
  border-left: 3px solid var(--vermilion);
  box-shadow: 0 12px 35px rgba(49,43,31,.055);
}
.history-card-date { margin: 0 0 4px; color: var(--muted); font-size: .74rem; }
.history-card h3 { margin: 0; font-size: 1.25rem; }
.history-card-question { margin: 0; color: var(--muted); font-family: var(--serif); }
.history-card button { white-space: nowrap; }
.history-empty { padding: 80px 20px; text-align: center; border: 1px solid var(--line); }
.history-empty > span { width: 64px; height: 64px; display: grid; place-items: center; margin: 0 auto 18px; color: var(--vermilion); border: 1px solid var(--vermilion); border-radius: 50%; font-family: var(--serif); font-size: 1.35rem; }
.history-empty h3 { margin: 0; font-size: 1.4rem; }
.history-empty p { margin: 8px 0 0; color: var(--muted); }

.history-detail { max-width: 820px; margin: 0 auto; padding: clamp(28px, 5vw, 50px); background: var(--card); border-top: 3px solid var(--vermilion); box-shadow: 0 22px 60px rgba(49,43,31,.07); }
.back-button { padding: 6px 0; color: var(--vermilion); background: none; border: 0; }
.history-detail-date { margin: 38px 0 0; color: var(--muted); font-size: .78rem; }
.history-detail > h3 { margin: 4px 0 0; font-size: clamp(1.9rem, 4vw, 2.8rem); }
.history-detail blockquote { margin: 28px 0; }
.history-detail-message { margin: 0 0 24px; padding: 24px; background: var(--paper); border-left: 3px solid var(--vermilion); }
.history-detail-message p:last-child { margin: 0; line-height: 1.95; }
#history-detail-relating-message-box { border-left-color: var(--ink); }
#history-detail-relating-message-box .card-label { color: var(--ink); }
.history-detail-guidance { margin-bottom: 34px; color: var(--muted); }
.history-detail .history-changing-lines { margin: 0 0 34px; padding: 24px; }
.history-detail form { display: grid; gap: 22px; }
.detail-buttons { display: flex; gap: 20px; align-items: center; }
.delete-button { padding: 10px 0; color: var(--vermilion-dark); background: none; border: 0; border-bottom: 1px solid currentColor; }

footer { min-height: 86px; display: flex; justify-content: space-between; align-items: center; border-top: 1px solid var(--line); }
.footer-meta { display: flex; align-items: center; gap: 18px; }
#app-version { padding-left: 18px; border-left: 1px solid var(--line); letter-spacing: .06em; }
[hidden] { display: none !important; }

@media (max-width: 720px) {
  .page-shell { width: min(100% - 28px, 1120px); }
  .site-header { min-height: 82px; }
  .site-header p { display: none; }
  .header-meta { gap: 0; }
  .intro { padding-top: 70px; }
  .intro::after { top: 60px; font-size: 210px; }
  .lead { margin-bottom: 36px; }
  .form-footer { align-items: flex-end; }
  .primary-button { min-width: 160px; }
  .method-note { margin-left: 0; }
  .result-heading { align-items: flex-start; flex-direction: column; }
  blockquote { margin: 32px 0 38px; }
  .hexagram-grid { grid-template-columns: 1fr; gap: 18px; }
  .change-arrow { min-height: 45px; transform: rotate(90deg); }
  .hexagram-card { padding: 30px; }
  .record-editor-heading { align-items: start; flex-direction: column; gap: 12px; }
  .record-fields { grid-template-columns: minmax(0, 1fr); }
  .record-actions { align-items: stretch; flex-direction: column; }
  .record-actions .primary-button { width: 100%; }
  .history-card { grid-template-columns: 1fr; gap: 12px; padding: 22px; }
  .history-card button { justify-self: start; }
  .detail-buttons { align-items: stretch; flex-direction: column-reverse; }
  .detail-buttons .primary-button { width: 100%; }
  footer { flex-direction: column; justify-content: center; gap: 2px; }
  .footer-meta { flex-direction: column; gap: 0; }
  #app-version { padding-left: 0; border-left: 0; }
}

@media (max-width: 640px) {
  .prompt-copy-actions { align-items: stretch; flex-direction: column; }
  .secondary-button { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
}