/*
  『九十九の庭』 静的読書ページ
  GitHub Pagesでは、この index.html / style.css / script.js を同じ階層に置けば動作します。
*/

:root {
  --paper: #eeeeee;
  --paper-deep: #eee3d2;
  --ink: #2f2a24;
  --muted: #837765;
  --gold: #aa8e33;
  --line: rgba(63, 52, 39, 0.18);
  --shadow: rgba(47, 42, 36, 0.16);
  --button-bg: rgba(255, 252, 245, 0.82);
  --button-bg-hover: rgba(255, 252, 245, 1);
  --font-serif: "Hiragino Mincho ProN", "Yu Mincho", "YuMincho", "Noto Serif JP", serif;
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  color-scheme: light;
  background: var(--paper);
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(255,255,255,0.45), transparent 32rem),
    linear-gradient(180deg, var(--paper), var(--paper-deep));
  font-family: var(--font-serif);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.28;
  background-image:
    linear-gradient(rgba(47, 42, 36, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(47, 42, 36, 0.025) 1px, transparent 1px);
  background-size: 34px 34px;
  mix-blend-mode: multiply;
}

.site-header {
  position: relative;
  z-index: 1;
  max-width: 70rem;
  margin: 0 auto;
  padding: clamp(2rem, 5vw, 4.5rem) 1.25rem 1.25rem;
  text-align: center;
}

.site-kicker {
  margin: 0 0 0.65rem;
  color: var(--muted);
  font-family: var(--font-sans);
  font-size: 0.78rem;
  letter-spacing: 0.22em;
}

.site-title {
  margin: 0;
  font-weight: 500;
  font-size: clamp(2rem, 5vw, 3.8rem);
  letter-spacing: 0.2em;
}

.reading-controls {
  margin-top: 1.4rem;
}

.mode-button {
  appearance: none;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.72rem 1.15rem;
  color: var(--ink);
  background: var(--button-bg);
  box-shadow: 0 0.35rem 1rem rgba(47, 42, 36, 0.07);
  font-family: var(--font-sans);
  font-size: 0.9rem;
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: background 160ms ease, transform 160ms ease, box-shadow 160ms ease;
}

.mode-button:hover {
  background: var(--button-bg-hover);
  transform: translateY(-1px);
  box-shadow: 0 0.55rem 1.25rem rgba(47, 42, 36, 0.1);
}

.mode-button:focus-visible {
  outline: 3px solid rgba(170, 142, 51, 0.38);
  outline-offset: 4px;
}

.page-shell {
  position: relative;
  z-index: 1;
  width: min(100%, 78rem);
  margin: 0 auto;
  padding: 0 1.25rem clamp(3rem, 8vw, 6rem);
}

.reader {
  margin: clamp(1.5rem, 4vw, 3rem) auto;
  color: var(--ink);
  font-size: clamp(1.02rem, 1.8vw, 1.16rem);
}

.reader--horizontal {
  max-width: 43rem;
  line-height: 2.12;
  letter-spacing: 0.035em;
}

.reader--vertical {
  width: min(100%, 70rem);
  height: min(74vh, 42rem);
  overflow-x: auto;
  overflow-y: hidden;
  padding: 1.2rem 0.25rem 1.6rem;
  writing-mode: vertical-rl;
  text-orientation: mixed;
  line-height: 2.15;
  letter-spacing: 0.08em;
  scrollbar-width: thin;
  scrollbar-color: rgba(63, 52, 39, 0.36) transparent;
}

.reader--vertical::-webkit-scrollbar {
  height: 0.65rem;
}

.reader--vertical::-webkit-scrollbar-track {
  background: transparent;
}

.reader--vertical::-webkit-scrollbar-thumb {
  background: rgba(63, 52, 39, 0.28);
  border-radius: 999px;
}

.novel-title {
  margin: 0 0 2.4em;
  font-size: 1.38em;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-align: center;
}

.reader--vertical .novel-title {
  margin: 0 0 0 2.2em;
  text-align: start;
}

.novel-paragraph {
  margin: 0 0 1.45em;
  white-space: normal;
}

.reader--vertical .novel-paragraph {
  margin: 0 0 0 1.45em;
}

.reader--vertical .novel-paragraph:last-child,
.reader--horizontal .novel-paragraph:last-child {
  margin-bottom: 0;
}

.novel-end {
  margin-top: 3em;
  text-align: center;
  color: var(--muted);
  letter-spacing: 0.22em;
}

.reader--vertical .novel-end {
  margin-top: 0;
  margin-right: 2.6em;
  text-align: start;
}

ruby {
  ruby-position: over;
}

rt {
  font-size: 0.5em;
  color: var(--muted);
  line-height: 1;
  letter-spacing: 0.04em;
}

.art-frame {
  width: min(100%, 58rem);
  margin: clamp(1.6rem, 4.5vw, 3.6rem) auto;
  padding: 0;
}

.art-frame img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: 1.4rem;
  background: rgba(255, 252, 245, 0.45);
  box-shadow: 0 1.6rem 4rem rgba(47, 42, 36, 0.1);
}

.art-frame figcaption {
  margin-top: 0.85rem;
  color: var(--muted);
  font-family: var(--font-sans);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-align: center;
}

.site-footer {
  position: relative;
  z-index: 1;
  padding: 0 1.25rem 2rem;
  color: var(--muted);
  font-family: var(--font-sans);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-align: center;
}

@media (max-width: 720px) {
  .site-title {
    letter-spacing: 0.14em;
  }

  .reader--vertical {
    height: 72vh;
    font-size: 1rem;
    line-height: 2;
  }

  .reader--horizontal {
    line-height: 2.05;
  }

  .art-frame img {
    border-radius: 1rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .mode-button {
    transition: none;
  }

  .mode-button:hover {
    transform: none;
  }
}