/* =============================================
   素数点描 — prime_dot_art.css
   国語辞典世界観
   ============================================= */

:root {
  --clr-paper:       #f0e8cc;
  --clr-paper-dk:    #e4d8b0;
  --clr-paper-deep:  #d8cb98;
  --clr-ink:         #1a120a;
  --clr-ink-mid:     #3a2c18;
  --clr-ink-light:   #6b5538;
  --clr-vermilion:   #c0392b;
  --clr-cobalt:      #1a4a7a;
  --clr-cobalt-lt:   rgba(26,74,122,0.1);
  --clr-gold:        #9a7a32;
  --clr-rule:        #c0a870;
  --clr-rule-lt:     #d8c898;
  --clr-muted:       #a08060;

  --font-m: 'Noto Serif JP', 'Yu Mincho', 'Hiragino Mincho ProN', serif;
  --font-e: 'Libre Baskerville', Georgia, serif;

  --ease-book: cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

/* ─── Reset ─── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; }

body {
  font-family: var(--font-m);
  background-color: var(--clr-paper);
  color: var(--clr-ink);
  min-height: 100svh;
  overflow-x: hidden;
  position: relative;
}

/* ─── 横罫線テクスチャ ─── */
.paper-lines {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    to bottom,
    transparent,
    transparent 27px,
    rgba(139,110,60,0.08) 27px,
    rgba(139,110,60,0.08) 28px
  );
  background-size: 100% 28px;
}

/* ─── ヘッダー ─── */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--clr-ink);
  border-bottom: 3px solid var(--clr-vermilion);
  padding: clamp(0.55rem, 1.5vw, 0.9rem) clamp(1rem, 4vw, 2rem);
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 1rem;
  box-shadow: 0 3px 14px rgba(0,0,0,0.28);
}

.header-center {
  text-align: center;
}
.header-center h1 {
  font-size: clamp(0.88rem, 2.2vw, 1.15rem);
  font-weight: 700;
  color: var(--clr-paper);
  letter-spacing: 0.2em;
  margin-bottom: 0.1rem;
}
.header-sub {
  font-family: var(--font-e);
  font-style: italic;
  font-size: clamp(0.55rem, 1vw, 0.65rem);
  color: var(--clr-rule);
  letter-spacing: 0.1em;
}

.home-btn {
  font-size: clamp(0.6rem, 1.1vw, 0.7rem);
  color: var(--clr-rule);
  text-decoration: none;
  border: 1px solid var(--clr-rule);
  border-radius: 2rem;
  padding: 0.28em 0.75em;
  white-space: nowrap;
  transition: background 0.18s, color 0.18s;
  letter-spacing: 0.06em;
}
.home-btn:hover { background: var(--clr-rule); color: var(--clr-ink); }

/* ─── メイン・レイアウト ─── */
main {
  position: relative;
  z-index: 1;
  padding: clamp(0.85rem, 2.5vw, 1.5rem) clamp(0.75rem, 3vw, 1.5rem);
  max-width: 80rem;
  margin: 0 auto;
}

.layout {
  display: grid;
  grid-template-columns: 17rem 1fr;
  gap: 1.1rem;
  align-items: start;
}

/* ─── パネル ─── */
.panel {
  background: var(--clr-paper-dk);
  border: 1px solid var(--clr-rule);
  display: flex;
  flex-direction: column;
  gap: 0;
  /* スティッキー（キャンバスより長くなった場合にスクロールさせる） */
  position: sticky;
  top: calc(2.5rem + 3px + 0.85rem);
  max-height: calc(100svh - 5rem);
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--clr-rule) transparent;
}

.panel-section {
  padding: 0.75rem 0.85rem;
  border-bottom: 1px solid var(--clr-rule-lt);
}
.panel-section:last-of-type {
  border-bottom: none;
}

/* ─── セクションタイトル ─── */
.sec-title {
  font-size: clamp(0.58rem, 1vw, 0.65rem);
  font-weight: 700;
  color: var(--clr-gold);
  letter-spacing: 0.25em;
  text-transform: uppercase;
  margin-bottom: 0.55rem;
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
}
.sec-note {
  font-size: 0.55rem;
  color: var(--clr-muted);
  font-weight: 400;
  letter-spacing: 0.06em;
  text-transform: none;
}

/* ─── コントロール行 ─── */
.ctrl-row {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  margin-bottom: 0.6rem;
}
.ctrl-row:last-child { margin-bottom: 0; }

.ctrl-label {
  font-size: clamp(0.65rem, 1.1vw, 0.72rem);
  color: var(--clr-ink-mid);
  display: flex;
  align-items: baseline;
  gap: 0.35rem;
  letter-spacing: 0.04em;
}
.ctrl-val {
  color: var(--clr-cobalt);
  font-family: var(--font-e);
  font-weight: 700;
}
.ctrl-unit {
  font-size: 0.6em;
  color: var(--clr-muted);
}

input[type="range"] {
  width: 100%;
  accent-color: var(--clr-cobalt);
  height: 3px;
}

/* ─── ルールヘッダー ─── */
.rules-header {
  display: grid;
  grid-template-columns: 1fr 2.5rem 5rem;
  gap: 0.4rem;
  padding: 0 0.2rem;
  margin-bottom: 0.3rem;
}
.rules-header .rh-check { /* opt-row用：チェックボックス列 */ }

.opt-row + .rules-header,
.rules-header:has(+ .opt-row) {
  grid-template-columns: 1.2rem 1fr 2.5rem 5rem;
}

.rh-cond, .rh-color, .rh-dir, .rh-check {
  font-size: 0.55rem;
  color: var(--clr-muted);
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

/* ─── ルール行（基本） ─── */
.rule-row {
  display: grid;
  grid-template-columns: 1fr 2.5rem 5rem;
  gap: 0.4rem;
  align-items: center;
  margin-bottom: 0.35rem;
  padding: 0.4rem 0.5rem;
  background: var(--clr-paper);
  border: 1px solid var(--clr-rule-lt);
  border-left: 3px solid var(--clr-rule);
}
.rule-row:last-child { margin-bottom: 0; }

/* ─── ルール行（オプション） ─── */
.opt-row {
  display: grid;
  grid-template-columns: 1.2rem 1fr 2.5rem 5rem;
  gap: 0.4rem;
  align-items: center;
  margin-bottom: 0.35rem;
  padding: 0.4rem 0.5rem;
  background: var(--clr-paper);
  border: 1px solid var(--clr-rule-lt);
  border-left: 3px solid var(--clr-rule-lt);
  opacity: 0.45;
  transition: opacity 0.18s var(--ease-book), border-left-color 0.18s;
}
.opt-row.active {
  opacity: 1;
  border-left-color: var(--clr-cobalt);
}
.opt-row:last-child { margin-bottom: 0; }

/* ─── ラベル・入力 ─── */
.rule-label {
  font-size: clamp(0.6rem, 1vw, 0.7rem);
  color: var(--clr-ink-mid);
  letter-spacing: 0.04em;
  line-height: 1.3;
}

select {
  font-size: clamp(0.6rem, 1vw, 0.68rem);
  font-family: var(--font-m);
  border: 1px solid var(--clr-rule);
  border-radius: 2px;
  padding: 0.22rem 0.35rem;
  background: var(--clr-paper);
  color: var(--clr-ink-mid);
  cursor: pointer;
  width: 100%;
  outline: none;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%23a08060' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.35rem center;
  background-size: 0.55rem;
  background-color: var(--clr-paper);
}
select:focus {
  border-color: var(--clr-cobalt);
  box-shadow: 0 0 0 2px var(--clr-cobalt-lt);
}

input[type="color"] {
  width: 2.2rem;
  height: 1.7rem;
  border: 1px solid var(--clr-rule);
  border-radius: 2px;
  cursor: pointer;
  padding: 1px;
  background: var(--clr-paper);
}

input[type="checkbox"] {
  width: 1rem;
  height: 1rem;
  cursor: pointer;
  accent-color: var(--clr-cobalt);
  border-radius: 2px;
}

/* ─── アクションボタン ─── */
.action-row {
  display: flex;
  gap: 0.45rem;
  padding: 0.75rem 0.85rem;
  border-top: 1px solid var(--clr-rule-lt);
}

.btn {
  flex: 1;
  padding: 0.45rem 0;
  border-radius: 2px;
  font-family: var(--font-m);
  font-size: clamp(0.68rem, 1.2vw, 0.78rem);
  font-weight: 700;
  cursor: pointer;
  letter-spacing: 0.1em;
  transition: opacity 0.18s, transform 0.12s;
  border: none;
}
.btn:hover  { opacity: 0.85; }
.btn:active { transform: scale(0.97); }

.btn-primary   { background: var(--clr-cobalt); color: var(--clr-paper); }
.btn-secondary {
  background: transparent;
  color: var(--clr-muted);
  border: 1px solid var(--clr-rule);
}
.btn-secondary:hover { background: var(--clr-paper-deep); color: var(--clr-ink-mid); opacity: 1; }

/* ─── 進捗・情報 ─── */
.prog {
  display: none;
  padding: 0.4rem 0.85rem;
  font-size: clamp(0.6rem, 1vw, 0.7rem);
  color: var(--clr-cobalt);
  font-family: var(--font-e);
  font-style: italic;
  letter-spacing: 0.06em;
  border-top: 1px solid var(--clr-rule-lt);
}

.info {
  padding: 0.5rem 0.85rem;
  font-size: clamp(0.58rem, 0.95vw, 0.65rem);
  color: var(--clr-ink-light);
  line-height: 2;
  letter-spacing: 0.04em;
  border-top: 1px solid var(--clr-rule-lt);
}
.info:empty { display: none; }

/* ─── キャンバス領域 ─── */
.canvas-wrap {
  position: sticky;
  top: calc(2.5rem + 3px + 0.85rem);
}

#c {
  display: block;
  width: 100%;
  border: 1px solid var(--clr-rule);
  /* キャンバス背景は古紙色（JS側でも設定するが念のため） */
  background: var(--clr-paper);
}

/* ─── レスポンシブ ─── */
@media (max-width: 860px) {
  .layout {
    grid-template-columns: 1fr;
  }
  .panel {
    position: static;
    max-height: none;
  }
  .canvas-wrap {
    position: static;
  }
}

@media (max-width: 540px) {
  header {
    grid-template-columns: 1fr;
    gap: 0.3rem;
    text-align: center;
  }
  .home-btn { justify-self: start; }
}

/* ─── Focus ─── */
:focus-visible {
  outline: 2px solid var(--clr-cobalt);
  outline-offset: 2px;
}

/* ─── Reduced Motion ─── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}