:root {
  --bg: #ffffff;
  --fg: #16181d;
  --muted: #6b7280;
  --line: #e5e7eb;
  --panel: #ffffff;
  --accent: #111827;
  --accent-fg: #ffffff;
  --danger: #dc2626;
  --shadow: 0 10px 30px rgba(0, 0, 0, .14);
  --fab: 56px;
  color-scheme: light;
}

html[data-theme="dark"] {
  --bg: #0f1115;
  --fg: #e8eaed;
  --muted: #9aa1ac;
  --line: #2a2f3a;
  --panel: #171a21;
  --accent: #e8eaed;
  --accent-fg: #0f1115;
  --danger: #f87171;
  --shadow: 0 10px 30px rgba(0, 0, 0, .5);
  color-scheme: dark;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: var(--bg);
  color: var(--fg);
  font-family: system-ui, "Hiragino Sans", sans-serif;
  overscroll-behavior: none;
  -webkit-text-size-adjust: 100%;
}

#sheet {
  position: relative;
  min-height: 100%;
  width: 100%;
}

#text {
  display: block;
  /* 描画面が画面より広がっても、文字は画面幅のまま読めるようにする */
  width: min(100%, 100vw);
  min-height: 100vh;
  margin: 0;
  border: 0;
  outline: none;
  resize: none;
  overflow: hidden;
  background: transparent;
  color: inherit;
  padding: max(20px, env(safe-area-inset-top)) 20px calc(var(--fab) + 48px) 20px;
  font-family: var(--memo-font, system-ui);
  font-size: var(--memo-size, 16px);
  line-height: 1.7;
  caret-color: var(--fg);
}

#text::placeholder { color: var(--muted); opacity: .55; }

#board {
  position: absolute;
  top: 0;
  left: 0;
  pointer-events: none;
  touch-action: auto;
}

body[data-mode="pen"] #board,
body[data-mode="eraser"] #board {
  pointer-events: auto;
  touch-action: none;
  cursor: crosshair;
}

body[data-mode="pen"] #text,
body[data-mode="eraser"] #text { caret-color: transparent; }

#fab {
  position: fixed;
  right: max(16px, env(safe-area-inset-right));
  bottom: max(16px, env(safe-area-inset-bottom));
  width: var(--fab);
  height: var(--fab);
  border: 0;
  border-radius: 50%;
  background: var(--accent);
  color: var(--accent-fg);
  box-shadow: var(--shadow);
  display: grid;
  place-items: center;
  cursor: pointer;
  z-index: 40;
  transition: transform .18s ease;
}

#fab:active { transform: scale(.94); }
#fab svg { width: 22px; height: 22px; fill: currentColor; }

#scrim {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, .28);
  z-index: 45;
}

#menu {
  position: fixed;
  right: max(16px, env(safe-area-inset-right));
  bottom: calc(var(--fab) + max(16px, env(safe-area-inset-bottom)) + 12px);
  width: min(340px, calc(100vw - 32px));
  max-height: min(70vh, 620px);
  overflow-y: auto;
  padding: 8px 14px 14px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 16px;
  box-shadow: var(--shadow);
  z-index: 50;
}

@media (max-width: 480px) {
  #menu {
    left: max(12px, env(safe-area-inset-left));
    right: max(12px, env(safe-area-inset-right));
    width: auto;
  }
}

.group { padding: 10px 0; border-bottom: 1px solid var(--line); }
.group:last-child { border-bottom: 0; }
.group h2 {
  margin: 0 0 8px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .08em;
  color: var(--muted);
}

.row { display: flex; flex-wrap: wrap; gap: 8px; }
.row.end { justify-content: flex-end; }

.seg { display: flex; gap: 6px; }
.seg button {
  flex: 1;
  padding: 9px 6px;
  font-size: 13px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: transparent;
  color: var(--fg);
  cursor: pointer;
}
.seg button[aria-checked="true"] { background: var(--accent); color: var(--accent-fg); border-color: var(--accent); }

.act {
  padding: 9px 14px;
  font-size: 13px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: transparent;
  color: var(--fg);
  cursor: pointer;
}
.act:hover:not(:disabled) { border-color: var(--accent); }
.act:disabled { opacity: .38; cursor: default; }
.act.danger { color: var(--danger); border-color: color-mix(in srgb, var(--danger) 45%, transparent); }

.swatch {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: 2px solid var(--line);
  cursor: pointer;
  padding: 0;
}
.swatch[aria-checked="true"] { outline: 2px solid var(--fg); outline-offset: 2px; }

.width-btn {
  width: 44px;
  height: 34px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: transparent;
  cursor: pointer;
}
.width-btn span { display: block; width: 22px; border-radius: 99px; background: var(--fg); }
.width-btn[aria-checked="true"] { border-color: var(--accent); background: color-mix(in srgb, var(--fg) 8%, transparent); }

.chip {
  padding: 8px 12px;
  font-size: 13px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: transparent;
  color: var(--fg);
  cursor: pointer;
}
.chip[aria-checked="true"] { background: var(--accent); color: var(--accent-fg); border-color: var(--accent); }

#confirm {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
  background: rgba(0, 0, 0, .35);
  z-index: 60;
  padding: 20px;
}
#confirm .card {
  width: min(360px, 100%);
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 20px;
  box-shadow: var(--shadow);
}
#confirm h2 { margin: 0 0 8px; font-size: 16px; }
#confirm p { margin: 0 0 16px; font-size: 13px; color: var(--muted); line-height: 1.6; }

#toast {
  position: fixed;
  left: 50%;
  bottom: calc(var(--fab) + 32px);
  transform: translate(-50%, 12px);
  padding: 10px 16px;
  border-radius: 999px;
  background: var(--accent);
  color: var(--accent-fg);
  font-size: 13px;
  box-shadow: var(--shadow);
  opacity: 0;
  pointer-events: none;
  transition: opacity .2s ease, transform .2s ease;
  z-index: 70;
}
#toast.show { opacity: 1; transform: translate(-50%, 0); }

[hidden] { display: none !important; }

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}