/* ============================================================
   Study Density Log — Apple系（ライト / ダークは端末に追従）
   色・書体はすべてここの変数を通す
   ============================================================ */
:root {
  color-scheme: light dark;
  --bg: #F5F5F7;          /* ベース（背景） */
  --surface: #FFFFFF;     /* 面 */
  --field: #F5F5F7;       /* 面の上の入力欄 */
  --ink: #1D1D1F;         /* 文字・主 */
  --muted: #6E6E73;       /* 文字・副 */
  --line: rgba(29, 29, 31, 0.10);
  --accent: #007AFF;      /* 操作・選択 */
  --accent-ink: #FFFFFF;
  --accent-soft: rgba(0, 122, 255, 0.12);
  --danger: #FF3B30;
  --self: #FF9500;        /* 自習の印 */
  --bar-rest: rgba(29, 29, 31, 0.14);
  --heat-1: #8ABAFD; --heat-ink-1: #000000;
  --heat-2: #66A6FE; --heat-ink-2: #000000;
  --heat-3: #4091FD; --heat-ink-3: #000000;
  --heat-4: #187CF4; --heat-ink-4: #000000;
  --heat-5: #0369DA; --heat-ink-5: #FFFFFF;
  --heat-6: #0159BA; --heat-ink-6: #FFFFFF;
  --heat-7: #00499C; --heat-ink-7: #FFFFFF;
  --heat-8: #003A7F; --heat-ink-8: #FFFFFF;
  --heat-9: #002B63; --heat-ink-9: #FFFFFF;
  --heat-edge: rgba(138, 186, 253, 0.45);
  /* 1日の学習時間の色：青一色の濃淡。少ない日ほど明るい青、多い日ほど黒っぽい紺。ライトもダークも同じ */

  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;

  --fs-cap: 13px;
  --fs-body: 16px;
  --fs-title: 20px;
  --fs-large: 28px;
  --fs-hero: 48px;

  --r-surface: 20px;
  --r-field: 12px;
  --r-pill: 980px;

  --content-max: 720px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #000000;
    --surface: #1C1C1E;
    --field: #2C2C2E;
    --ink: #F5F5F7;
    --muted: #98989D;
    --line: rgba(245, 245, 247, 0.12);
    --accent: #0A84FF;
    --accent-soft: rgba(10, 132, 255, 0.20);
    --danger: #FF6961;
    --self: #FFB340;
    --bar-rest: rgba(245, 245, 247, 0.18);
    --heat-1: #8ABAFD; --heat-ink-1: #000000;
    --heat-2: #66A6FE; --heat-ink-2: #000000;
    --heat-3: #4091FD; --heat-ink-3: #000000;
    --heat-4: #187CF4; --heat-ink-4: #000000;
    --heat-5: #0369DA; --heat-ink-5: #FFFFFF;
    --heat-6: #0159BA; --heat-ink-6: #FFFFFF;
    --heat-7: #00499C; --heat-ink-7: #FFFFFF;
    --heat-8: #003A7F; --heat-ink-8: #FFFFFF;
    --heat-9: #002B63; --heat-ink-9: #FFFFFF;
  }
}
:root[data-theme="dark"] {
  --bg: #000000;
  --surface: #1C1C1E;
  --field: #2C2C2E;
  --ink: #F5F5F7;
  --muted: #98989D;
  --line: rgba(245, 245, 247, 0.12);
  --accent: #0A84FF;
  --accent-soft: rgba(10, 132, 255, 0.20);
  --danger: #FF6961;
  --self: #FFB340;
  --bar-rest: rgba(245, 245, 247, 0.18);
  --heat-1: #8ABAFD; --heat-ink-1: #000000;
  --heat-2: #66A6FE; --heat-ink-2: #000000;
  --heat-3: #4091FD; --heat-ink-3: #000000;
  --heat-4: #187CF4; --heat-ink-4: #000000;
  --heat-5: #0369DA; --heat-ink-5: #FFFFFF;
  --heat-6: #0159BA; --heat-ink-6: #FFFFFF;
  --heat-7: #00499C; --heat-ink-7: #FFFFFF;
  --heat-8: #003A7F; --heat-ink-8: #FFFFFF;
  --heat-9: #002B63; --heat-ink-9: #FFFFFF;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  overflow-x: clip;
  background: var(--bg);
}

body {
  margin: 0;
  overflow-x: clip;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: var(--fs-body);
  line-height: 1.6;
  letter-spacing: 0.02em;
  min-width: 320px;
  -webkit-tap-highlight-color: transparent;
  caret-color: var(--accent);
}
::selection { background: var(--accent-soft); color: var(--ink); }

h1, h2, h3, h4 { margin: 0; font-weight: 700; line-height: 1.3; letter-spacing: 0.01em; }
h2 { font-size: var(--fs-title); }
h3 { font-size: var(--fs-body); }
h4 { font-size: var(--fs-body); font-weight: 600; }

.tabnum { font-variant-numeric: tabular-nums; }
.muted, .small { color: var(--muted); font-size: var(--fs-cap); line-height: 1.5; }

/* ---------- ヘッダー ---------- */
.app-header {
  position: sticky;
  top: 0;
  z-index: 10;
  padding-top: env(safe-area-inset-top);
  background: var(--bg);
}
.app-header-inner {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 12px 16px 8px;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
}
.sync-status { color: var(--muted); font-size: var(--fs-cap); flex: none; }
.loading-dots { display: inline-block; width: 1.5em; text-align: left; }
h1 {
  font-size: var(--fs-large);
  font-weight: 700;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ---------- ログイン前 ---------- */
.signed-out {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 24px 16px;
}
.signed-out .surface { display: grid; gap: 16px; justify-items: start; }

/* ---------- レイアウト ---------- */
.app {
  padding: 8px 16px calc(112px + env(safe-area-inset-bottom));
  max-width: var(--content-max);
  margin: 0 auto;
}
@media (min-width: 720px) {
  .app-header-inner, .app, .signed-out { padding-left: 24px; padding-right: 24px; }
}
.screen { display: none; }
.screen.active { display: block; }

/* ---------- 面 ---------- */
.surface, .card {
  background: var(--surface);
  border-radius: var(--r-surface);
  padding: 20px;
  margin-bottom: 16px;
  min-width: 0;
}
.surface-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}
.surface-head > :first-child { min-width: 0; }
.surface-head .muted { flex: none; }
.stack { display: grid; gap: 12px; }
.group-title {
  color: var(--muted);
  font-size: var(--fs-cap);
  font-weight: 400;
  margin: 24px 4px 8px;
}
.group-title:first-child { margin-top: 0; }

/* ---------- ホーム：今日 ---------- */
.hero-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0 12px;
  color: var(--muted);
  font-size: var(--fs-cap);
  font-variant-numeric: tabular-nums;
}
.hero-main {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px;
  margin: 12px 0 20px;
}
.hero-meta span { white-space: nowrap; }
.hero-label { font-size: var(--fs-cap); color: var(--muted); font-weight: 600; }
.hero-value {
  font-size: var(--fs-hero);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.01em;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}
.hero-value .unit, .hero-streak-value .unit {
  font-size: var(--fs-title);
  font-weight: 600;
  letter-spacing: 0.02em;
  margin: 0 2px;
}
.hero-sub { color: var(--muted); font-size: var(--fs-cap); margin-top: 4px; font-variant-numeric: tabular-nums; }
.hero-streak { text-align: right; flex: none; }
.hero-streak-value {
  font-size: var(--fs-large);
  font-weight: 700;
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
}
.hero-streak.zero .hero-streak-value { color: var(--muted); }
.streak-broken { color: var(--muted); font-size: var(--fs-cap); margin: -8px 0 16px; }
.hero-row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  font-size: var(--fs-cap);
  color: var(--muted);
  padding-top: 12px;
  border-top: 1px solid var(--line);
  margin-top: 16px;
}
.hero-row b { color: var(--ink); font-weight: 600; }

/* 進み具合 */
.meter-row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  font-size: var(--fs-cap);
  color: var(--muted);
  margin-bottom: 8px;
  font-variant-numeric: tabular-nums;
}
.meter-row b { color: var(--ink); font-weight: 600; }
.progress {
  height: 8px;
  background: var(--field);
  border-radius: var(--r-pill);
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  width: 100%;
  background: var(--accent);
  border-radius: var(--r-pill);
  transform-origin: left center;
}

/* 期間の合計 */
.total-row {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 12px 0;
  border-top: 1px solid var(--line);
  font-variant-numeric: tabular-nums;
}
.total-row:first-child { border-top: 0; padding-top: 0; }
.total-row:last-child { padding-bottom: 0; }
.total-row .name { width: 48px; flex: none; color: var(--muted); font-size: var(--fs-cap); font-weight: 600; }
.total-row .value { font-size: var(--fs-title); font-weight: 700; white-space: nowrap; }
.total-row .muted { margin-left: auto; white-space: nowrap; }

/* ---------- 棒グラフ ---------- */
.chart-readout {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 12px;
  font-variant-numeric: tabular-nums;
  min-height: 32px;
}
.chart-readout b { font-size: var(--fs-title); font-weight: 700; }
.chart-readout .muted { font-size: var(--fs-cap); }
.bars {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 8px;
  height: 128px;
  align-items: end;
}
.bar-btn {
  height: 100%;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
  border-radius: 8px;
  min-width: 0;
}
.bar {
  width: 100%;
  max-width: 40px;
  min-height: 3px;
  background: var(--bar-rest);
  border-radius: 6px 6px 2px 2px;
  transition: background-color 0.15s ease;
}
.bar-btn[aria-pressed="true"] .bar { background: var(--accent); }
.bar-labels {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 8px;
  margin-top: 8px;
  text-align: center;
  font-size: var(--fs-cap);
  color: var(--muted);
}
.bar-labels .is-selected { color: var(--ink); font-weight: 600; }

/* 内訳 */
.legend-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  font-size: var(--fs-cap);
  padding: 8px 0;
  color: var(--muted);
  border-top: 1px solid var(--line);
  font-variant-numeric: tabular-nums;
}
.legend-row:first-of-type, .surface-head + .legend-row { border-top: 0; }
.legend-row span { min-width: 0; }
.legend-row span:first-child { color: var(--ink); overflow-wrap: anywhere; }
.legend-row span:last-child { text-align: right; flex: none; }

/* ---------- ボタン ---------- */
.btn {
  appearance: none;
  border: 0;
  background: var(--field);
  color: var(--accent);
  border-radius: var(--r-pill);
  padding: 10px 20px;
  min-height: 44px;
  font: inherit;
  font-size: var(--fs-body);
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
  touch-action: manipulation;
  transition: background-color 0.15s ease, color 0.15s ease, opacity 0.15s ease, transform 0.08s ease;
}
.btn:hover { background: var(--accent-soft); }
.btn:active { transform: scale(0.98); }
.btn.small { min-height: 36px; padding: 6px 16px; font-size: var(--fs-cap); }
.btn.primary { background: var(--accent); color: var(--accent-ink); }
.btn.primary:hover { opacity: 0.9; }
.btn.danger { color: var(--danger); }
.btn.block { width: 100%; }
.btn[disabled] { opacity: 0.4; cursor: default; transform: none; }
.btn[disabled]:hover { background: var(--field); }
.btn.primary[disabled]:hover { background: var(--accent); opacity: 0.4; }

.link-btn {
  appearance: none;
  background: none;
  border: 0;
  color: var(--accent);
  font: inherit;
  font-size: var(--fs-cap);
  font-weight: 600;
  padding: 8px 4px;
  min-height: 36px;
  cursor: pointer;
  border-radius: 8px;
}
.link-btn.danger { color: var(--danger); }
.link-btn:hover { text-decoration: underline; }

.back-btn {
  appearance: none;
  background: none;
  border: 0;
  color: var(--accent);
  font: inherit;
  font-size: var(--fs-body);
  padding: 8px 0;
  margin-bottom: 8px;
  min-height: 44px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.back-btn svg { width: 18px; height: 18px; }

/* ---------- フォーム ---------- */
input, select, textarea {
  width: 100%;
  max-width: 100%;
  background: var(--field);
  color: var(--ink);
  border: 1px solid transparent;
  border-radius: var(--r-field);
  padding: 10px 12px;
  min-height: 44px;
  font-family: inherit;
  font-size: var(--fs-body);
  min-width: 0;
  display: block;
  transition: border-color 0.15s ease;
}
input::placeholder, textarea::placeholder { color: var(--muted); }
select { overflow: hidden; text-overflow: ellipsis; }
input[type="date"],
input[type="time"] { -webkit-appearance: none; appearance: none; }
input[type="date"]::-webkit-date-and-time-value,
input[type="time"]::-webkit-date-and-time-value { min-width: 0; text-align: left; }
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--accent); }
input:disabled, select:disabled { opacity: 0.5; }
input[type="file"] { padding: 10px 12px; font-size: var(--fs-cap); }
textarea { min-height: 96px; resize: vertical; line-height: 1.7; }
#taskMemoInput { min-height: 144px; }

label, .field-label {
  display: block;
  font-size: var(--fs-cap);
  font-weight: 600;
  color: var(--muted);
  margin: 0 0 4px;
}
.pair + .field, .field + .pair, .field + .field, .field + .row-2, .row-2 + .field, .row-2 + .row-2 { margin-top: 16px; }
.field-group + .field-group { margin-top: 16px; padding-top: 16px; border-top: 1px solid var(--line); }

.row { display: flex; gap: 8px; align-items: stretch; flex-wrap: wrap; min-width: 0; }
.row > * { flex: 1 1 160px; min-width: 0; }
.row > .btn, .row > button, .row > .link-btn { flex: 0 0 auto; }
.row-2 { display: flex; gap: 8px; align-items: stretch; }
.row-2 > * { flex: 1 1 0; min-width: 0; }
.col { display: flex; flex-direction: column; gap: 8px; }

/* 学習時間（時間・分） */
.duration {
  display: flex;
  align-items: center;
  gap: 8px;
}
.duration input { text-align: right; font-variant-numeric: tabular-nums; flex: 1 1 0; }
.duration span { color: var(--muted); font-size: var(--fs-cap); flex: none; }

/* スイッチ */
.switch-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 44px;
  margin: 0;
  color: var(--ink);
  font-size: var(--fs-body);
  font-weight: 400;
  cursor: pointer;
}
.switch-row input {
  appearance: none;
  -webkit-appearance: none;
  width: 51px;
  min-width: 51px;
  height: 31px;
  min-height: 31px;
  padding: 0;
  border: 0;
  border-radius: var(--r-pill);
  background: var(--bar-rest);
  position: relative;
  cursor: pointer;
  transition: background-color 0.2s ease;
}
.switch-row input::before {
  content: "";
  position: absolute;
  top: 2px;
  left: 2px;
  width: 27px;
  height: 27px;
  border-radius: 50%;
  background: #FFFFFF;
  transition: transform 0.2s ease;
}
.switch-row input:checked { background: var(--accent); }
.switch-row input:checked::before { transform: translateX(20px); }

/* 質（セグメント） */
.segmented {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(0, 1fr);
  background: var(--field);
  border-radius: var(--r-field);
  padding: 2px;
  gap: 2px;
}
.segmented label {
  margin: 0;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  border-radius: 10px;
  color: var(--ink);
  font-size: var(--fs-body);
  font-weight: 600;
  cursor: pointer;
}
.segmented input { position: absolute; opacity: 0; width: 1px; height: 1px; min-height: 0; pointer-events: none; }
.segmented label:has(input:checked) { background: var(--surface); box-shadow: 0 1px 3px rgba(0, 0, 0, 0.12); }

/* ストップウォッチ（下に小さく） */
.sw-head { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; margin-bottom: 12px; }
.sw-display { font-size: var(--fs-title); font-weight: 700; font-variant-numeric: tabular-nums; }
.sw-actions { display: flex; flex-wrap: wrap; gap: 8px; }
.sw-actions .btn { flex: 1 1 auto; padding-left: 12px; padding-right: 12px; }

/* 日付と学習時間：幅があれば横並び */
@media (min-width: 360px) {
  .date-dur { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 8px; }
  .date-dur .field + .field { margin-top: 0; }
  .pair { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 8px; }
  .pair .field + .field { margin-top: 0; }
  .date-dur .duration { gap: 4px; }
  .date-dur .duration input { padding-left: 8px; padding-right: 8px; }
}

/* 保存バー */
.save-bar {
  position: sticky;
  bottom: calc(76px + env(safe-area-inset-bottom));
  z-index: 5;
  display: flex;
  gap: 8px;
  padding: 12px 0;
  background: var(--bg);
}
.save-bar .btn { flex: 1 1 0; }

/* ---------- チップ・タグ ---------- */
.tags { display: flex; gap: 8px; flex-wrap: wrap; }
.tag {
  display: inline-block;
  background: var(--field);
  color: var(--muted);
  border-radius: var(--r-pill);
  padding: 2px 8px;
  font-size: 12px;
  font-weight: 600;
  line-height: 1.6;
}
.chip {
  appearance: none;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--ink);
  border-radius: var(--r-pill);
  padding: 6px 16px;
  font: inherit;
  font-size: var(--fs-cap);
  font-weight: 600;
  cursor: pointer;
  min-height: 36px;
  transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}
.chip.active { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }

/* ---------- 一覧の行 ---------- */
.list-item {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 12px;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
  border-top: 1px solid var(--line);
  min-width: 0;
  margin: 0;
}
.list-item:first-child, .surface-head + .list-item, h2 + .list-item, .row + .list-item { border-top: 0; }
.list-item > div, .list-item > span { min-width: 0; }
.list-item > div:only-child, .list-item > span:only-child { flex: 1; }
.list-item > span:first-child { overflow-wrap: anywhere; }
.inline-dot { display: none; }

/* タスクのチェック */
label.list-item {
  flex-wrap: nowrap;
  justify-content: flex-start;
  cursor: pointer;
  font-size: var(--fs-body);
  font-weight: 400;
  color: var(--ink);
  min-height: 52px;
}
label.list-item input[type="checkbox"] {
  appearance: none;
  -webkit-appearance: none;
  flex: none;
  width: 24px;
  min-width: 24px;
  height: 24px;
  min-height: 24px;
  padding: 0;
  margin: 0;
  border-radius: 50%;
  border: 2px solid var(--bar-rest);
  background: transparent;
  display: grid;
  place-items: center;
  cursor: pointer;
  transition: background-color 0.15s ease, border-color 0.15s ease;
}
label.list-item input[type="checkbox"]:checked { background: var(--accent); border-color: var(--accent); }
label.list-item input[type="checkbox"]:disabled { opacity: 0.4; cursor: default; }
label.list-item input[type="checkbox"]:checked::before {
  content: "";
  width: 6px;
  height: 11px;
  border: solid var(--accent-ink);
  border-width: 0 2px 2px 0;
  transform: translateY(-1px) rotate(45deg);
}
label.list-item > span:not(.tag) { flex: 1; min-width: 0; overflow-wrap: anywhere; }
label.list-item:has(input:checked) > span:not(.tag) { color: var(--muted); text-decoration: line-through; text-decoration-color: var(--muted); }
.skip-carry-external { margin-left: auto; flex: none; }

/* ---------- 設定のメニュー ---------- */
.menu { padding: 0 0 0 20px; overflow: hidden; }
.menu-row {
  appearance: none;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  background: none;
  border: 0;
  border-top: 1px solid var(--line);
  color: var(--ink);
  font: inherit;
  font-size: var(--fs-body);
  text-align: left;
  padding: 12px 20px 12px 0;
  min-height: 52px;
  cursor: pointer;
}
.menu-row:first-child { border-top: 0; }
.menu-row:hover { background: transparent; }
.menu-row .value { color: var(--muted); font-size: var(--fs-cap); margin-left: auto; text-align: right; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.menu-row .chev { width: 16px; height: 16px; flex: none; color: var(--muted); }
.menu-row.danger { color: var(--danger); justify-content: center; padding-right: 20px; }
.menu-static { cursor: default; display: block; }
.menu-static .muted { display: block; }

/* 管理画面の行の操作 */
.item-actions { display: flex; gap: 4px; flex: none; align-items: center; }
.icon-btn {
  appearance: none;
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  background: var(--field);
  color: var(--ink);
  border: 0;
  border-radius: 50%;
  cursor: pointer;
  padding: 0;
}
.icon-btn svg { width: 16px; height: 16px; }
.icon-btn[disabled] { opacity: 0.3; cursor: default; }

/* 質係数 */
.quality-grid { display: grid; gap: 0; }
.quality-grid .list-item { flex-wrap: nowrap; }
.quality-grid .list-item label { margin: 0; color: var(--ink); font-size: var(--fs-body); font-weight: 600; flex: 1; }
.quality-grid input { width: 120px; flex: none; text-align: right; font-variant-numeric: tabular-nums; }

/* ---------- タイムライン（フィード） ---------- */
.feed {
  margin: 0 -16px;
  background: var(--surface);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
@media (min-width: 720px) {
  .feed { margin: 0; border: 0; border-radius: var(--r-surface); }
}
.post {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 12px;
  padding: 12px 16px 4px;
  border-top: 1px solid var(--line);
}
.post:first-child { border-top: 0; }
.avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--field);
  color: var(--ink);
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: var(--fs-body);
}
.post-head {
  display: flex;
  align-items: baseline;
  gap: 4px 8px;
  min-width: 0;
  line-height: 1.4;
}
.post-name { font-weight: 700; flex: none; }
.post-sub { color: var(--muted); min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.post-time { color: var(--muted); font-size: var(--fs-cap); margin-left: auto; flex: none; font-variant-numeric: tabular-nums; }
.post-text { margin: 4px 0 0; white-space: pre-wrap; overflow-wrap: anywhere; line-height: 1.6; }
.post-stats {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 12px;
  margin-top: 8px;
  color: var(--muted);
  font-size: var(--fs-cap);
  font-variant-numeric: tabular-nums;
}
.post-big { color: var(--ink); font-size: var(--fs-body); font-weight: 700; }
.post { position: relative; -webkit-touch-callout: none; }
.post-more {
  appearance: none;
  background: none;
  border: 0;
  color: var(--muted);
  width: 36px;
  height: 36px;
  margin: -8px -10px -8px 0;
  border-radius: 50%;
  display: grid;
  place-items: center;
  cursor: pointer;
  padding: 0;
  flex: none;
}
.post-more svg { width: 18px; height: 18px; stroke-width: 2.5; }
.post-more:hover, .post-more[aria-expanded="true"] { color: var(--accent); background: var(--accent-soft); }
.post-more:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.post-time { margin-right: 0; }
.post-menu {
  position: absolute;
  top: 40px;
  right: 12px;
  z-index: 6;
  min-width: 160px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.16);
  padding: 4px;
}
.post-menu.up { top: auto; bottom: calc(100% - 40px); }
.post-menu button {
  appearance: none;
  width: 100%;
  display: flex;
  align-items: center;
  gap: 12px;
  background: none;
  border: 0;
  border-radius: 10px;
  color: var(--ink);
  font: inherit;
  font-size: var(--fs-body);
  padding: 10px 12px;
  min-height: 44px;
  cursor: pointer;
  text-align: left;
}
.post-menu button svg { width: 18px; height: 18px; flex: none; }
.post-menu button:hover { background: var(--field); }
.post-menu button.danger { color: var(--danger); }
.post-menu button:focus-visible { outline: 2px solid var(--accent); outline-offset: -2px; }
.post { padding-bottom: 12px; }
.empty-state { color: var(--muted); font-size: var(--fs-cap); text-align: center; padding: 32px 20px; }

/* ---------- 折りたたみ ---------- */
details.fold { margin-bottom: 16px; }
details.fold > summary {
  list-style: none;
  cursor: pointer;
  color: var(--accent);
  font-size: var(--fs-body);
  font-weight: 600;
  padding: 12px 4px;
  min-height: 44px;
  display: flex;
  align-items: center;
  gap: 8px;
  border-radius: 8px;
}
details.fold > summary::-webkit-details-marker { display: none; }
details.fold > summary::before {
  content: "";
  width: 7px;
  height: 7px;
  border: solid currentColor;
  border-width: 0 2px 2px 0;
  transform: rotate(-45deg);
  transition: transform 0.15s ease;
  flex: none;
}
details.fold[open] > summary::before { transform: rotate(45deg); }

/* ---------- カレンダー ---------- */
.cal-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 8px;
}
.cal-nav-btn {
  appearance: none;
  background: var(--field);
  border: 0;
  color: var(--accent);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  cursor: pointer;
  flex: none;
  padding: 0;
}
.cal-nav-btn svg { width: 16px; height: 16px; }
.cal-nav-label {
  appearance: none;
  background: none;
  border: 0;
  color: var(--ink);
  font: inherit;
  font-size: var(--fs-body);
  font-weight: 600;
  padding: 8px 12px;
  cursor: pointer;
  font-variant-numeric: tabular-nums;
  border-radius: 8px;
}
.cal-week, .cal-grid {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 4px;
}
.cal-week { margin: 8px 0 4px; }
.cal-week div { text-align: center; font-size: 12px; color: var(--muted); }
.cal-cell {
  appearance: none;
  aspect-ratio: 1 / 1;
  min-height: 40px;
  border: 0;
  border-radius: 10px;
  background: transparent;
  color: var(--ink);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  font: inherit;
  font-size: var(--fs-cap);
  font-variant-numeric: tabular-nums;
  cursor: pointer;
  padding: 0;
  min-width: 0;
  position: relative;
}
.cal-cell.empty { cursor: default; }
.studied-1 { background: var(--heat-1); --cell-ink: var(--heat-ink-1); }
.studied-2 { background: var(--heat-2); --cell-ink: var(--heat-ink-2); }
.studied-3 { background: var(--heat-3); --cell-ink: var(--heat-ink-3); }
.studied-4 { background: var(--heat-4); --cell-ink: var(--heat-ink-4); }
.studied-5 { background: var(--heat-5); --cell-ink: var(--heat-ink-5); }
.studied-6 { background: var(--heat-6); --cell-ink: var(--heat-ink-6); }
.studied-7 { background: var(--heat-7); --cell-ink: var(--heat-ink-7); }
.studied-8 { background: var(--heat-8); --cell-ink: var(--heat-ink-8); }
.studied-9 { background: var(--heat-9); --cell-ink: var(--heat-ink-9); }
.cal-cell[class*='studied-']:not(.studied-0) { color: var(--cell-ink); }
.cal-cell.studied-6, .cal-cell.studied-7, .cal-cell.studied-8, .cal-cell.studied-9 { font-weight: 700; }
/* 一番濃い紺は暗い画面の地に近いので、細い縁で面を見せる */
.cal-cell.studied-7, .cal-cell.studied-8, .cal-cell.studied-9 { box-shadow: inset 0 0 0 1px var(--heat-edge); }
/* 色の段階の見本：1本の帯と目盛り */
.heat-legend { display: flex; align-items: flex-end; gap: 8px; margin-top: 12px; }
.heat-bar { flex: 1; display: grid; grid-template-columns: repeat(9, minmax(0, 1fr)); gap: 2px; max-width: 360px; }
.heat-bar span { display: grid; gap: 4px; min-width: 0; }
.heat-bar i { display: block; height: 10px; border-radius: 2px; }
.heat-bar span:first-child i { border-radius: 5px 2px 2px 5px; }
.heat-bar span:last-child i { border-radius: 2px 5px 5px 2px; }
.heat-bar small, .heat-unit { font-size: 11px; color: var(--muted); font-variant-numeric: tabular-nums; line-height: 1; }
.heat-unit { flex: none; }
.cal-cell.today > span:first-child { font-weight: 700; text-decoration: underline; text-underline-offset: 3px; }
.cal-cell.in-period::after {
  content: "";
  position: absolute;
  left: 25%;
  right: 25%;
  bottom: 4px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  opacity: 0.5;
}
.cal-cell.selected { box-shadow: inset 0 0 0 2px var(--ink); }
.cal-cell small { font-size: 10px; line-height: 1; min-height: 10px; }
.cal-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 16px;
  margin-top: 12px;
  font-size: var(--fs-cap);
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}
.cal-legend b { color: var(--ink); font-weight: 600; }
.in-period-dot {
  display: inline-block;
  width: 12px;
  height: 2px;
  border-radius: 2px;
  background: var(--muted);
  vertical-align: middle;
  margin-right: 4px;
}
#calDayRecords:not(:empty) { margin-top: 16px; padding-top: 16px; border-top: 1px solid var(--line); }
#calDayRecords h4 { margin-bottom: 4px; }

/* ---------- 下のナビ ---------- */
.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 10;
  background: var(--surface);
  border-top: 1px solid var(--line);
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 144px));
  justify-content: center;
  padding: 4px 4px calc(4px + env(safe-area-inset-bottom));
}
.bottom-nav button {
  appearance: none;
  background: none;
  color: var(--muted);
  border: 0;
  padding: 6px 2px;
  min-height: 52px;
  font: inherit;
  font-size: 11px;
  font-weight: 600;
  white-space: nowrap;
  letter-spacing: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  cursor: pointer;
  border-radius: 10px;
  min-width: 0;
  transition: color 0.15s ease;
}
.bottom-nav button svg {
  width: 24px;
  height: 24px;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
  pointer-events: none;
}
.bottom-nav button.active { color: var(--accent); }

/* 線アイコン共通 */
.ico { fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }

/* ---------- フォーカス ---------- */
.btn:focus-visible,
.chip:focus-visible,
.link-btn:focus-visible,
.back-btn:focus-visible,
.icon-btn:focus-visible,
.menu-row:focus-visible,
.cal-nav-btn:focus-visible,
.cal-nav-label:focus-visible,
.cal-cell:focus-visible,
.bar-btn:focus-visible,
.bottom-nav button:focus-visible,
details.fold > summary:focus-visible,
.switch-row input:focus-visible,
label.list-item:has(input:focus-visible),
.segmented label:has(input:focus-visible) {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}

@media (max-width: 380px) {
  :root { --fs-hero: 40px; }
  .bottom-nav button { font-size: 10px; }
  .surface, .card { padding: 16px; }
  .menu { padding-left: 16px; }
  .menu-row { padding-right: 16px; }
}

/* ---------- 教科の色（タイムライン） ---------- */
:root { --tint: 12%; --avatar-ink: #000000; } /* 色を塗った丸の文字は、ライトでもダークでも黒 */
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) { --tint: 16%; } }
:root[data-theme="dark"] { --tint: 16%; }
/* 背景は面の色に少しだけ混ぜる。暗い画面でも鮮やかな色でベタ塗りしない */
.post.tinted { background: color-mix(in srgb, var(--c) var(--tint), var(--surface)); }
.post.tinted .avatar, .avatar.filled { background: var(--c); color: var(--avatar-ink); }
@media (min-width: 720px) {
  .post:first-child { border-top-left-radius: var(--r-surface); border-top-right-radius: var(--r-surface); }
  .post:last-child { border-bottom-left-radius: var(--r-surface); border-bottom-right-radius: var(--r-surface); }
}

/* 設定：タイムラインの色 */
.color-item + .color-item .color-row { border-top: 1px solid var(--line); }
.color-row { gap: 12px; }
.color-row > span:nth-child(2) { flex: 1; min-width: 0; }
.avatar.small { width: 32px; height: 32px; font-size: var(--fs-cap); flex: none; }
.color-row .value { margin-left: 0; }
.color-panel { padding: 4px 20px 16px 44px; }
.swatches {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(40px, 1fr));
  gap: 8px;
  max-width: 400px;
}
.swatch {
  appearance: none;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 0;
  padding: 0;
  background: var(--c);
  cursor: pointer;
  justify-self: center;
}
.swatch[aria-pressed="true"] { box-shadow: 0 0 0 2px var(--surface), 0 0 0 4px var(--ink); }
.swatch.none {
  background: linear-gradient(135deg, transparent calc(50% - 1px), var(--muted) calc(50% - 1px), var(--muted) calc(50% + 1px), transparent calc(50% + 1px)), var(--field);
}
.swatch:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
.custom-color {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin: 16px 0 0;
  max-width: 400px;
  color: var(--ink);
  font-size: var(--fs-body);
  font-weight: 400;
}
.custom-color input[type="color"] {
  width: 64px;
  min-width: 64px;
  height: 36px;
  min-height: 36px;
  padding: 2px;
  border-radius: var(--r-field);
  cursor: pointer;
}
@media (max-width: 380px) { .color-panel { padding-left: 16px; padding-right: 16px; } }