/* ============================================================
   にほんご友 — モックアップ共通スタイル
   デザイン指針は /DESIGN.md を参照
   ============================================================ */

:root {
  /* カラーパレット（DESIGN.md 準拠） */
  --color-bg: #f7f6f2; /* 胡粉色 */
  --color-bg-alt: #f0efea; /* 背景差分（境界表現用） */
  --color-text: #333; /* 消炭色 */
  --color-border: #e2e2e2; /* 灰汁色 */
  --color-accent: #626035; /* 鶯茶 */
  --color-highlight: #d8c3c3; /* 灰桜 */
  --color-muted: rgb(51 51 51 / 70%);

  /* タイポグラフィ */
  --font-display: 'Noto Serif JP', serif;
  --font-body: 'BIZ UDPGothic', 'Noto Sans JP', sans-serif;
  --font-utility: 'Noto Sans JP', sans-serif;

  /* 余白（スマホ向けに DESIGN.md の 120–160px から縮小） */
  --space-sm: 12px;
  --space-md: 24px;
  --space-lg: 48px;
  --space-xl: 72px;
  --transition: 0.4s ease;
}

/* -------- リセット -------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
html {
  text-size-adjust: 100%;
  font-size: 16px;
}
a {
  color: inherit;
}
button {
  font: inherit;
}

body {
  font-family: var(--font-body);
  font-weight: 400;
  color: var(--color-text);
  background-color: var(--color-bg);
  /* 行間・字間は DESIGN.md のルール */
  line-height: 1.85;
  letter-spacing: 0.06em;
  min-height: 100vh;
  /* 和紙ノイズテクスチャ（SVG 埋め込み・opacity 0.03） */
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 200 200'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/></filter><rect width='100%25' height='100%25' filter='url(%23n)' opacity='0.03'/></svg>");
}

/* -------- アプリ共通レイアウト -------- */
/* tango-shell は body 直下の縦伸び容器。ヘッダーをサイト共通幅 (720px) で見せる一方、
   学習画面本体 (.app) はモバイル幅 (480px) を維持する。 */
.tango-shell {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}
.app {
  width: 100%;
  max-width: 480px;
  margin: 0 auto;
  padding: 0 20px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.app-header {
  width: 100%;
  max-width: 720px;
  margin: 0 auto;
  padding: 24px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  border-bottom: 0.5px solid var(--color-border);
  min-height: 64px;
}

.app-header-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.05rem;
  letter-spacing: 0.22em;
  color: var(--color-text);
  text-decoration: none;
  transition: color 0.4s ease;
}
.app-header-brand:hover {
  color: var(--color-accent);
}
.app-header-brand-mark {
  display: block;
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

.app-header-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.brand {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.05rem;
  letter-spacing: 0.2em;
}

.brand-sub {
  font-family: var(--font-display);
  font-size: 0.8rem;
  letter-spacing: 0.2em;
  color: var(--color-muted);
}

/* -------- ボタン類 -------- */
.icon-button {
  width: 40px;
  height: 40px;
  background: none;
  border: 1px solid var(--color-border);
  border-radius: 2px;
  cursor: pointer;
  transition: all var(--transition);
  color: var(--color-text);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
}
.icon-button:hover {
  background: var(--color-highlight);
  border-color: var(--color-highlight);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 20px;
  font-family: var(--font-body);
  font-size: 0.9rem;
  letter-spacing: 0.1em;
  background: none;
  border: 1px solid var(--color-text);
  color: var(--color-text);
  border-radius: 2px;
  cursor: pointer;
  transition:
    background var(--transition),
    color var(--transition),
    border-color var(--transition);
  text-decoration: none;
  text-align: center;
  /* 影は使わない（DESIGN.md） */
}
.btn:hover {
  background: var(--color-text);
  color: var(--color-bg);
}

.btn-primary {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-bg);
}
.btn-primary:hover {
  background: var(--color-bg);
  color: var(--color-accent);
}
.btn-ghost {
  border-color: var(--color-border);
  color: var(--color-muted);
}
.btn-ghost:hover {
  background: var(--color-bg-alt);
  color: var(--color-text);
  border-color: var(--color-text);
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-utility);
  font-weight: 500;
  font-size: 0.78rem;
  letter-spacing: 0.28em;
  color: var(--color-muted);
  text-decoration: none;
  transition: color var(--transition);
}
.back-link:hover {
  color: var(--color-accent);
}
.back-link-icon {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
}

/* -------- セクション（フェードイン + スライドアップ） -------- */
.section {
  padding: var(--space-lg) 0;
  opacity: 0;
  animation: fade-up 0.8s ease forwards;
}
.section + .section {
  border-top: 1px solid var(--color-border);
}

@keyframes fade-up {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.section-title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.15rem;
  margin-bottom: var(--space-md);
  letter-spacing: 0.15em;
}

/* -------- ヒーロー -------- */
.hero {
  padding: var(--space-md) 0 var(--space-sm);
}

.hero-kicker {
  font-size: 0.7rem;
  color: var(--color-muted);
  letter-spacing: 0.25em;
  margin-bottom: 10px;
  text-transform: uppercase;
}

.hero-title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.6rem;
  line-height: 1.6;
  letter-spacing: 0.1em;
  margin-bottom: 12px;
}

.hero-sub {
  font-size: 0.85rem;
  color: var(--color-muted);
  line-height: 1.85;
}

/* -------- カード -------- */
.card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
}

.card {
  display: block;
  padding: 18px 20px;
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  text-decoration: none;
  color: var(--color-text);
  transition:
    border-color var(--transition),
    background var(--transition);
  border-radius: 2px;
}
.card:hover {
  border-color: var(--color-accent);
  background: var(--color-bg);
}

.card-label {
  font-family: var(--font-utility);
  font-size: 0.68rem;
  color: var(--color-muted);
  letter-spacing: 0.2em;
  margin-bottom: 4px;
}

.card-title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1rem;
  letter-spacing: 0.08em;
  margin-bottom: 2px;
}

.card-meta {
  font-size: 0.75rem;
  color: var(--color-muted);
  letter-spacing: 0.08em;
}

/* -------- カード内 進捗バー -------- */
.card-progress {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 10px;
}

.card-progress-label {
  font-family: var(--font-utility);
  font-size: 0.72rem;
  color: var(--color-muted);
  letter-spacing: 0.1em;
  white-space: nowrap;
  min-width: 60px;
  text-align: right;
}

.card-progress-bar {
  flex: 1;
  height: 2px;
  background: var(--color-border);
  position: relative;
  overflow: hidden;
}

.card-progress-bar-fill {
  position: absolute;
  inset: 0 auto 0 0;
  background: var(--color-accent);
  width: 0%;
  transition: width 0.5s ease;
}

/* -------- カテゴリ アコーディオン -------- */
.axis-accordion {
  padding: 0;
}
.axis-accordion[open] {
  padding-bottom: var(--space-md);
}
.axis-accordion > summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: var(--space-md) 0;
  transition: color var(--transition);
}
.axis-accordion > summary::-webkit-details-marker {
  display: none;
}
.axis-accordion > summary:hover .axis-accordion-title {
  color: var(--color-accent);
}

.axis-accordion-title-wrap {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 0;
}
.axis-accordion-title {
  margin: 0;
  transition: color var(--transition);
}
.axis-accordion-meta {
  font-family: var(--font-utility);
  font-size: 0.72rem;
  color: var(--color-muted);
  letter-spacing: 0.1em;
}

.axis-accordion-arrow {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  font-size: 1.1rem;
  color: var(--color-muted);
  border: 1px solid var(--color-border);
  border-radius: 2px;
  transition:
    transform var(--transition),
    color var(--transition),
    border-color var(--transition);
  line-height: 1;
}
.axis-accordion[open] > summary .axis-accordion-arrow {
  transform: rotate(45deg);
  color: var(--color-accent);
  border-color: var(--color-accent);
}

.axis-accordion-body {
  animation: accordion-reveal 0.3s ease;
}

@keyframes accordion-reveal {
  from {
    opacity: 0;
    transform: translateY(-4px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* -------- ルビ（フリガナ） -------- */
ruby rt {
  font-family: var(--font-utility);
  font-size: 0.625rem; /* DESIGN.md のルビサイズ */
  color: var(--color-muted); /* rgba(51,51,51,0.7) と等価 */
  font-weight: 500;
}

/* -------- フラッシュカード学習画面 -------- */
.flashcard-stage {
  flex: 1;
  padding: var(--space-md) 0 var(--space-lg);
  display: flex;
  flex-direction: column;
}

.progress {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: var(--space-md);
  font-size: 0.72rem;
  color: var(--color-muted);
  letter-spacing: 0.15em;
}

.progress-bar {
  flex: 1;
  height: 1px;
  background: var(--color-border);
  position: relative;
}

.progress-bar-fill {
  position: absolute;
  inset: 0 auto 0 0;
  background: var(--color-accent);
  width: 40%;
}

.flashcard {
  position: relative;
  aspect-ratio: 1 / 1;
  cursor: pointer;
  user-select: none;
  touch-action: pan-y;
  perspective: 1200px;
  transition:
    box-shadow var(--transition),
    transform var(--transition),
    opacity var(--transition);
  will-change: transform;
}
.flashcard.has-been-flipped {
  cursor: grab;
}
.flashcard.has-been-flipped:active {
  cursor: grabbing;
}
.flashcard.is-dragging {
  transition: box-shadow 0.15s ease;
  box-shadow: 0 18px 40px rgb(51 51 51 / 18%);
}
.flashcard.is-exit-right {
  transform: translateX(130%) rotate(12deg) !important;
  opacity: 0;
}
.flashcard.is-exit-left {
  transform: translateX(-130%) rotate(-12deg) !important;
  opacity: 0;
}

/* 3D フリップ用の内側コンテナ。表/裏面はこの中に絶対配置される。 */
.flashcard-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 260ms cubic-bezier(0.5, 0, 0.5, 1);
  transform-style: preserve-3d;
}
.flashcard.is-flipped .flashcard-inner {
  transform: rotateY(180deg);
}

.flashcard-face {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  padding: var(--space-md);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  backface-visibility: hidden;
  transition: border-color var(--transition);
}
.flashcard:hover .flashcard-face {
  border-color: var(--color-accent);
}
.flashcard-face-back {
  background: var(--color-bg-alt);
  transform: rotateY(180deg);
}

.flashcard-jp {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 2.6rem;
  letter-spacing: 0.1em;
  line-height: 1.5;
}

.flashcard-reading {
  font-family: var(--font-utility);
  font-size: 0.8rem;
  color: var(--color-muted);
  margin-top: 14px;
  letter-spacing: 0.25em;
}

.flashcard-translation {
  font-family: var(--font-utility);
  font-size: 1.25rem;
  color: var(--color-text);
  line-height: 1.6;
}

.flashcard-pos {
  font-size: 0.72rem;
  color: var(--color-muted);
  margin-top: 18px;
  letter-spacing: 0.2em;
}

.flashcard-example {
  margin-top: 20px;
  padding-top: 14px;
  border-top: 1px solid var(--color-border);
}

.flashcard-example-translation {
  font-family: var(--font-utility);
  font-size: 0.82rem;
  color: var(--color-muted);
  line-height: 1.7;
  margin-top: 6px;
  letter-spacing: 0.05em;
}

.audio-btn {
  position: absolute;
  top: 12px;
  right: 12px;
  width: 36px;
  height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 2px;
  color: var(--color-muted);
  cursor: pointer;
  transition:
    color var(--transition),
    border-color var(--transition),
    background var(--transition);
  z-index: 2;
}

.audio-btn:hover {
  color: var(--color-accent);
  border-color: var(--color-accent);
}

.audio-btn.is-playing {
  color: var(--color-accent);
  border-color: var(--color-accent);
  background: var(--color-bg-alt);
}

.flashcard-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: var(--space-md);
}

/* -------- スワイプ UI -------- */
.flashcard-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.6rem;
  letter-spacing: 0.3em;
  pointer-events: none;
  opacity: 0;
  z-index: 1;
  text-transform: uppercase;
}
.flashcard-overlay-right {
  background: color-mix(in srgb, var(--color-accent) 18%, transparent);
  color: var(--color-accent);
  opacity: var(--swipe-right-opacity, 0);
}
.flashcard-overlay-left {
  background: color-mix(in srgb, var(--color-highlight) 45%, transparent);
  color: #8a4a4a;
  opacity: var(--swipe-left-opacity, 0);
}

/* カード外のヒント領域。初回は「タップしてめくる」のみ、フリップ後は
   「左右にスワイプ」+ 左右ラベル。 */
.flashcard-hint-area {
  margin-top: var(--space-md);
  padding: 0 8px;
  min-height: 56px;
}

.flashcard-hint-primary {
  text-align: center;
  font-size: 0.72rem;
  color: var(--color-muted);
  letter-spacing: 0.3em;
  transition: color var(--transition);
}
.flashcard-hint-area.is-swipe-ready .flashcard-hint-primary {
  color: var(--color-text);
}

.flashcard-swipe-hints {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 10px;
  font-size: 0.72rem;
  letter-spacing: 0.25em;
}
.flashcard-swipe-hints[hidden] {
  display: none;
}
.flashcard-swipe-hint-right {
  color: var(--color-accent);
}
.flashcard-swipe-hint-left {
  color: #8a4a4a;
}

/* -------- リスト選択モーダル -------- */
.mode-choices {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  margin-top: 8px;
}

.mode-choice {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 4px;
  padding: 16px 18px;
  text-align: left;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 2px;
  color: var(--color-text);
  cursor: pointer;
  transition:
    background var(--transition),
    border-color var(--transition),
    color var(--transition);
}
.mode-choice:hover {
  border-color: var(--color-accent);
  background: var(--color-bg-alt);
}
.mode-choice-primary {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-bg);
}
.mode-choice-primary:hover {
  background: var(--color-bg);
  color: var(--color-accent);
}
.mode-choice-label {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1rem;
  letter-spacing: 0.15em;
}
.mode-choice-hint {
  font-family: var(--font-utility);
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  opacity: 0.85;
}

/* -------- 学習チュートリアル -------- */
.tutorial-panel {
  max-width: 380px;
}

.tutorial-demo {
  position: relative;
  height: 120px;
  margin: 8px 0 var(--space-md);
  border: 1px solid var(--color-border);
  background: var(--color-bg-alt);
  border-radius: 2px;
  overflow: hidden;
}

.tutorial-demo-card {
  position: absolute;
  inset: 20px;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  border-radius: 2px;
  animation: tutorial-swipe 3.2s ease-in-out infinite;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
.tutorial-demo-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1rem;
  letter-spacing: 0.25em;
  opacity: 0;
}
.tutorial-demo-overlay-right {
  background: color-mix(in srgb, var(--color-accent) 18%, transparent);
  color: var(--color-accent);
  animation: tutorial-overlay-right 3.2s ease-in-out infinite;
}
.tutorial-demo-overlay-left {
  background: color-mix(in srgb, var(--color-highlight) 45%, transparent);
  color: #8a4a4a;
  animation: tutorial-overlay-left 3.2s ease-in-out infinite;
}

@keyframes tutorial-swipe {
  0%,
  10% {
    transform: translateX(0) rotate(0);
  }
  30% {
    transform: translateX(-50%) rotate(-10deg);
  }
  40%,
  55% {
    transform: translateX(0) rotate(0);
  }
  75% {
    transform: translateX(50%) rotate(10deg);
  }
  85%,
  100% {
    transform: translateX(0) rotate(0);
  }
}

@keyframes tutorial-overlay-left {
  0%,
  15% {
    opacity: 0;
  }
  30% {
    opacity: 1;
  }
  45%,
  100% {
    opacity: 0;
  }
}

@keyframes tutorial-overlay-right {
  0%,
  60% {
    opacity: 0;
  }
  75% {
    opacity: 1;
  }
  90%,
  100% {
    opacity: 0;
  }
}

.tutorial-list {
  list-style: none;
  padding: 0;
  margin: 0 0 var(--space-md);
  font-size: 0.88rem;
  line-height: 1.9;
  color: var(--color-text);
}
.tutorial-list li {
  padding: 6px 0;
  border-bottom: 1px solid var(--color-border);
}
.tutorial-list li:last-child {
  border-bottom: none;
}

.tutorial-dismiss {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 0 var(--space-md);
  font-size: 0.82rem;
  color: var(--color-muted);
  cursor: pointer;
}
.tutorial-dismiss input[type='checkbox'] {
  accent-color: var(--color-accent);
  width: 16px;
  height: 16px;
  cursor: pointer;
}

.tutorial-start {
  width: 100%;
}

/* -------- 結果画面 -------- */
.result-stage {
  flex: 1;
  padding: var(--space-lg) 0;
  text-align: center;
  animation: fade-up 0.8s ease forwards;
}

.result-num {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 4.5rem;
  color: var(--color-accent);
  letter-spacing: 0.05em;
  line-height: 1;
}

.result-num .unit {
  font-size: 1.3rem;
  color: var(--color-muted);
  margin-left: 4px;
}

.result-label {
  font-size: 0.7rem;
  color: var(--color-muted);
  letter-spacing: 0.3em;
  margin-top: 10px;
}

/* -------- 結果画面の累積進捗 -------- */
.result-progress {
  margin: var(--space-md) 0 var(--space-lg);
  padding: var(--space-md) 0;
  text-align: center;
}

.result-progress-label {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 3rem;
  color: var(--color-accent);
  letter-spacing: 0.05em;
  line-height: 1.1;
}

.result-progress-sep {
  color: var(--color-muted);
  margin: 0 6px;
  font-weight: 400;
}

.result-progress-bar {
  position: relative;
  height: 3px;
  background: var(--color-border);
  margin: 18px auto 12px;
  max-width: 280px;
  overflow: hidden;
}

.result-progress-bar-fill {
  position: absolute;
  inset: 0 auto 0 0;
  width: 0%;
  background: var(--color-accent);
  transition: width 0.8s ease;
}

.result-progress-caption {
  font-size: 0.7rem;
  color: var(--color-muted);
  letter-spacing: 0.3em;
  text-transform: uppercase;
}

.result-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin: var(--space-md) 0;
  padding: var(--space-md) 0;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.result-stat .num {
  font-family: var(--font-display);
  font-size: 1.4rem;
  color: var(--color-text);
}

.result-stat .label {
  font-size: 0.68rem;
  color: var(--color-muted);
  letter-spacing: 0.2em;
  margin-top: 2px;
}

/* -------- 設定画面 -------- */
.settings-list {
  list-style: none;
}

.settings-item {
  padding: var(--space-sm) 0;
  border-bottom: 1px solid var(--color-border);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
}
.settings-item:last-child {
  border-bottom: none;
}

.settings-label {
  font-size: 0.72rem;
  color: var(--color-muted);
  letter-spacing: 0.15em;
}

.settings-value-inline {
  font-family: var(--font-utility);
  font-size: 0.85rem;
}

.user-key-box {
  font-family: var(--font-utility);
  font-size: 0.95rem;
  word-break: break-all;
  padding: 16px;
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 2px;
  margin: 8px 0 12px;
  letter-spacing: 0.1em;
  text-align: center;
}

.settings-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

/* -------- 言語リスト -------- */
.lang-list {
  list-style: none;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.lang-item {
  padding: 12px 10px;
  text-align: center;
  border: 1px solid var(--color-border);
  border-radius: 2px;
  font-size: 0.85rem;
  letter-spacing: 0.05em;
  cursor: pointer;
  background: var(--color-bg);
  transition: all var(--transition);
}
.lang-item:hover {
  background: var(--color-highlight);
  border-color: var(--color-highlight);
}

.lang-item.active {
  background: var(--color-accent);
  color: var(--color-bg);
  border-color: var(--color-accent);
}

/* -------- 縦書きアクセント -------- */
.vertical-title {
  writing-mode: vertical-rl;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1rem;
  letter-spacing: 0.4em;
  padding: 4px 8px 4px 0;
  color: var(--color-muted);
}

/* -------- フッター -------- */
.app-footer {
  margin-top: auto;
  padding: var(--space-md) 0 var(--space-sm);
  border-top: 1px solid var(--color-border);
  font-size: 0.65rem;
  color: var(--color-muted);
  text-align: center;
  letter-spacing: 0.3em;
}

/* -------- モーダル（ユーザーキー引き継ぎなど） -------- */
.modal {
  position: fixed;
  inset: 0;
  z-index: 90;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
}

.modal[hidden] {
  display: none;
}

.modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgb(51 51 51 / 45%);
  animation: modal-fade 0.25s ease forwards;
}

.modal-panel {
  position: relative;
  width: 100%;
  max-width: 420px;
  padding: var(--space-md);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 2px;
  animation: modal-rise 0.3s ease forwards;
}

@keyframes modal-fade {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes modal-rise {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.modal-close {
  position: absolute;
  top: 6px;
  right: 8px;
  width: 32px;
  height: 32px;
  background: none;
  border: none;
  color: var(--color-muted);
  font-size: 1.5rem;
  line-height: 1;
  cursor: pointer;
  transition: color var(--transition);
}

.modal-close:hover {
  color: var(--color-text);
}

.modal-title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.1rem;
  letter-spacing: 0.15em;
  margin-bottom: 12px;
}

.modal-desc {
  font-size: 0.85rem;
  color: var(--color-muted);
  margin-bottom: var(--space-md);
  line-height: 1.7;
}

.modal-form {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.modal-label {
  font-size: 0.72rem;
  color: var(--color-muted);
  letter-spacing: 0.15em;
}

.modal-input {
  width: 100%;
  padding: 12px 14px;
  font-family: var(--font-utility);
  font-size: 0.95rem;
  color: var(--color-text);
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 2px;
  outline: none;
  transition: border-color var(--transition);
  letter-spacing: 0.05em;
}

.modal-input:focus {
  border-color: var(--color-accent);
}

.modal-input[aria-invalid='true'] {
  border-color: #9a3b3b;
}

.modal-error {
  font-size: 0.78rem;
  color: #9a3b3b;
  line-height: 1.6;
}

.modal-error[hidden] {
  display: none;
}

.modal-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: 10px;
}

body.is-modal-open {
  overflow: hidden;
}

/* -------- トースト（コピー通知など） -------- */
.toast {
  position: fixed;
  left: 50%;
  bottom: 40px;
  transform: translateX(-50%) translateY(20px);
  padding: 10px 20px;
  background: var(--color-text);
  color: var(--color-bg);
  font-size: 0.78rem;
  letter-spacing: 0.15em;
  border-radius: 2px;
  opacity: 0;
  pointer-events: none;
  transition:
    opacity var(--transition),
    transform var(--transition);
  z-index: 100;
}

.toast.is-visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}