:root {
  --color-primary: #0f7a82;
  --color-primary-dark: #0a5960;
  --color-primary-soft: #e4f1f0;
  --color-accent: #c9564f;
  --color-accent-bg: #fbe9e7;
  --color-success: #2c8a49;
  --color-success-bg: #e3f4e7;
  --color-bg: #f4f6f5;
  --color-card: #ffffff;
  --color-card-hover: #eef2f1;
  --color-text: #1c2b2e;
  --color-text-sub: #5c6e70;
  --color-border: #dde4e2;

  --color-unlearned: #9aa8a6;
  --color-learned: #3f7fb0;
  --color-perfect: #d79b2c;

  --radius: 14px;
  --shadow: 0 2px 10px rgba(15, 30, 32, 0.08);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --color-primary: #3fb8bd;
    --color-primary-dark: #7fd6da;
    --color-primary-soft: #16333338;
    --color-accent: #e2837c;
    --color-accent-bg: #3a2321;
    --color-success: #6fc98a;
    --color-success-bg: #1d3324;
    --color-bg: #101a1b;
    --color-card: #172426;
    --color-card-hover: #1e2e30;
    --color-text: #e7eeee;
    --color-text-sub: #9fb2b2;
    --color-border: #2a3a3c;

    --color-unlearned: #7c8c8a;
    --color-learned: #6fa8d6;
    --color-perfect: #e7b34f;

    --shadow: 0 2px 12px rgba(0, 0, 0, 0.35);
  }
}

:root[data-theme="dark"] {
  --color-primary: #3fb8bd;
  --color-primary-dark: #7fd6da;
  --color-primary-soft: #16333338;
  --color-accent: #e2837c;
  --color-accent-bg: #3a2321;
  --color-success: #6fc98a;
  --color-success-bg: #1d3324;
  --color-bg: #101a1b;
  --color-card: #172426;
  --color-card-hover: #1e2e30;
  --color-text: #e7eeee;
  --color-text-sub: #9fb2b2;
  --color-border: #2a3a3c;

  --color-unlearned: #7c8c8a;
  --color-learned: #6fa8d6;
  --color-perfect: #e7b34f;

  --shadow: 0 2px 12px rgba(0, 0, 0, 0.35);
}

* {
  box-sizing: border-box;
}

html {
  color-scheme: light dark;
}

body {
  margin: 0;
  font-family: "Hiragino Kaku Gothic ProN", "Hiragino Sans", "Yu Gothic", "Noto Sans JP", "Malgun Gothic", sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
  transition: background 0.15s ease, color 0.15s ease;
}

.app-header {
  background: var(--color-primary);
  color: #fff;
  position: sticky;
  top: 0;
  z-index: 10;
  box-shadow: var(--shadow);
}

.header-inner {
  max-width: 840px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  padding: 12px 16px;
}

.header-title {
  background: none;
  border: none;
  color: #fff;
  font-size: 1.1rem;
  font-weight: 700;
  cursor: pointer;
  padding: 4px 0;
}

#app {
  max-width: 840px;
  margin: 0 auto;
  padding: 20px 16px 60px;
}

.screen.hidden {
  display: none;
}

.screen-title {
  font-size: 1.15rem;
  margin: 0 0 6px;
}

.screen-desc {
  color: var(--color-text-sub);
  font-size: 0.88rem;
  margin: 0 0 20px;
  line-height: 1.6;
}

/* ---- Home ---- */
.mode-cards {
  display: grid;
  gap: 14px;
  grid-template-columns: 1fr;
}
@media (min-width: 560px) {
  .mode-cards {
    grid-template-columns: 1fr 1fr;
  }
}

.mode-card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 22px 18px;
  text-align: left;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}
.mode-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(20, 35, 40, 0.14);
}
.mode-main {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--color-primary-dark);
}
.mode-sub {
  font-size: 0.82rem;
  color: var(--color-text-sub);
}

/* ---- Sub header / back nav ---- */
.sub-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 6px;
  flex-wrap: wrap;
}

.back-btn {
  background: none;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  padding: 6px 12px;
  font-size: 0.8rem;
  color: var(--color-text-sub);
  cursor: pointer;
}
.back-btn:hover {
  background: var(--color-card-hover);
}

.legend {
  display: flex;
  gap: 16px;
  margin: 10px 0 16px;
  font-size: 0.78rem;
  color: var(--color-text-sub);
  flex-wrap: wrap;
}
.legend-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
}
.dot-unlearned { background: var(--color-unlearned); }
.dot-learned { background: var(--color-learned); }
.dot-perfect { background: var(--color-perfect); }

/* ---- Stage grid ---- */
.stage-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 12px;
}

.stage-card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 14px;
  text-align: left;
  cursor: pointer;
}
.stage-card:hover {
  border-color: var(--color-primary);
}

.stage-card-top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 4px;
}

.stage-num {
  font-weight: 700;
  color: var(--color-primary-dark);
  font-size: 0.9rem;
}

.stage-title {
  font-size: 0.78rem;
  color: var(--color-text-sub);
  margin-bottom: 10px;
  min-height: 2.2em;
  line-height: 1.4;
}

.stage-bar {
  display: flex;
  height: 8px;
  border-radius: 999px;
  overflow: hidden;
  background: var(--color-unlearned);
  margin-bottom: 8px;
}
.stage-bar-seg-learned { background: var(--color-learned); }
.stage-bar-seg-perfect { background: var(--color-perfect); }

.stage-counts {
  display: flex;
  gap: 8px;
  font-size: 0.72rem;
  color: var(--color-text-sub);
  flex-wrap: wrap;
}
.stage-counts b {
  color: var(--color-text);
}

/* ---- Category select ---- */
.category-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
}
.category-card {
  background: var(--color-card);
  border: 1px solid var(--color-border);
  border-left: 6px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 16px;
  text-align: left;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.category-card:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}
.category-card.cat-unlearned { border-left-color: var(--color-unlearned); }
.category-card.cat-learned { border-left-color: var(--color-learned); }
.category-card.cat-perfect { border-left-color: var(--color-perfect); }
.category-card.cat-all { border-left-color: var(--color-primary); }

.category-card-title {
  font-weight: 700;
  font-size: 0.98rem;
}
.category-card-count {
  font-size: 0.8rem;
  color: var(--color-text-sub);
}

/* ---- Quiz ---- */
.quiz-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}
.quiz-progress {
  font-size: 0.85rem;
  color: var(--color-text-sub);
  font-weight: 600;
}

.quiz-card {
  background: var(--color-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px 20px;
}

.quiz-question {
  text-align: center;
  margin-bottom: 26px;
}
.quiz-question .q-main {
  font-size: 1.7rem;
  font-weight: 700;
  color: var(--color-primary-dark);
  line-height: 1.4;
}
.quiz-question .q-sub {
  margin-top: 8px;
  font-size: 1rem;
  color: var(--color-text-sub);
}

.quiz-choices {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}
@media (min-width: 480px) {
  .quiz-choices {
    grid-template-columns: 1fr 1fr;
  }
}

.dontknow-btn {
  display: block;
  width: 100%;
  margin-top: 10px;
  background: none;
  border: 2px dashed var(--color-border);
  border-radius: 10px;
  padding: 12px;
  font-size: 0.9rem;
  color: var(--color-text-sub);
  cursor: pointer;
  transition: background 0.1s, border-color 0.1s;
}
.dontknow-btn:hover:not(:disabled) {
  border-color: var(--color-text-sub);
  background: var(--color-card-hover);
}
.dontknow-btn:disabled {
  cursor: default;
}
.dontknow-btn.incorrect {
  background: var(--color-accent-bg);
  border-style: solid;
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.choice-btn {
  background: var(--color-card);
  color: var(--color-text);
  border: 2px solid var(--color-border);
  border-radius: 10px;
  padding: 14px 12px;
  font-size: 1rem;
  cursor: pointer;
  text-align: center;
  line-height: 1.4;
  transition: background 0.1s, border-color 0.1s;
}
.choice-btn:hover:not(:disabled) {
  border-color: var(--color-primary);
}
.choice-btn .choice-kana {
  display: block;
  font-size: 0.78rem;
  color: var(--color-text-sub);
  margin-top: 3px;
}
.choice-btn:disabled {
  cursor: default;
}
.choice-btn.correct {
  background: var(--color-success-bg);
  border-color: var(--color-success);
}
.choice-btn.incorrect {
  background: var(--color-accent-bg);
  border-color: var(--color-accent);
}

.quiz-feedback {
  margin-top: 18px;
  text-align: center;
  font-size: 0.95rem;
  font-weight: 600;
}
.quiz-feedback.hidden {
  display: none;
}
.quiz-feedback.ok { color: var(--color-success); }
.quiz-feedback.ng { color: var(--color-accent); }

.next-btn, .primary-btn {
  display: block;
  margin: 20px auto 0;
  background: var(--color-primary);
  color: #fff;
  border: none;
  border-radius: 999px;
  padding: 12px 28px;
  font-size: 0.95rem;
  font-weight: 700;
  cursor: pointer;
}
.next-btn:hover, .primary-btn:hover {
  background: var(--color-primary-dark);
}
.next-btn.hidden {
  display: none;
}

/* ---- Result ---- */
.result-card {
  background: var(--color-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 26px 20px;
  text-align: center;
}
.result-score {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--color-primary-dark);
  margin-bottom: 18px;
}
.result-list {
  text-align: left;
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 20px;
  max-height: 320px;
  overflow-y: auto;
}
.result-row {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.85rem;
  padding: 8px 10px;
  border-radius: 8px;
  background: var(--color-card-hover);
}
.result-row.ng {
  background: var(--color-accent-bg);
}
.result-row .mark {
  font-weight: 700;
  width: 1.2em;
}
.result-row.ok .mark { color: var(--color-success); }
.result-row.ng .mark { color: var(--color-accent); }
.result-row .rk {
  font-weight: 700;
  min-width: 90px;
}
.result-row .rkana {
  color: var(--color-text-sub);
  font-size: 0.78rem;
}
.result-row .rj {
  margin-left: auto;
  color: var(--color-text-sub);
}

.result-actions {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.secondary-btn {
  background: none;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  padding: 10px 20px;
  font-size: 0.88rem;
  color: var(--color-text);
  cursor: pointer;
}
.secondary-btn:hover {
  background: var(--color-card-hover);
}