:root {
  --bg: #f6f4ef;
  --card: #ffffff;
  --text: #1f2328;
  --muted: #6b6f76;
  --border: #e2ded5;
  --accent: #b5452f;
  --accent-soft: #f6e4df;
  --good: #2f7d4a;
  --good-soft: #e3f2e7;
  --bad: #b3261e;
  --bad-soft: #fbe5e3;
  --note: #8a5a00;
  --note-soft: #fff4dc;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #17181b;
    --card: #212327;
    --text: #e8e6e1;
    --muted: #9a9ea5;
    --border: #34373d;
    --accent: #e0775f;
    --accent-soft: #3a2621;
    --good: #6cc98a;
    --good-soft: #1d3324;
    --bad: #f08a80;
    --bad-soft: #3d2120;
    --note: #f0c56a;
    --note-soft: #3a3020;
  }
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", "Segoe UI", sans-serif;
  line-height: 1.6;
}
button { font: inherit; color: inherit; }

.topbar {
  display: flex; align-items: center; justify-content: space-between;
  max-width: 760px; margin: 0 auto; padding: 18px 16px;
}
.brand { font-size: 1.4rem; font-weight: 700; color: var(--accent); text-decoration: none; }
.brand span + span { font-size: 0.95rem; font-weight: 500; color: var(--muted); margin-left: 6px; }
.toggle { color: var(--muted); font-size: 0.9rem; cursor: pointer; user-select: none; }

main { max-width: 760px; margin: 0 auto; padding: 0 16px 60px; }

body.no-furigana rt { visibility: hidden; }
rt { font-size: 0.55em; color: var(--muted); }

h1 { font-size: 1.5rem; margin: 8px 0 4px; }
.sub { color: var(--muted); margin: 0 0 20px; }

.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 12px; }
.quiz-card {
  background: var(--card); border: 1px solid var(--border); border-radius: 12px;
  padding: 16px; cursor: pointer; text-align: left; display: flex; flex-direction: column; gap: 6px;
  transition: border-color .15s, transform .15s;
}
.quiz-card:hover { border-color: var(--accent); transform: translateY(-1px); }
.quiz-card h3 { margin: 0; font-size: 1.05rem; }
.quiz-card p { margin: 0; color: var(--muted); font-size: 0.9rem; flex: 1; }
.meta { display: flex; gap: 8px; align-items: center; font-size: 0.8rem; color: var(--muted); }
.pill { background: var(--accent-soft); color: var(--accent); border-radius: 99px; padding: 1px 8px; font-weight: 600; }
.best { margin-left: auto; }
.mix-card { border-style: dashed; }

.progress { height: 6px; background: var(--border); border-radius: 99px; overflow: hidden; margin: 6px 0 4px; }
.progress div { height: 100%; background: var(--accent); transition: width .25s; }
.progress-label { display: flex; justify-content: space-between; color: var(--muted); font-size: 0.85rem; }

.question {
  background: var(--card); border: 1px solid var(--border); border-radius: 14px;
  padding: 24px 20px; margin-top: 16px;
}
.prompt { font-size: 1.45rem; line-height: 2.2; margin: 0 0 20px; word-break: keep-all; overflow-wrap: anywhere; }
.options { display: grid; gap: 10px; }
.option {
  display: flex; align-items: center; gap: 12px; width: 100%;
  background: transparent; border: 1.5px solid var(--border); border-radius: 10px;
  padding: 10px 14px; font-size: 1.15rem; cursor: pointer; text-align: left; line-height: 2;
}
.option:hover:not(:disabled) { border-color: var(--accent); }
.option:disabled { cursor: default; }
.option .key {
  flex: none; width: 26px; height: 26px; border-radius: 6px; background: var(--border);
  display: grid; place-items: center; font-size: 0.8rem; font-weight: 700; line-height: 1;
}
.option.dunno { font-size: 0.95rem; color: var(--muted); border-style: dashed; }
.option.correct { border-color: var(--good); background: var(--good-soft); }
.option.correct .key { background: var(--good); color: #fff; }
.option.wrong { border-color: var(--bad); background: var(--bad-soft); }
.option.wrong .key { background: var(--bad); color: #fff; }
.option.faded { opacity: 0.5; }

.feedback { margin-top: 18px; border-radius: 10px; padding: 14px 16px; border: 1px solid var(--border); }
.feedback.good { background: var(--good-soft); border-color: transparent; }
.feedback.bad { background: var(--bad-soft); border-color: transparent; }
.feedback h4 { margin: 0 0 6px; font-size: 1.05rem; }
.feedback.good h4 { color: var(--good); }
.feedback.bad h4 { color: var(--bad); }
.feedback p { margin: 6px 0; }
.why-wrong { background: var(--note-soft); border-left: 3px solid var(--note); padding: 8px 12px; border-radius: 6px; margin: 8px 0; }
.why-wrong strong { color: var(--note); }
.translation { color: var(--muted); font-style: italic; }
.label { font-weight: 700; font-size: 0.8rem; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); display: block; margin-top: 10px; }

.actions { display: flex; gap: 10px; justify-content: flex-end; margin-top: 16px; flex-wrap: wrap; }
.btn {
  background: var(--accent); color: #fff; border: 0; border-radius: 10px; padding: 10px 20px;
  font-weight: 600; cursor: pointer;
}
.btn.secondary { background: transparent; color: var(--text); border: 1.5px solid var(--border); }
.hint { color: var(--muted); font-size: 0.8rem; text-align: center; margin-top: 14px; }

.score-big { font-size: 3rem; font-weight: 800; color: var(--accent); margin: 10px 0 0; }
.review-item { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 16px; margin-top: 12px; }
.review-item .prompt { font-size: 1.15rem; margin-bottom: 8px; }
.review-item .ans { margin: 2px 0; }
.review-item .ans.yours { color: var(--bad); }
.review-item .ans.right { color: var(--good); }

@media (max-width: 520px) {
  .prompt { font-size: 1.25rem; }
  .question { padding: 18px 14px; }
}

/* ---------- sections, view switch, list view ---------- */
a { color: var(--accent); }
a.quiz-card { color: inherit; text-decoration: none; }
a.btn { display: inline-block; text-decoration: none; }
.btn.small { padding: 5px 12px; font-size: 0.85rem; }
.muted { color: var(--muted); font-size: 0.85rem; }
.crumb { margin: 0 0 4px; font-size: 0.9rem; }
.crumb a { text-decoration: none; }

.home-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 16px; flex-wrap: wrap; }
.section-title { font-size: 1.1rem; margin: 28px 0 12px; padding-bottom: 6px; border-bottom: 1px solid var(--border); }
section:first-of-type .section-title { margin-top: 8px; }

.segmented { display: inline-flex; border: 1.5px solid var(--border); border-radius: 10px; overflow: hidden; margin-top: 12px; }
.segmented button { background: transparent; border: 0; padding: 6px 14px; cursor: pointer; font-size: 0.9rem; color: var(--muted); }
.segmented button.active { background: var(--accent); color: #fff; }

.list { background: var(--card); border: 1px solid var(--border); border-radius: 12px; overflow: hidden; }
.list-row { display: flex; align-items: center; gap: 12px; padding: 12px 14px; border-top: 1px solid var(--border); }
.list-row:first-child { border-top: 0; }
.list-num { flex: none; width: 24px; text-align: center; color: var(--muted); font-weight: 700; font-size: 0.9rem; }
.list-main { flex: 1; min-width: 0; }
.list-title { font-weight: 600; color: var(--text); text-decoration: none; }
.list-title:hover { color: var(--accent); }
.list-points { margin-top: 2px; font-size: 0.85rem; color: var(--muted); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.list-points rt, .quiz-card p rt { display: none; }
.chip { font-size: 0.75rem; background: var(--bg); border: 1px solid var(--border); border-radius: 99px; padding: 0 8px; line-height: 1.8; }
.chip rt { display: none; }
.list-side { flex: none; display: flex; align-items: center; gap: 10px; }
.list-side .best { margin: 0; font-size: 0.8rem; color: var(--good); }

/* ---------- grammar guides ---------- */
details.guide { background: var(--card); border: 1px solid var(--border); border-radius: 12px; margin-top: 12px; }
details.guide summary { cursor: pointer; padding: 12px 16px; list-style: none; display: flex; flex-direction: column; gap: 2px; }
details.guide summary::-webkit-details-marker { display: none; }
details.guide summary::after { content: "Show explanation ▾"; font-size: 0.78rem; color: var(--accent); font-weight: 600; margin-top: 4px; }
details.guide[open] summary::after { content: "Hide ▴"; }
.guide-title { font-weight: 700; }
.guide-summary { color: var(--muted); font-size: 0.92rem; }
.guide-body { padding: 0 16px 14px; border-top: 1px solid var(--border); }
.guide-body p { margin: 10px 0; }
.guide-body ul { margin: 6px 0; padding-left: 22px; }
.guide-body li { margin: 3px 0; }
ul.examples { list-style: none; padding: 0; }
ul.examples li { display: flex; flex-direction: column; padding: 8px 12px; background: var(--bg); border-radius: 8px; margin: 6px 0; }
.ex-jp { font-size: 1.1rem; line-height: 2; }
.ex-en { color: var(--muted); font-size: 0.9rem; }
.feedback + details.guide { margin-top: 10px; }

@media (max-width: 520px) {
  .list-row { flex-wrap: wrap; }
  .list-side { width: 100%; justify-content: flex-end; }
}

/* ---------- resume banner ---------- */
.resume-banner {
  display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap;
  background: var(--accent-soft); border: 1px solid var(--accent); border-radius: 12px;
  padding: 12px 16px; margin: 4px 0 8px;
}
.resume-banner > div:first-child { display: flex; flex-direction: column; }
.resume-actions { display: flex; gap: 8px; }

/* Mandarin: Chinese glyphs and slightly larger pinyin */
html:lang(zh-CN) body { font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Noto Sans SC", "Microsoft YaHei", sans-serif; }
html:lang(zh-CN) rt { font-size: 0.6em; }
.home-controls { display: flex; gap: 8px; flex-wrap: wrap; }
html:lang(zh-TW) body { font-family: -apple-system, BlinkMacSystemFont, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", sans-serif; }
html:lang(zh-TW) rt { font-size: 0.6em; }
.topbar-right { display: flex; align-items: center; gap: 12px; }
.segmented.mini button { padding: 4px 10px; font-size: 0.95rem; }
[hidden] { display: none !important; }
/* Pinyin is wider than its characters: keep neighbouring readings apart. */
html:lang(zh-CN) ruby, html:lang(zh-TW) ruby { margin: 0 0.18em; }
html:lang(zh-CN) .prompt, html:lang(zh-TW) .prompt { line-height: 2.3; }
.sound-toggle { background: none; border: 0; padding: 2px 4px; font-size: 1.05rem; cursor: pointer; line-height: 1; opacity: 0.8; }
.sound-toggle:hover { opacity: 1; }

/* After answering, options can be tapped to read their explanation */
.options.answered .option:not(.dunno) { cursor: pointer; }
.option.inspected { outline: 2px solid var(--accent); outline-offset: 2px; opacity: 1; }
.inspect-hint { color: var(--muted); font-size: 0.85rem; margin: 6px 0 10px; }
.options.answered .option.faded { opacity: 0.7; }
.options.answered .option.faded:hover, .options.answered .option.faded.inspected { opacity: 1; }

/* ---------- home: levels, groups, status ---------- */
body.home main, body.home .topbar { max-width: 1120px; }
.home-layout { display: block; }
.levels {
  display: flex; gap: 8px; overflow-x: auto; scrollbar-width: none;
  position: sticky; top: 0; z-index: 5; background: var(--bg);
  margin: 12px -16px 0; padding: 10px 16px;
}
.levels::-webkit-scrollbar { display: none; }
.level {
  flex: none; display: grid; grid-template-columns: auto auto; column-gap: 8px; align-items: baseline;
  background: var(--card); border: 1.5px solid var(--border); border-radius: 12px;
  padding: 6px 12px 8px; cursor: pointer; text-align: left; min-width: 74px;
}
.level.active { border-color: var(--accent); background: var(--accent-soft); }
.level .lv { font-weight: 700; font-size: 1rem; }
.level .lv-count { font-size: 0.75rem; color: var(--muted); }
.level .bar { grid-column: 1 / -1; margin-top: 4px; }
.bar { display: block; height: 4px; background: var(--border); border-radius: 99px; overflow: hidden; }
.bar > span { display: block; height: 100%; background: var(--good); }
.level-head .bar { max-width: 280px; margin-top: 6px; }

.search input {
  width: 100%; font: inherit; color: var(--text); background: var(--card);
  border: 1.5px solid var(--border); border-radius: 12px; padding: 10px 14px; margin: 12px 0 4px;
}
.search input:focus { outline: none; border-color: var(--accent); }

.level-head { display: flex; justify-content: space-between; align-items: flex-end; gap: 12px; flex-wrap: wrap; margin: 14px 0 12px; }
.level-head h2 { margin: 0; font-size: 1.25rem; }
.level-head .muted { font-size: 0.85rem; }
.filters { margin-top: 0; }

.mix-banner {
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
  background: var(--card); border: 1.5px dashed var(--border); border-radius: 12px;
  padding: 10px 14px; color: var(--text); text-decoration: none; margin-bottom: 8px;
}
.mix-banner:hover { border-color: var(--accent); }

details.qgroup { margin-top: 14px; }
details.qgroup > summary {
  display: flex; justify-content: space-between; align-items: center; cursor: pointer; list-style: none;
  font-weight: 700; padding: 6px 2px; border-bottom: 1px solid var(--border); margin-bottom: 10px;
}
details.qgroup > summary::-webkit-details-marker { display: none; }
details.qgroup > summary::after { content: "▾"; color: var(--muted); margin-left: 8px; }
details.qgroup:not([open]) > summary::after { content: "▸"; }
details.qgroup > summary > span:first-child { flex: 1; }

.qc-head { display: flex; align-items: center; gap: 8px; }
.quiz-card .pill, .list-title .pill { margin-right: 6px; font-size: 0.75rem; vertical-align: middle; }
.quiz-card p { display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }

.dot { flex: none; width: 10px; height: 10px; border-radius: 50%; border: 2px solid var(--muted); opacity: .6; }
.dot.progress { border-color: var(--accent); background: var(--accent); opacity: 1; }
.dot.weak { border-color: var(--note); background: var(--note); opacity: 1; }
.dot.done { border-color: var(--good); background: var(--good); opacity: 1; }
.best { margin-left: auto; font-weight: 600; color: var(--muted); }
.list-side .best { color: var(--muted); }
.empty { margin: 20px 0; }

@media (min-width: 900px) {
  .home-layout { display: grid; grid-template-columns: 190px 1fr; gap: 28px; align-items: start; }
  .levels {
    flex-direction: column; overflow: visible; margin: 0; padding: 0;
    position: sticky; top: 16px; background: none;
  }
  .level { min-width: 0; padding: 8px 12px 10px; }
  .search input { margin-top: 0; }
  .grid { grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); }
}
@media (max-width: 600px) {
  body.home .sub { display: none; }
  body.home h1 { font-size: 1.3rem; }
}

/* ---------- typed answers ---------- */
.typed { display: grid; gap: 8px; margin-top: 8px; }
.typed input {
  font: inherit; font-size: 1.25rem; color: var(--text); background: var(--card);
  border: 2px solid var(--border); border-radius: 12px; padding: 12px 14px; width: 100%;
}
.typed input:focus { outline: none; border-color: var(--accent); }
.typed input.correct { border-color: var(--good); background: var(--good-soft); }
.typed input.wrong { border-color: var(--bad); background: var(--bad-soft); }
.kana-preview { min-height: 1.2em; font-size: 1rem; }
.typed-actions { display: flex; gap: 8px; flex-wrap: wrap; }
.hint-box { background: var(--note-soft); color: var(--note); border-radius: 10px; padding: 8px 12px; font-size: 0.95rem; }

.review-banner {
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
  background: var(--good-soft); border: 1.5px solid var(--good); border-radius: 12px;
  padding: 10px 14px; color: var(--text); text-decoration: none; margin-bottom: 12px;
}

/* Account & sync */
.topbar { position: relative; }
.account-btn {
  display: inline-flex; align-items: center; gap: 6px; background: none; color: var(--muted);
  border: 1px solid var(--border); border-radius: 999px; padding: 4px 10px; font: inherit; font-size: 0.9rem; cursor: pointer;
}
.account-btn:hover { color: var(--text); }
.account-panel {
  position: absolute; top: 100%; right: 16px; z-index: 20; width: min(340px, calc(100vw - 32px));
  background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 16px;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.35);
}
.account-panel h3 { margin: 0 0 8px; }
.account-panel p { margin: 6px 0; }
.account-panel .or { margin-top: 14px; }
.account-panel .small { font-size: 0.85rem; }
.account-panel .actions { display: flex; gap: 8px; flex-wrap: wrap; }
.login-email { display: flex; gap: 8px; }
.login-email input {
  flex: 1; min-width: 0; padding: 8px 10px; border-radius: 8px; border: 1px solid var(--border);
  background: var(--bg); color: var(--text); font: inherit;
}
@media (max-width: 600px) { .account-btn .label { display: none; } }

/* Read-aloud buttons */
.listen {
  background: none; border: 1px solid var(--border); border-radius: 999px; cursor: pointer;
  padding: 1px 8px; margin-left: 8px; font-size: 0.85rem; line-height: 1.4; vertical-align: middle;
}
.listen:hover, .listen.playing { border-color: var(--accent); }