/* ===== 语文预习 · 视觉系统（与美术馆共用宣纸底色系） ===== */
:root {
  --paper: #f3eee1;
  --paper-deep: #eae3d0;
  --card: #fcfaf2;
  --ink: #2e2b24;
  --text: #3d392f;
  --text-dim: #8a8172;
  --gold: #9a7b1c;
  --gold-deep: #7c6213;
  --green: #4a7c4e;
  --line: #ddd3bc;
  --serif: "Songti SC", "STSong", "Noto Serif SC", "SimSun", serif;
  --kai: "Kaiti SC", "STKaiti", "KaiTi", serif;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
body { background: var(--paper); color: var(--text); font-family: var(--serif); font-size: 17px; min-height: 100vh; -webkit-font-smoothing: antialiased; }
button { font-family: inherit; cursor: pointer; }
.container { max-width: 920px; margin: 0 auto; padding: 0 22px 90px; }
.fade-in { animation: fadeUp .5s ease both; }
@keyframes fadeUp { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: none; } }
a { color: inherit; }

/* ===== 总览页 ===== */
.home-head { text-align: center; padding: 52px 0 10px; }
.home-head__seal {
  width: 64px; height: 64px; border: 2px solid var(--gold); border-radius: 8px; margin: 0 auto 20px;
  display: flex; align-items: center; justify-content: center;
  font-family: var(--kai); font-size: 34px; color: var(--gold-deep); transform: rotate(-3deg); background: var(--card);
  box-shadow: 0 6px 18px rgba(120, 95, 30, .12);
}
.home-head h1 { font-family: var(--kai); font-weight: 400; font-size: clamp(38px, 7vw, 58px); letter-spacing: .16em; color: var(--ink); text-indent: .16em; }
.home-head__sub { color: var(--text-dim); margin-top: 14px; letter-spacing: .08em; font-size: 15.5px; }
.home-head__slogan { color: var(--gold-deep); margin-top: 10px; font-size: 15px; letter-spacing: .2em; }

.unit { margin-top: 40px; }
.unit__head { display: flex; align-items: baseline; gap: 14px; border-bottom: 1px solid var(--line); padding-bottom: 10px; flex-wrap: wrap; }
.unit__no { font-family: var(--kai); font-size: 26px; color: var(--gold-deep); letter-spacing: .1em; }
.unit__theme { font-size: 16.5px; color: var(--ink); }
.unit__element { font-size: 13.5px; color: var(--text-dim); }
.lesson-row {
  display: flex; align-items: center; gap: 14px; padding: 15px 6px; border-bottom: 1px dashed var(--line);
  text-decoration: none; transition: background .2s ease; border-radius: 6px;
}
.lesson-row:hover { background: var(--card); }
.lesson-row.no-5 { padding: 11px 6px; }
.lesson-row__no {
  width: 34px; height: 34px; border-radius: 50%; border: 1.5px solid var(--gold); color: var(--gold-deep);
  display: flex; align-items: center; justify-content: center; font-size: 15px; flex: none; background: var(--card);
}
.lesson-row__no.star { border-radius: 8px; }
.lesson-row__title { font-size: 18px; color: var(--ink); }
.lesson-row__note { font-size: 13px; color: --text-dim; color: var(--text-dim); }
.lesson-row__type { font-size: 12.5px; color: var(--text-dim); border: 1px solid var(--line); border-radius: 4px; padding: 1px 7px; }
.lesson-row__state { margin-left: auto; font-size: 13.5px; letter-spacing: .06em; display: flex; align-items: center; gap: 6px; }
.state-pass { color: var(--green); }
.state-doing { color: var(--gold-deep); }
.state-wait { color: var(--text-dim); opacity: .7; }
.state-dots { display: inline-flex; gap: 4px; }
.state-dots i { width: 7px; height: 7px; border-radius: 50%; border: 1px solid var(--line); display: inline-block; }
.state-dots i.on { background: var(--green); border-color: var(--green); }

/* ===== 课文页 ===== */
.lesson-head { padding: 40px 0 6px; }
.lesson-head__back { color: var(--text-dim); text-decoration: none; font-size: 14.5px; letter-spacing: .1em; }
.lesson-head__back:hover { color: var(--gold); }
.lesson-head h1 { font-family: var(--kai); font-weight: 400; font-size: 44px; letter-spacing: .12em; color: var(--ink); margin: 14px 0 8px; }
.lesson-head__meta { display: flex; gap: 8px; flex-wrap: wrap; }
.chip { font-size: 12.5px; color: var(--gold-deep); border: 1px solid var(--line); background: var(--card); border-radius: 20px; padding: 3px 12px; }
.chip.dim { color: var(--text-dim); }

.rail { display: flex; gap: 10px; margin: 26px 0 8px; flex-wrap: wrap; }
.rail__step {
  flex: 1; min-width: 150px; border: 1px solid var(--line); background: var(--card); border-radius: 8px;
  padding: 12px 14px; text-align: left; transition: border-color .2s ease, transform .2s ease; font-family: var(--serif);
}
.rail__step:hover { border-color: var(--gold); transform: translateY(-2px); }
.rail__step.active { border-color: var(--gold); box-shadow: 0 0 0 1px var(--gold) inset; }
.rail__step .t { display: block; font-size: 16px; color: var(--ink); }
.rail__step .s { display: block; font-size: 12.5px; color: var(--text-dim); margin-top: 4px; }
.rail__step .ok { color: var(--green); font-size: 13px; float: right; }

.stage { margin-top: 30px; }
.stage__title { font-family: var(--kai); font-size: 26px; color: var(--ink); letter-spacing: .1em; margin-bottom: 6px; }
.stage__sub { color: var(--text-dim); font-size: 14.5px; margin-bottom: 22px; line-height: 1.8; }

/* 认字 */
.charcard-wrap { display: flex; flex-direction: column; align-items: center; }
.charcard {
  width: 240px; height: 300px; perspective: 900px; cursor: pointer; user-select: none;
}
.charcard__inner {
  width: 100%; height: 100%; position: relative; transform-style: preserve-3d; transition: transform .45s ease;
}
.charcard.flipped .charcard__inner { transform: rotateY(180deg); }
.charcard__face {
  position: absolute; inset: 0; backface-visibility: hidden; border-radius: 10px; border: 1px solid var(--line);
  background: var(--card); box-shadow: 0 10px 26px rgba(90, 72, 30, .1); display: flex; flex-direction: column;
  align-items: center; justify-content: center; padding: 20px;
}
.charcard__face--front .big { font-family: var(--kai); font-size: 130px; color: var(--ink); line-height: 1; }
.charcard__face--front .hint { font-size: 13px; color: var(--text-dim); margin-top: 18px; letter-spacing: .1em; }
.charcard__face--back { transform: rotateY(180deg); justify-content: flex-start; padding-top: 34px; gap: 14px; }
.charcard__face--back .py { font-size: 30px; color: var(--gold-deep); letter-spacing: .15em; }
.charcard__face--back .wd { font-size: 19px; color: var(--ink); }
.charcard__face--back .nt { font-size: 13px; color: var(--text-dim); line-height: 1.7; text-align: center; }
.charcard__face--back .lk { font-size: 12.5px; color: var(--gold); background: none; border: 1px dashed var(--gold); border-radius: 16px; padding: 3px 14px; }
.chars-progress { margin-top: 18px; color: var(--text-dim); font-size: 14px; letter-spacing: .08em; }
.char-actions { display: flex; gap: 14px; margin-top: 20px; }
.btn {
  border: 1px solid var(--line); background: var(--card); color: var(--ink); border-radius: 24px;
  padding: 10px 26px; font-size: 16px; letter-spacing: .08em; transition: all .2s ease;
}
.btn:hover { border-color: var(--gold); color: var(--gold-deep); }
.btn.primary { background: var(--gold); border-color: var(--gold); color: #fff; }
.btn.primary:hover { background: var(--gold-deep); }
.btn.green { border-color: var(--green); color: var(--green); }
.btn:disabled { opacity: .45; cursor: default; }
.pass-panel { text-align: center; padding: 46px 20px; border: 1px solid var(--line); border-radius: 12px; background: var(--card); }
.pass-panel .emoji { font-size: 44px; }
.pass-panel h3 { font-family: var(--kai); font-weight: 400; font-size: 28px; color: var(--green); margin: 14px 0 8px; letter-spacing: .15em; }
.pass-panel p { color: var(--text-dim); font-size: 15px; line-height: 2; }
.write-strip { margin-top: 26px; border: 1px dashed var(--line); border-radius: 10px; padding: 16px 18px; background: var(--paper-deep); }
.write-strip .cap { font-size: 13.5px; color: var(--gold-deep); letter-spacing: .15em; margin-bottom: 10px; }
.write-strip .chars { font-family: var(--kai); font-size: 30px; color: var(--ink); letter-spacing: .35em; line-height: 1.8; }
.write-strip .note { font-size: 12.5px; color: var(--text-dim); margin-top: 8px; }

/* 朗读 */
.read-imgs { display: flex; flex-direction: column; gap: 18px; align-items: center; }
.read-imgs img { width: 100%; max-width: 620px; border: 1px solid var(--line); border-radius: 6px; background: #fff; box-shadow: 0 8px 22px rgba(90, 72, 30, .1); }
.recite-note { font-size: 13.5px; color: var(--text-dim); line-height: 1.9; border-left: 3px solid var(--gold); padding: 2px 0 2px 14px; margin: 20px 0; }
.rec-box { margin-top: 26px; border: 1px solid var(--line); border-radius: 12px; background: var(--card); padding: 24px; text-align: center; }
.rec-box .row { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.rec-box audio { width: 100%; max-width: 420px; margin-top: 18px; }
.selfcheck { margin-top: 30px; text-align: center; }
.selfcheck .q { font-size: 16px; color: var(--ink); margin-bottom: 16px; letter-spacing: .05em; }
.selfcheck .row { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

/* 字音体检 */
.eval-cap { font-size: 15px; color: var(--gold-deep); letter-spacing: .15em; margin-bottom: 10px; }
.eval-text { font-family: var(--kai); font-size: 20px; color: var(--ink); line-height: 1.9; letter-spacing: .04em; }
.eval-note { font-size: 12.5px; color: var(--text-dim); line-height: 1.8; margin-top: 6px; }
.eval-result { margin-top: 16px; border-top: 1px dashed var(--line); padding-top: 14px; }
.eval-chars { font-family: var(--kai); font-size: 24px; line-height: 2; letter-spacing: .12em; }
.evc { color: var(--green); }
.evc.bad { color: #b3413a; border-bottom: 2px dotted #b3413a; }
.evc-btn { font-family: var(--kai); font-size: 17px; color: #b3413a; background: none; border: 1px solid #b3413a; border-radius: 6px; padding: 1px 8px; margin: 0 2px; }
.evc-btn:hover { background: rgba(179, 65, 58, .08); }

/* 聊聊 */
.chat-box { border: 1px solid var(--line); border-radius: 12px; background: var(--card); overflow: hidden; }
.chat-list { padding: 18px; max-height: 460px; overflow-y: auto; display: flex; flex-direction: column; gap: 14px; }
.msg { max-width: 82%; padding: 10px 16px; border-radius: 14px; font-size: 15.5px; line-height: 1.8; white-space: pre-wrap; }
.msg.duoduo { align-self: flex-end; background: var(--paper-deep); border-bottom-right-radius: 4px; }
.msg.momo { align-self: flex-start; background: #fff; border: 1px solid var(--line); border-bottom-left-radius: 4px; position: relative; }
.msg .voice { display: inline-flex; align-items: center; gap: 5px; margin-left: 10px; color: var(--gold); background: none; border: none; font-size: 13px; }
.chat-input { display: flex; gap: 10px; padding: 12px; border-top: 1px solid var(--line); background: var(--paper-deep); }
.chat-input input { flex: 1; border: 1px solid var(--line); border-radius: 22px; padding: 10px 18px; font-family: var(--serif); font-size: 16px; background: #fff; outline: none; }
.chat-input input:focus { border-color: var(--gold); }
.starters { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 14px; }
.starter { border: 1px dashed var(--gold); color: var(--gold-deep); background: none; border-radius: 20px; padding: 7px 16px; font-size: 14px; }
.starter:hover { background: rgba(154, 123, 28, .07); }

/* 谈资 */
.tip-seeds { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 20px; }
.tip-card { border: 1px solid var(--line); border-left: 4px solid var(--gold); border-radius: 10px; background: var(--card); padding: 22px 24px; }
.tip-card .cap { font-size: 13px; color: var(--gold-deep); letter-spacing: .15em; margin-bottom: 12px; display: flex; align-items: center; gap: 10px; }
.tip-card .body { font-size: 16.5px; line-height: 2.05; color: var(--ink); white-space: pre-wrap; }
.tip-card .ops { margin-top: 16px; display: flex; gap: 10px; flex-wrap: wrap; }
.tip-history { margin-top: 34px; }
.tip-history h4 { font-size: 15px; color: var(--text-dim); letter-spacing: .15em; margin-bottom: 6px; font-weight: 400; }
.tip-history .item { border-bottom: 1px dashed var(--line); padding: 13px 2px; display: flex; gap: 12px; align-items: baseline; }
.tip-history .lb { font-size: 13px; color: var(--gold-deep); flex: none; }
.tip-history .tx { font-size: 14px; color: var(--text-dim); line-height: 1.7; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }

.stage-nav { display: flex; justify-content: space-between; margin-top: 44px; gap: 12px; }
.stage-nav .btn { display: inline-flex; align-items: center; gap: 7px; }

.footer { text-align: center; margin-top: 70px; font-size: 13px; letter-spacing: .2em; color: var(--text-dim); }
.footer a { color: var(--text-dim); text-decoration: none; }
.footer a:hover { color: var(--gold); }
.loading { text-align: center; color: var(--text-dim); padding: 80px 0; letter-spacing: .2em; }
.err { color: #a33; }

/* 词语卡 */
.charcard__face--front .big.wd { font-size: 56px; letter-spacing: .06em; }

/* 谈资卡主图（课文级，压缩入库 ≤160KB） */
.tip-img { width: 100%; height: 210px; object-fit: cover; border-radius: 8px 8px 0 0; margin: -22px -24px 14px; width: calc(100% + 48px); display: block; }
.tip-card { overflow: hidden; }