:root {
  --accent: #168579;
  --accent-dark: #0f675f;
  --ok: #177b58;
  --bad: #d95745;
  --bg: #f6f3ed;
  --card: #fffdfa;
  --text: #142238;
  --muted: #6c7887;
  --line: rgba(20, 34, 56, .13);
  --coral: #ff6b4a;
}

body {
  min-height: 100vh;
  color: var(--text);
  background:
    radial-gradient(circle at 92% 0%, rgba(41, 161, 148, .14), transparent 31rem),
    linear-gradient(180deg, #edf4f1 0, var(--bg) 24rem);
  font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
}

header {
  position: relative;
  overflow: hidden;
  min-height: 106px;
  padding: 22px clamp(20px, 5vw, 64px);
  background: linear-gradient(112deg, #142238, #17394a 68%, #17685f);
  box-shadow: 0 12px 32px rgba(20, 34, 56, .18);
}
header::after {
  content: "LS";
  position: absolute;
  right: clamp(20px, 5vw, 64px);
  top: -44px;
  color: rgba(255,255,255,.06);
  font: 900 170px/1 Georgia, serif;
  pointer-events: none;
}
header h1 { position: relative; z-index: 1; font: 800 clamp(25px, 3.2vw, 38px)/1.1 Georgia, "Noto Serif SC", "Songti SC", serif; letter-spacing: -.035em; }
.stats { position: relative; z-index: 1; gap: 11px; font-size: 12px; }
.stats span { padding: 6px 9px; border: 1px solid rgba(255,255,255,.13); border-radius: 999px; background: rgba(255,255,255,.07); }
.stats b { color: #99e6dd; }

main { max-width: 840px; padding: clamp(30px, 5vw, 58px) 20px 80px; }
.panel, .card { border: 1px solid var(--line); border-radius: 22px; background: rgba(255,253,250,.96); box-shadow: 0 20px 48px rgba(20,34,56,.09); }
.panel { padding: clamp(24px, 4vw, 42px); }
.card { padding: clamp(24px, 4vw, 42px); }
h2 { margin: 25px 0 11px; color: var(--text); font: 800 24px/1.2 Georgia, "Noto Serif SC", "Songti SC", serif; letter-spacing: -.025em; }
h2:first-child { margin-top: 0; }
.chips { gap: 9px; }
.chip { border: 1px solid var(--line); padding: 9px 17px; border-radius: 999px; color: var(--text); background: #fffdfa; font-size: 13px; font-weight: 700; }
.chip:hover { border-color: var(--accent); color: var(--accent-dark); }
.chip.on { border-color: var(--accent); background: var(--accent); color: #fff; box-shadow: 0 5px 13px rgba(22,133,121,.22); }
.btn { border-radius: 11px; padding: 12px 22px; background: var(--accent); font-size: 14px; font-weight: 800; box-shadow: 0 8px 16px rgba(22,133,121,.18); }
.btn:hover { background: var(--accent-dark); }
.btn.secondary { color: var(--accent-dark); background: #e7f5f1; box-shadow: none; }
.btn.secondary:hover { background: #d8ece6; }
.btn.warn { background: var(--coral); }
.btn.warn:hover { background: #e85b3e; }
.btn:disabled { background: #b4c1c6; box-shadow: none; }
.btn.big { margin-top: 19px; padding: 14px; font-size: 15px; }

.progress-bar { height: 8px; margin-bottom: 18px; background: #dfe7e5; }
.progress-bar > div { background: linear-gradient(90deg, var(--accent), #3aada0); }
.meta { gap: 7px; margin-bottom: 20px; }
.tag { padding: 5px 10px; color: var(--accent-dark); background: #e8f5f1; font-size: 11px; font-weight: 800; }
.tag.level-高频 { color: #955212; background: #fff0ca; }
.tag.level-次高频 { color: #17685f; background: #dff2ed; }
.tag.level-非高频 { color: #667583; background: #eef1f2; }
.sentence { font: 500 clamp(18px, 2.7vw, 22px)/1.8 Georgia, "Times New Roman", serif; }
.blank { border-color: var(--accent); color: var(--accent); }
.speak-row { margin-bottom: 20px; padding: 12px 14px; border-radius: 14px; background: #f2f6f4; }
.speak-btn { width: 44px; height: 44px; background: var(--accent); box-shadow: 0 6px 13px rgba(22,133,121,.2); }
.speak-btn:hover { background: var(--accent-dark); }
#spellInput { border-color: #c4d4d1; background: #fff; font: 600 19px/1.2 Georgia, "Times New Roman", serif; }
#spellInput:focus { border-color: var(--accent); box-shadow: 0 0 0 4px rgba(22,133,121,.12); }
#spellInput.good { border-color: var(--ok); background: #eff9f4; }
#spellInput.bad { border-color: var(--bad); background: #fff2f0; }
.result-msg { font-weight: 700; }
.back-word { color: var(--text); font: 800 31px/1.15 Georgia, "Times New Roman", serif; }
.meaning { color: #495969; }
.meaning b { color: var(--accent-dark); }
.penalty { border-color: #e3c6bf; }
.penalty h3 { color: var(--bad); }
.penalty-inputs input { border-color: #e5beb6; background: #fffaf8; }
.penalty-inputs input:focus { border-color: var(--bad); }
.wrong-list li { border-color: #e6e9e9; }
.count-pill { background: var(--coral); }

@media (max-width: 560px) {
  header { min-height: 124px; align-items: flex-start; }
  header h1 { max-width: 260px; font-size: 27px; }
  .stats { gap: 6px; }
  .stats span { padding: 5px 7px; }
  .type-row { flex-wrap: wrap; }
  #spellInput { width: 100%; flex-basis: 100%; }
  .type-row .btn { flex: 1; }
  .nav-row { flex-direction: column; }
}