:root {
  --paper: #f4efe4;
  --card: #fffdf8;
  --ink: #1b2620;
  --muted: #6d7a72;
  --line: #e2dccd;
  --accent: #1f5c46;
  --accent-soft: #e2eee7;
  --gold: #d99a2b;
  --gold-soft: #fbefd6;
  --red: #b8432b;
  --red-soft: #f8e3dc;
  --serif: 'Fraunces', Georgia, 'Songti SC', serif;
  --sans: 'Instrument Sans', -apple-system, 'PingFang SC', 'Hiragino Sans GB', sans-serif;
  --radius: 16px;
}
* { box-sizing: border-box; }
html, body { margin: 0; background: var(--paper); color: var(--ink); font: 16px/1.6 var(--sans); -webkit-font-smoothing: antialiased; }
body { background-image: radial-gradient(circle at 15% -10%, #fbf7ee 0, transparent 50%), radial-gradient(circle at 110% 30%, #efe7d6 0, transparent 40%); min-height: 100vh; }
.hidden { display: none !important; }
button, input, textarea, select { font: inherit; color: inherit; }
a { color: var(--accent); }

.brand { font-family: var(--serif); font-style: italic; font-weight: 600; font-size: 26px; letter-spacing: -0.5px; color: var(--accent); }
.brand span { color: var(--gold); }
.brand.big { font-size: 52px; line-height: 1; margin-bottom: 6px; }

/* layout */
.top { position: sticky; top: 0; z-index: 10; display: flex; align-items: center; gap: 28px; padding: 14px 28px; background: rgba(244, 239, 228, .88); backdrop-filter: blur(10px); border-bottom: 1px solid var(--line); }
#nav { display: flex; gap: 4px; }
#nav a { position: relative; padding: 7px 14px; border-radius: 99px; cursor: pointer; color: var(--muted); text-decoration: none; font-weight: 500; user-select: none; }
#nav a:hover { color: var(--ink); }
#nav a.on { background: var(--ink); color: var(--paper); }
.badge { position: absolute; top: -2px; right: -4px; min-width: 18px; height: 18px; padding: 0 5px; border-radius: 9px; background: var(--gold); color: #fff; font: 600 11px/18px var(--sans); text-align: center; }
main { max-width: 860px; margin: 0 auto; padding: 28px 20px 120px; }
@media (max-width: 720px) {
  .top { padding: 10px 16px; }
  #nav { position: fixed; bottom: 0; left: 0; right: 0; justify-content: space-around; padding: 8px 6px calc(8px + env(safe-area-inset-bottom)); background: var(--card); border-top: 1px solid var(--line); }
  #nav a { padding: 6px 10px; font-size: 14px; }
  main { padding: 18px 14px 110px; }
}

/* type */
h1 { font: 600 36px/1.15 var(--serif); letter-spacing: -0.8px; margin: 0 0 6px; }
h2 { font: 600 24px/1.2 var(--serif); letter-spacing: -0.4px; margin: 0 0 12px; }
h3 { font: 600 17px/1.3 var(--sans); margin: 0 0 8px; }
.muted { color: var(--muted); }
.small { font-size: 14px; }
.en { font-family: var(--serif); font-size: 19px; line-height: 1.5; }
.kicker { font: 600 12px/1 var(--sans); letter-spacing: 1.4px; text-transform: uppercase; color: var(--gold); margin-bottom: 8px; }
.err { color: var(--red); min-height: 1em; }

/* surfaces */
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; margin-bottom: 16px; box-shadow: 0 1px 0 rgba(0,0,0,.02), 0 8px 24px -16px rgba(40, 50, 30, .25); }
.card.flat { box-shadow: none; }
.row { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
.row.between { justify-content: space-between; }
.grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.grid4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
@media (max-width: 720px) { .grid2 { grid-template-columns: 1fr; } .grid4 { grid-template-columns: 1fr 1fr; } }
.sep { height: 1px; background: var(--line); margin: 16px 0; }

/* controls */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 6px; padding: 9px 18px; border-radius: 99px; border: 1px solid var(--line); background: var(--card); cursor: pointer; font-weight: 500; transition: transform .08s, background .15s; white-space: nowrap; }
.btn:hover { background: #f7f2e7; }
.btn:active { transform: scale(.97); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover { background: #184a38; }
.btn.gold { background: var(--gold); border-color: var(--gold); color: #fff; }
.btn.ghost { background: transparent; border-color: transparent; color: var(--muted); }
.btn.sm { padding: 5px 12px; font-size: 14px; }
.btn.wide { width: 100%; }
.btn:disabled { opacity: .5; cursor: default; }
.btn.added { background: var(--accent-soft); border-color: var(--accent-soft); color: var(--accent); }
.icon-btn { width: 38px; height: 38px; padding: 0; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; border: 1px solid var(--line); background: var(--card); cursor: pointer; font-size: 16px; flex: none; }
.icon-btn:hover { background: var(--accent-soft); }
input, textarea, select { width: 100%; padding: 11px 14px; border: 1px solid var(--line); border-radius: 12px; background: #fff; outline: none; }
input:focus, textarea:focus, select:focus { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
textarea { min-height: 130px; resize: vertical; font-family: var(--serif); font-size: 18px; line-height: 1.55; }
label { display: block; font-size: 14px; color: var(--muted); margin: 12px 0 4px; }
.tabs { display: inline-flex; gap: 4px; padding: 4px; background: #ebe4d4; border-radius: 99px; margin-bottom: 18px; flex-wrap: wrap; }
.tabs button { border: 0; background: transparent; padding: 7px 16px; border-radius: 99px; cursor: pointer; color: var(--muted); font-weight: 500; }
.tabs button.on { background: var(--card); color: var(--ink); box-shadow: 0 1px 3px rgba(0,0,0,.08); }

/* login */
.login { min-height: 100vh; display: grid; place-items: center; padding: 20px; }
.login-card { width: 100%; max-width: 360px; display: grid; gap: 12px; }

/* today */
.hero { display: flex; justify-content: space-between; align-items: flex-end; gap: 20px; margin-bottom: 22px; flex-wrap: wrap; }
.streak { text-align: right; }
.streak b { font: 600 52px/1 var(--serif); color: var(--gold); }
.goal { cursor: pointer; padding: 16px; border-radius: 14px; background: var(--card); border: 1px solid var(--line); transition: transform .1s; }
.goal:hover { transform: translateY(-2px); }
.goal .num { font: 600 28px/1.1 var(--serif); }
.goal .bar { height: 5px; border-radius: 3px; background: var(--line); margin-top: 10px; overflow: hidden; }
.goal .bar i { display: block; height: 100%; background: var(--accent); border-radius: 3px; }
.goal.done { background: var(--accent-soft); border-color: #c5ddd0; }
.heat { display: grid; grid-auto-flow: column; grid-template-rows: repeat(7, 13px); grid-auto-columns: 13px; gap: 3px; overflow-x: auto; padding-bottom: 4px; }
.heat i { width: 13px; height: 13px; border-radius: 3px; background: #e9e3d4; }
.heat i[data-l="1"] { background: #bcd8c8; } .heat i[data-l="2"] { background: #7fb39a; } .heat i[data-l="3"] { background: #3f8366; } .heat i[data-l="4"] { background: var(--accent); }

/* vocab */
.word-head { display: flex; align-items: baseline; gap: 12px; flex-wrap: wrap; }
.word-head .w { font: 600 30px/1.1 var(--serif); letter-spacing: -0.5px; }
.ipa { color: var(--muted); font-family: 'Lucida Grande', var(--sans); }
.pos { font-size: 13px; padding: 2px 9px; border-radius: 99px; background: var(--gold-soft); color: #8a5d12; }
.ex { padding: 10px 14px; border-left: 3px solid var(--gold); background: #fbf8f1; border-radius: 0 10px 10px 0; margin: 8px 0; }
.ex .en { font-size: 17px; }
.chips { display: flex; gap: 6px; flex-wrap: wrap; }
.chip { padding: 3px 11px; border-radius: 99px; background: var(--accent-soft); color: var(--accent); font-size: 14px; }
.tip { padding: 12px 14px; border-radius: 12px; background: var(--gold-soft); font-size: 15px; }
.tip::before { content: '💡 '; }
.collapsed .more { display: none; }
.word-card { cursor: default; }

/* express */
.score { font: 600 46px/1 var(--serif); }
.score small { font-size: 16px; color: var(--muted); font-family: var(--sans); }
.score.good { color: var(--accent); } .score.mid { color: var(--gold); } .score.bad { color: var(--red); }
.issue { display: grid; grid-template-columns: 1fr auto; gap: 6px 12px; padding: 12px 0; border-top: 1px dashed var(--line); }
.issue:first-child { border-top: 0; }
.del { color: var(--red); text-decoration: line-through; text-decoration-color: rgba(184,67,43,.5); }
.ins { color: var(--accent); font-weight: 600; }
.tag { font-size: 12px; padding: 1px 8px; border-radius: 99px; background: #ece6d8; color: var(--muted); margin-left: 6px; }
.natural { padding: 16px 18px; border-radius: 14px; background: var(--accent-soft); }
.chat { display: flex; flex-direction: column; gap: 10px; max-height: 58vh; overflow-y: auto; padding: 4px 2px 10px; }
.bubble { max-width: 84%; padding: 10px 14px; border-radius: 18px; font-family: var(--serif); font-size: 17px; line-height: 1.45; }
.bubble.ai { align-self: flex-start; background: var(--card); border: 1px solid var(--line); border-bottom-left-radius: 6px; }
.bubble.me { align-self: flex-end; background: var(--ink); color: var(--paper); border-bottom-right-radius: 6px; }
.fb { align-self: flex-end; max-width: 84%; font-size: 14px; padding: 8px 12px; border-radius: 12px; }
.fb.ok { background: var(--accent-soft); } .fb.fix { background: var(--gold-soft); }

/* speak */
.sent-list { display: grid; gap: 8px; }
.sent { padding: 12px 16px; border-radius: 12px; border: 1px solid var(--line); background: var(--card); cursor: pointer; display: flex; justify-content: space-between; gap: 12px; align-items: center; }
.sent.on { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
.sent .best { font-weight: 600; font-size: 14px; }
.target { font: 400 27px/1.45 var(--serif); letter-spacing: -0.2px; }
.target .wok { color: var(--accent); } .target .wbad { color: var(--red); text-decoration: underline wavy rgba(184,67,43,.5); text-underline-offset: 5px; }
.mic { width: 76px; height: 76px; border-radius: 50%; border: 0; background: var(--red); color: #fff; font-size: 28px; cursor: pointer; box-shadow: 0 8px 20px -8px rgba(184,67,43,.7); flex: none; }
.mic.rec { animation: pulse 1.1s infinite; background: #8f2a17; }
@keyframes pulse { 0% { box-shadow: 0 0 0 0 rgba(184,67,43,.55); } 70% { box-shadow: 0 0 0 18px rgba(184,67,43,0); } 100% { box-shadow: 0 0 0 0 rgba(184,67,43,0); } }

/* review */
.flash { min-height: 300px; display: flex; flex-direction: column; }
.flash .front { flex: 1; display: flex; flex-direction: column; justify-content: center; align-items: center; text-align: center; gap: 10px; padding: 20px 0; }
.flash .front .w { font: 600 40px/1.15 var(--serif); letter-spacing: -0.8px; }
.grades { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; margin-top: 16px; }
.grades .btn { flex-direction: column; gap: 0; padding: 10px 6px; border-radius: 14px; }
.grades .btn small { font-size: 12px; opacity: .75; }
.g0 { color: var(--red); } .g1 { color: #9a6a12; } .g2 { color: var(--accent); } .g3 { color: #2a5d8f; }
.progress { height: 6px; border-radius: 3px; background: var(--line); overflow: hidden; margin-bottom: 16px; }
.progress i { display: block; height: 100%; background: var(--gold); transition: width .3s; }

/* misc */
.toast { position: fixed; left: 50%; bottom: 90px; transform: translateX(-50%) translateY(20px); background: var(--ink); color: var(--paper); padding: 10px 18px; border-radius: 99px; opacity: 0; transition: all .25s; pointer-events: none; z-index: 50; font-size: 15px; }
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
.loading { display: flex; align-items: center; gap: 12px; color: var(--muted); padding: 28px 0; justify-content: center; }
.loading::before { content: ''; width: 18px; height: 18px; border-radius: 50%; border: 2px solid var(--line); border-top-color: var(--accent); animation: spin .8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
.empty { text-align: center; padding: 40px 10px; color: var(--muted); }
.empty .big { font-size: 46px; }
table.lib { width: 100%; border-collapse: collapse; font-size: 15px; }
table.lib td { padding: 9px 6px; border-top: 1px solid var(--line); vertical-align: top; }
.fade-in { animation: fadein .25s ease; }
@keyframes fadein { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }