:root{
  --accent:#325aaf;
  --accent-dark:#274890;
  --bg:#f2f4f8;
  --card:#ffffff;
  --text:#1b2a3a;
  --muted:#7a8699;
  --line-thin:#c7d0dc;
  --line-thick:#344861;
  --given:#22303f;
  --player:#325aaf;
  --wrong:#e23b3b;
  --hint:#0f9d58;
  --peer:#e7ecf5;
  --same:#cfe0f8;
  --selected:#a9c7f2;
  --danger:#e23b3b;
  --shadow:0 6px 20px rgba(28,45,80,.12);
  --radius:14px;
}

*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;height:100%}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  background:var(--bg);color:var(--text);
  overscroll-behavior:none;
  -webkit-user-select:none;user-select:none;
}
#app{height:100%}

/* ---------- screens ---------- */
.screen{
  display:none;flex-direction:column;
  height:100dvh;height:100vh;
  padding:calc(env(safe-area-inset-top) + 8px) 12px calc(env(safe-area-inset-bottom) + 10px);
  max-width:520px;margin:0 auto;
}
.screen.active{display:flex}

.topbar{display:flex;align-items:center;gap:8px;margin-bottom:8px}
.topbar h2{font-size:18px;margin:0;font-weight:600}
.topbar .spacer{width:40px}
.icon-btn{
  width:40px;height:40px;border:none;background:transparent;color:var(--text);
  font-size:26px;line-height:1;border-radius:10px;cursor:pointer;flex:0 0 auto;
}
.icon-btn:active{background:#e6ebf3}

/* ---------- home ---------- */
.home-inner{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:36px}
.brand{display:flex;flex-direction:column;align-items:center;gap:16px}
.brand-mark{
  display:grid;grid-template-columns:repeat(3,1fr);width:96px;height:96px;
  background:var(--accent);border-radius:20px;overflow:hidden;box-shadow:var(--shadow);
  color:#fff;font-weight:700;
}
.brand-mark span{display:flex;align-items:center;justify-content:center;font-size:22px;
  border-right:1px solid rgba(255,255,255,.25);border-bottom:1px solid rgba(255,255,255,.25)}
.brand h1{margin:0;font-size:38px;letter-spacing:.5px;font-weight:800;color:var(--accent)}
.home-buttons{display:flex;flex-direction:column;gap:12px;width:100%;max-width:320px}

.btn{
  border:none;border-radius:var(--radius);padding:15px 18px;font-size:17px;font-weight:600;
  cursor:pointer;width:100%;transition:transform .04s ease, background .15s;
}
.btn:active{transform:scale(.985)}
.btn-primary{background:var(--accent);color:#fff;box-shadow:var(--shadow)}
.btn-primary:active{background:var(--accent-dark)}
.btn-secondary{background:var(--card);color:var(--accent);box-shadow:var(--shadow)}
.btn-text{background:transparent;color:var(--muted);box-shadow:none;font-weight:500}
.btn-continue{display:flex;flex-direction:column;align-items:flex-start;gap:2px}
.btn-continue .btn-title{font-size:17px}
.btn-continue .btn-sub{font-size:13px;font-weight:400;opacity:.85}
.dot{display:inline-block;width:9px;height:9px;border-radius:50%;background:#f4b400;margin-left:6px;vertical-align:middle}

/* ---------- difficulty ---------- */
.diff-list{display:flex;flex-direction:column;gap:12px;padding-top:8px}
.diff-btn{
  display:flex;justify-content:space-between;align-items:center;
  background:var(--card);border:none;border-radius:var(--radius);padding:18px 20px;
  box-shadow:var(--shadow);cursor:pointer;
}
.diff-btn:active{transform:scale(.99)}
.diff-name{font-size:18px;font-weight:600;color:var(--text)}
.diff-best{font-size:13px;color:var(--muted)}

/* ---------- game ---------- */
.game-top{display:flex;align-items:center;gap:6px;margin-bottom:10px}
.game-meta{flex:1;display:flex;justify-content:space-between;gap:4px}
.meta-block{display:flex;flex-direction:column;align-items:center;min-width:52px}
.meta-label{font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.4px}
.meta-val{font-size:17px;font-weight:700;margin-top:2px}

.board-wrap{display:flex;justify-content:center;align-items:center;margin:2px 0 14px}
.board{
  width:min(94vw,460px);aspect-ratio:1/1;display:grid;
  grid-template-columns:repeat(9,1fr);grid-template-rows:repeat(9,1fr);
  background:#fff;border:2px solid var(--line-thick);border-radius:6px;overflow:hidden;
}
.cell{
  position:relative;display:flex;align-items:center;justify-content:center;
  background:#fff;cursor:pointer;
  border-top:1px solid var(--line-thin);border-left:1px solid var(--line-thin);
}
.cell.bt{border-top:2px solid var(--line-thick)}
.cell.bl{border-left:2px solid var(--line-thick)}
.cell.br{border-right:2px solid var(--line-thick)}
.cell.bb{border-bottom:2px solid var(--line-thick)}

.cell.peer{background:var(--peer)}
.cell.same{background:var(--same)}
.cell.selected{background:var(--selected)}

.cell .val{font-size:clamp(20px,6.2vw,30px);font-weight:500;color:var(--player);line-height:1}
.cell.given .val{color:var(--given);font-weight:600}
.cell.wrong .val{color:var(--wrong);font-weight:600}
.cell.hinted .val{color:var(--hint);font-weight:700}

.cell .notes{
  position:absolute;inset:2px;display:none;
  grid-template-columns:repeat(3,1fr);grid-template-rows:repeat(3,1fr);
  pointer-events:none;
}
.cell.has-notes .notes{display:grid}
.cell .note{font-size:clamp(8px,2.4vw,11px);color:var(--muted);display:flex;align-items:center;justify-content:center;line-height:1}

/* ---------- tools ---------- */
.controls{display:flex;justify-content:space-around;gap:6px;margin-bottom:12px}
.tool{
  position:relative;flex:1;background:transparent;border:none;cursor:pointer;
  display:flex;flex-direction:column;align-items:center;gap:4px;color:var(--muted);padding:6px 0;
}
.tool-ico{
  width:46px;height:46px;border-radius:50%;background:var(--card);box-shadow:var(--shadow);
  display:flex;align-items:center;justify-content:center;font-size:20px;color:var(--accent);
}
.tool:active .tool-ico{background:#eef2f8}
.tool-lbl{font-size:12px}
.tool.active .tool-ico{background:var(--accent);color:#fff}
.tool.disabled{opacity:.4;pointer-events:none}
.tool-badge{
  position:absolute;top:0;right:calc(50% - 30px);background:#f4b400;color:#fff;
  font-size:11px;font-weight:700;min-width:18px;height:18px;border-radius:9px;
  display:flex;align-items:center;justify-content:center;padding:0 4px;
}

/* ---------- numpad ---------- */
.numpad{display:grid;grid-template-columns:repeat(9,1fr);gap:5px}
.num{
  position:relative;background:var(--card);border:none;border-radius:10px;
  padding:12px 0 8px;cursor:pointer;box-shadow:0 2px 8px rgba(28,45,80,.08);
  display:flex;flex-direction:column;align-items:center;
}
.num:active{transform:scale(.95);background:#eef2f8}
.num .digit{font-size:clamp(20px,6vw,28px);font-weight:600;color:var(--accent);line-height:1}
.num .count{font-size:10px;color:var(--muted);height:12px;margin-top:3px}
.num.done{opacity:.32;pointer-events:none}

/* ---------- stats ---------- */
.stats-body,.daily-body{overflow-y:auto;flex:1;padding-bottom:10px}
.streak-cards{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin:6px 0 18px}
.streak-card{background:var(--card);border-radius:12px;box-shadow:var(--shadow);
  padding:14px 6px;display:flex;flex-direction:column;align-items:center;gap:4px}
.sc-num{font-size:26px;font-weight:800;color:var(--accent)}
.sc-lbl{font-size:11px;color:var(--muted);text-align:center}
.table-wrap{background:var(--card);border-radius:14px;box-shadow:var(--shadow);overflow:hidden}
.stats-table{width:100%;border-collapse:collapse;font-size:14px}
.stats-table th,.stats-table td{padding:12px 6px;text-align:center}
.stats-table th{background:#eef2f8;color:var(--muted);font-weight:600;font-size:12px}
.stats-table td.l,.stats-table th.l{text-align:left;padding-left:16px;font-weight:600}
.stats-table tbody tr:not(:last-child){border-bottom:1px solid #eef1f6}

/* ---------- daily ---------- */
.daily-card{background:var(--card);border-radius:16px;box-shadow:var(--shadow);
  padding:22px;display:flex;flex-direction:column;gap:12px;align-items:center;text-align:center;margin-bottom:16px}
.daily-date{font-size:20px;font-weight:700}
.daily-diff-row{color:var(--muted);font-size:15px}
.daily-status{font-size:14px;color:var(--muted);padding:6px 0}
.daily-status.done{color:var(--hint);font-weight:600}
.daily-card .btn{max-width:280px}
.streak-cards.two,.daily-body .streak-cards{grid-template-columns:repeat(2,1fr)}

/* ---------- settings ---------- */
.settings-body{overflow-y:auto;flex:1;padding-bottom:12px;display:flex;flex-direction:column;gap:14px}
.settings-card{background:var(--card);border-radius:14px;box-shadow:var(--shadow);padding:16px 18px;display:flex;flex-direction:column;gap:10px}
.settings-row{display:flex;align-items:center;justify-content:space-between;gap:12px}
.settings-title{font-size:16px;font-weight:600}
.settings-sub{font-size:13px;color:var(--muted);line-height:1.4}
.settings-foot{font-size:12px;color:var(--muted);text-align:center;padding:0 8px;line-height:1.5}
.stats-note{font-size:12px;color:var(--muted);text-align:center;margin:14px 4px 0;line-height:1.5}
.dot-blue{background:var(--accent)}

.switch{width:52px;height:30px;border-radius:16px;background:#cbd3df;border:none;position:relative;cursor:pointer;flex:0 0 auto;transition:background .18s;padding:0}
.switch .knob{position:absolute;top:3px;left:3px;width:24px;height:24px;border-radius:50%;background:#fff;box-shadow:0 1px 3px rgba(0,0,0,.25);transition:left .18s}
.switch.on{background:var(--accent)}
.switch.on .knob{left:25px}

.settings-card .btn{margin-top:4px}
.sync-or{font-size:12px;color:var(--muted);text-align:center;margin:10px 0 6px}
.sync-link-row{display:flex;gap:8px}
.sync-input{flex:1;min-width:0;border:1px solid var(--line-thin);border-radius:10px;padding:12px;font-size:16px;
  letter-spacing:2px;text-transform:uppercase;text-align:center;background:#fff;color:var(--text)}
.sync-input:focus{outline:none;border-color:var(--accent)}
.sync-link-btn{width:auto;padding-left:22px;padding-right:22px}

.sync-code-display{background:#eef2f8;border-radius:12px;padding:14px;display:flex;flex-direction:column;gap:6px;margin:6px 0}
.sync-code-label{font-size:12px;color:var(--muted);text-transform:uppercase;letter-spacing:.5px}
.sync-code-value{display:flex;align-items:center;gap:10px}
#sync-code-text{font-size:24px;font-weight:800;letter-spacing:3px;color:var(--accent)}
.mini-btn{border:none;background:var(--accent);color:#fff;border-radius:8px;padding:6px 12px;font-size:13px;font-weight:600;cursor:pointer}
.sync-actions{display:flex;flex-direction:column;gap:6px;margin-top:6px}

/* ---------- overlays ---------- */
.overlay{
  position:fixed;inset:0;z-index:50;display:none;
  align-items:center;justify-content:center;flex-direction:column;gap:14px;
  background:rgba(20,32,54,.45);backdrop-filter:blur(4px);-webkit-backdrop-filter:blur(4px);
  color:#fff;padding:20px;
}
.overlay.show{display:flex}
.spinner{width:44px;height:44px;border:4px solid rgba(255,255,255,.35);border-top-color:#fff;border-radius:50%;animation:spin .8s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}

.pause-card,.win-card{
  background:var(--card);color:var(--text);border-radius:20px;box-shadow:var(--shadow);
  padding:26px 22px;width:100%;max-width:340px;text-align:center;
  display:flex;flex-direction:column;gap:14px;align-items:center;
}
.pause-icon{font-size:40px;color:var(--accent)}
.pause-card h3,.win-card h3{margin:0;font-size:22px}
.pause-card .btn,.win-card .btn{max-width:260px}

.confetti{position:fixed;inset:0;width:100%;height:100%;pointer-events:none;z-index:51}
.win-card{position:relative;z-index:52}
.win-badge{background:#fdf1cf;color:#8a6d00;font-weight:700;font-size:13px;padding:6px 12px;border-radius:20px}
.win-score-big{display:flex;flex-direction:column;gap:2px}
.win-score-big #win-score{font-size:46px;font-weight:800;color:var(--accent);line-height:1}
.wsb-lbl{font-size:13px;color:var(--muted)}
.win-rows{width:100%;display:flex;flex-direction:column;gap:8px;margin-top:4px}
.win-row{display:flex;justify-content:space-between;font-size:15px;padding:2px 4px}
.win-row span:first-child{color:var(--muted)}
.win-row span:last-child{font-weight:600}
.win-actions{display:flex;flex-direction:column;gap:6px;width:100%;margin-top:6px}