:root{
  color-scheme:light;
  --bg:#fffaf5;
  --card:#ffffff;
  --ink:#3d4050;
  --muted:#777b8b;
  --line:#e8e4f3;
  --purple:#8f7cf6;
  --purple-soft:#eee9ff;
  --pink:#f3a9bb;
  --yellow:#f7d86f;
  --green:#9edda6;
  --shadow:0 14px 40px rgba(92,77,137,.12);
}
*{box-sizing:border-box}
html{background:var(--bg)}
body{
  margin:0;
  min-height:100vh;
  color:var(--ink);
  background:
    radial-gradient(circle at 8% 8%,rgba(247,216,111,.24),transparent 25%),
    radial-gradient(circle at 92% 5%,rgba(243,169,187,.18),transparent 24%),
    var(--bg);
  font-family:"Hiragino Kaku Gothic ProN","Yu Gothic","Meiryo",sans-serif;
}
button,a{font:inherit}
button{color:inherit}
.playground-shell{width:min(1180px,100%);margin:0 auto;padding:20px 22px 32px}
.playground-header{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:18px}
.brand-row{display:flex;align-items:center;gap:10px}.brand-mark{display:grid;place-items:center;width:44px;height:44px;border-radius:15px;background:var(--purple-soft);font-size:24px}.brand-name{font-size:26px;font-weight:900;letter-spacing:.04em}.brand-sub{margin:3px 0 0 54px;color:var(--muted);font-weight:700}
.header-links{display:flex;gap:8px;flex-wrap:wrap;justify-content:flex-end}.header-links a{text-decoration:none;color:#5f5a72;background:#fff;border:1px solid var(--line);padding:10px 14px;border-radius:999px;font-weight:800;box-shadow:0 5px 16px rgba(74,65,105,.05)}
.category-tabs{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-bottom:18px}.category-tab{border:2px solid transparent;background:#fff;border-radius:18px;padding:15px 12px;font-size:18px;font-weight:900;cursor:pointer;box-shadow:0 7px 22px rgba(80,67,124,.07);transition:.18s ease}.category-tab:hover{transform:translateY(-1px)}.category-tab.is-active{border-color:var(--purple);background:var(--purple-soft);color:#5c4cc4}
.practice-layout{display:grid;grid-template-columns:minmax(290px,390px) minmax(0,1fr);gap:18px;align-items:start}.character-panel,.practice-card{background:var(--card);border:1px solid rgba(143,124,246,.12);border-radius:26px;box-shadow:var(--shadow)}
.character-panel{padding:20px;position:sticky;top:12px}.panel-heading{display:flex;align-items:flex-end;justify-content:space-between;gap:12px;margin-bottom:14px}.panel-heading h1{font-size:24px;margin:2px 0 0}.eyebrow{margin:0;color:var(--purple);font-size:12px;font-weight:900;letter-spacing:.12em}.progress-pill{background:#f5f2ff;color:#6b5bc6;padding:7px 10px;border-radius:999px;font-size:13px;font-weight:900;white-space:nowrap}.character-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:7px;max-height:610px;overflow:auto;padding:2px 3px 3px 1px}.character-button{aspect-ratio:1;border:1px solid #e8e5ef;background:#fff;border-radius:13px;font-size:22px;font-weight:900;cursor:pointer;position:relative}.character-button:hover{background:#faf8ff}.character-button.is-current{border:2px solid var(--purple);background:var(--purple-soft);color:#5a49c8}.character-button.is-done::after{content:"★";position:absolute;right:3px;top:1px;color:#e2b922;font-size:10px}
.practice-card{padding:20px 24px 24px}.practice-topline{display:grid;grid-template-columns:48px 1fr 48px;align-items:center;gap:12px}.round-button{width:48px;height:48px;border-radius:50%;border:1px solid var(--line);background:#fff;font-size:24px;font-weight:900;cursor:pointer}.current-character-wrap{text-align:center}.current-label{display:block;color:var(--muted);font-size:13px;font-weight:800}.current-character{display:block;font-size:50px;line-height:1.05;margin-top:2px}
.mode-switch{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;background:#f7f5fb;border-radius:16px;padding:6px;margin:14px auto 8px;max-width:560px}.mode-button{border:0;border-radius:12px;background:transparent;padding:10px 8px;font-weight:900;cursor:pointer}.mode-button.is-active{background:#fff;color:#5d4ed0;box-shadow:0 3px 10px rgba(84,71,127,.09)}.instruction{text-align:center;margin:10px 0 14px;color:#656879;font-weight:800}
.writing-board{position:relative;width:min(100%,580px);aspect-ratio:1;margin:0 auto;border:3px solid #d9d2fb;border-radius:28px;overflow:hidden;background:#fff;box-shadow:inset 0 0 0 8px #faf8ff}.board-grid{position:absolute;inset:0;background:linear-gradient(to right,transparent calc(50% - 1px),#ece9f5 calc(50% - 1px),#ece9f5 calc(50% + 1px),transparent calc(50% + 1px)),linear-gradient(to bottom,transparent calc(50% - 1px),#ece9f5 calc(50% - 1px),#ece9f5 calc(50% + 1px),transparent calc(50% + 1px));pointer-events:none}.guide-character{position:absolute;inset:0;display:grid;place-items:center;font-family:"Hiragino Kaku Gothic ProN","Yu Gothic","Meiryo",sans-serif;font-size:clamp(200px,42vw,390px);font-weight:700;line-height:1;color:rgba(123,111,181,.22);user-select:none;pointer-events:none;transition:opacity .18s,color .18s}.writing-board[data-mode="light"] .guide-character{color:rgba(123,111,181,.11)}.writing-board[data-mode="free"] .guide-character{opacity:0}.free-sample{display:none;position:absolute;top:13px;left:17px;width:78px;height:78px;border-radius:15px;background:#faf8ff;border:1px solid #e8e2ff;place-items:center;font-size:50px;font-weight:900;color:#7a6bd0;z-index:2;pointer-events:none}.writing-board[data-mode="free"] .free-sample{display:grid}.writing-board canvas{position:absolute;inset:0;width:100%;height:100%;touch-action:none;cursor:crosshair;z-index:3}
.encouragement{text-align:center;min-height:30px;margin:13px 0 8px;font-size:18px;font-weight:900;color:#6656c6}.practice-actions{display:grid;grid-template-columns:1fr 1fr 1.2fr;gap:9px;max-width:650px;margin:0 auto}.secondary-action,.primary-action{border:0;border-radius:15px;padding:13px 10px;font-weight:900;cursor:pointer}.secondary-action{background:#f5f3f8;color:#666273}.primary-action{background:linear-gradient(135deg,#8f7cf6,#a68ff8);color:#fff;box-shadow:0 7px 18px rgba(111,92,212,.24)}
.playground-footer{text-align:center;color:#77798a;font-size:13px;font-weight:700;padding:20px 8px 0}
@media(max-width:820px){.playground-shell{padding:14px 12px 26px}.playground-header{align-items:flex-start}.header-links{display:none}.brand-sub{margin-left:0}.category-tab{font-size:15px;padding:13px 8px}.practice-layout{grid-template-columns:1fr}.character-panel{position:static;padding:16px}.character-grid{grid-template-columns:repeat(8,1fr);max-height:none}.character-button{font-size:19px;border-radius:10px}.practice-card{padding:16px 12px 18px}.writing-board{width:min(100%,520px);border-radius:22px}.practice-actions{grid-template-columns:1fr 1fr}.primary-action{grid-column:1/-1}.current-character{font-size:44px}}
@media(max-width:520px){.brand-name{font-size:22px}.brand-mark{width:38px;height:38px}.category-tabs{gap:6px}.category-tab{font-size:13px;border-radius:14px}.character-grid{grid-template-columns:repeat(6,1fr);gap:6px}.character-panel{border-radius:20px}.character-button{font-size:18px}.practice-card{border-radius:20px}.practice-topline{grid-template-columns:42px 1fr 42px}.round-button{width:42px;height:42px}.mode-button{font-size:13px;padding:9px 3px}.instruction{font-size:14px}.free-sample{width:58px;height:58px;font-size:38px}.practice-actions{font-size:14px}.playground-footer{font-size:12px}}