:root{--bg:#141b26;--panel:#1c2634;--line:#2c3a4f;--fg:#e8edf5;--muted:#8aa0b8;--acc:#5b8def;--acc2:#7a6fe6;--good:#3dce7a;--warn:#f0b34a}
*{box-sizing:border-box}
body{margin:0;font-family:system-ui,-apple-system,'Segoe UI',Roboto,sans-serif;background:var(--bg);color:var(--fg);min-height:100dvh;display:flex;flex-direction:column;letter-spacing:.01em}
header{padding:20px 20px 4px}
header h1{margin:0;font-size:1.7rem;background:linear-gradient(90deg,var(--acc),var(--acc2));-webkit-background-clip:text;background-clip:text;color:transparent}
.sub,.muted{color:var(--muted)}
nav{display:flex;gap:8px;padding:12px 18px;flex-wrap:wrap}
button{background:var(--acc);color:#fff;border:0;border-radius:10px;padding:11px 16px;font-size:.98rem;cursor:pointer;font-weight:600;transition:.15s}
button:hover{filter:brightness(1.1)}
button.ghost{background:transparent;border:1px solid var(--line);color:var(--fg)}
button:disabled{opacity:.4;cursor:not-allowed}
main{flex:1;padding:6px 18px 20px;max-width:640px;width:100%;margin:0 auto;display:flex;flex-direction:column}
main section[hidden]{display:none}
h2{font-size:1.2rem;margin:14px 0 6px}
.card{background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:14px;margin:10px 0;display:flex;justify-content:space-between;align-items:center;gap:12px}
.card strong{display:block;margin-bottom:2px}
.studyCard{background:var(--panel);border:1px solid var(--line);border-radius:18px;padding:22px;margin:14px 0;text-align:center}
.reverseToggle{display:block;text-align:right;font-size:.85rem;color:var(--acc2);margin-top:8px;cursor:pointer}
.face{font-size:1.55rem;font-weight:700;margin:18px 0}
.back{font-size:1.05rem;line-height:1.5;margin:10px 0;text-align:left;white-space:pre-wrap}
.hook{font-size:.92rem;color:var(--acc2);margin:6px 0;text-align:left;font-style:italic}
.grades{display:flex;gap:10px;justify-content:center;margin-top:12px}
.grades button{flex:1;max-width:120px}
.grades button[data-q="0"]{background:#d65a5a}
.grades button[data-q="3"]{background:var(--warn);color:#1a1a1a}
.grades button[data-q="5"]{background:var(--good)}
#studyReveal,#studyBackWrap{margin:6px 0}
.palaceStop{font-size:1.35rem;font-weight:700;background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:12px;text-align:center;margin:8px 0}
.palaceNav{display:flex;gap:10px;margin:12px 0;justify-content:space-between}
.palaceNav button{flex:1}
.palaceList{display:flex;flex-direction:column;gap:8px;margin-top:8px}
.palaceList button{text-align:left;background:transparent;border:1px solid var(--line);font-weight:500}
footer{padding:14px;text-align:center;font-size:.85rem;border-top:1px solid var(--line)}
#addDeck{margin-top:8px;width:100%}