:root{
  --bg:#0b1220; --panel:#111a2d; --panel-2:#152340;
  --brand:#4f46e5; --brand-2:#10b981; --accent:#ef4444;
  --text:#e6ecff; --muted:#8fa2c7; --border:#22314e;
}
*{box-sizing:border-box}
body{margin:0;font-family:-apple-system,"PingFang SC","Microsoft YaHei",Arial;background:var(--bg);color:var(--text)}
a{color:var(--brand-2);text-decoration:none}
button{cursor:pointer;font:inherit;color:var(--text);background:var(--brand);border:0;padding:8px 16px;border-radius:8px}
button.secondary{background:transparent;border:1px solid var(--border)}
button:disabled{opacity:.5;cursor:not-allowed}
input,textarea,select{width:100%;padding:10px 12px;border-radius:8px;border:1px solid var(--border);background:#0e1830;color:var(--text);font:inherit}
textarea{min-height:80px;resize:vertical}
.container{max-width:1200px;margin:0 auto;padding:20px}
.hero{padding:60px 20px;text-align:center;background:linear-gradient(135deg,#111a2d,#1a2c56)}
.hero h1{font-size:36px;margin:0 0 10px}
.hero p{color:var(--muted);margin:0}
.card{background:var(--panel);border:1px solid var(--border);border-radius:12px;padding:20px;margin-bottom:16px}
.grid{display:grid;gap:16px}
.grid.cols-2{grid-template-columns:1fr 1fr}
.grid.cols-3{grid-template-columns:repeat(3,1fr)}
@media(max-width:800px){.grid.cols-2,.grid.cols-3{grid-template-columns:1fr}}
.nav{display:flex;justify-content:space-between;align-items:center;padding:12px 20px;background:var(--panel);border-bottom:1px solid var(--border)}
.nav .brand{font-weight:700;letter-spacing:1px}
.nav .brand span{color:var(--brand-2)}
.tag{display:inline-block;padding:2px 8px;border-radius:20px;background:#1f2b4a;color:var(--muted);font-size:12px;margin-right:6px}
.tag.brand{background:rgba(79,70,229,.2);color:#a5b4fc}
.tag.ok{background:rgba(16,185,129,.2);color:#6ee7b7}
.tag.warn{background:rgba(239,68,68,.2);color:#fca5a5}

table{width:100%;border-collapse:collapse}
th,td{padding:10px;border-bottom:1px solid var(--border);text-align:left;font-size:14px}
th{color:var(--muted);font-weight:500}

.chat{display:flex;flex-direction:column;gap:12px;max-height:60vh;overflow-y:auto;padding:12px;background:#0a1327;border-radius:12px;border:1px solid var(--border)}
.msg{padding:10px 14px;border-radius:10px;max-width:90%}
.msg.tutor{background:#152340;border-left:3px solid var(--brand-2)}
.msg.me{background:#1a2547;align-self:flex-end;border-right:3px solid var(--brand)}
.msg small{color:var(--muted);font-size:11px;display:block;margin-bottom:4px}
.stream-cursor:after{content:'▌';color:var(--brand-2);animation:blink 1s infinite}
@keyframes blink{50%{opacity:0}}

.jxgbox{border-radius:12px;overflow:hidden;background:#fff}

.stat{display:flex;justify-content:space-between;align-items:center;padding:12px;background:var(--panel-2);border-radius:10px}
.stat .n{font-size:24px;font-weight:700;color:var(--brand-2)}

.radar{width:100%;max-width:340px}

.progress-strip{display:flex;gap:4px;flex-wrap:wrap}
.progress-strip .day{width:32px;height:32px;border-radius:6px;background:#1a2547;display:flex;align-items:center;justify-content:center;font-size:12px;color:var(--muted)}
.progress-strip .day.done{background:var(--brand-2);color:#fff}
.progress-strip .day.current{background:var(--brand);color:#fff;box-shadow:0 0 0 2px rgba(79,70,229,.4)}

.toast{position:fixed;bottom:20px;right:20px;background:var(--panel-2);border:1px solid var(--border);padding:12px 16px;border-radius:8px;z-index:99}
.toast.err{border-color:var(--accent)}