:root{--font-sans:'Inter',-apple-system,sans-serif;--font-mono:'JetBrains Mono',monospace;--radius:12px;--transition:0.2s ease}
[data-theme="dark"]{--bg:#0F0F1A;--bg-card:rgba(26,26,46,0.95);--bg-input:rgba(16,185,129,0.05);--border:rgba(16,185,129,0.12);--text:#E8E4F0;--text2:#80B0A0;--text3:#507060;--primary:#10B981;--accent:#F59E0B;--gradient:linear-gradient(135deg,#10B981,#059669)}
*{margin:0;padding:0;box-sizing:border-box}body{font-family:var(--font-sans);background:var(--bg);color:var(--text);min-height:100vh}
.app{max-width:700px;margin:0 auto}.header{padding:16px 24px;border-bottom:1px solid var(--border);display:flex;justify-content:space-between;align-items:center}
.header h1{font-size:1rem;font-weight:700;background:var(--gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.btn{font-family:var(--font-sans);font-size:.8rem;font-weight:500;padding:8px 14px;border-radius:8px;border:none;cursor:pointer;transition:all var(--transition)}
.btn-primary{background:var(--gradient);color:#fff}.btn-primary:hover{transform:translateY(-1px)}
.btn-ghost{background:transparent;color:var(--text2)}.btn-ghost:hover{background:var(--bg-input)}
.btn-sm{font-size:.75rem;padding:6px 10px}
.main{padding:20px;display:flex;flex-direction:column;gap:16px}
.habit-card{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius);padding:16px;animation:fadeIn .3s}
.habit-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:10px}
.habit-name{font-size:.9rem;font-weight:600}
.habit-streak{font-family:var(--font-mono);font-size:.82rem;color:var(--accent);font-weight:600}
.habit-heatmap{display:grid;grid-template-columns:repeat(7,1fr);gap:3px;margin-bottom:10px}
.heat{aspect-ratio:1;border-radius:3px;background:var(--bg-input);transition:background var(--transition);cursor:pointer}
.heat.done{background:var(--primary)}.heat.today{outline:2px solid var(--accent);outline-offset:-1px}
.habit-stats{font-size:.72rem;color:var(--text3);display:flex;gap:12px}
.habit-actions{display:flex;gap:6px;margin-top:8px}
@keyframes fadeIn{from{opacity:0;transform:translateY(-4px)}to{opacity:1;transform:translateY(0)}}