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.35rem;font-size:.7rem;font-weight:600;transition:all .15s}.lesson-tag-btn:hover{color:#fff;border-color:var(--accent-indigo);background:#6366f14d}.mastered-btn{border:1px solid var(--border-color);color:var(--text-muted);cursor:pointer;background:#ffffff0f;border-radius:6px;padding:.2rem .55rem;font-size:.75rem;font-weight:700;transition:all .2s}.mastered-btn.active{color:#34d399;background:#10b98140;border-color:#10b98199}.pattern-card{background:var(--bg-card);-webkit-backdrop-filter:blur(16px);backdrop-filter:blur(16px);border:1px solid var(--border-color);border-radius:var(--radius-md);margin-bottom:1.2rem;padding:1.25rem}.pattern-card h3{font-family:var(--font-heading);color:#f1f5f9;margin-bottom:.9rem;font-size:1.05rem;font-weight:700}.pattern-grid{grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:.8rem;display:grid}.pattern-item{border:1px solid var(--border-color);border-radius:var(--radius-sm);background:#0f172a99;padding:.8rem}.pattern-en{color:var(--accent-indigo);font-size:.9rem;font-weight:700}.pattern-vi{color:var(--text-muted);margin-top:.2rem;font-size:.8rem}.hidden{display:none!important}.toast-notification{color:#fff;border:1px solid var(--accent-indigo);border-radius:var(--radius-sm);z-index:1000;background:#1e293b;padding:.75rem 1.25rem;font-size:.9rem;font-weight:500;position:fixed;bottom:2rem;right:2rem;box-shadow:0 10px 25px #00000080}