.btn-primary,.btn-secondary,.btn-ghost,.btn-quiet{min-height:40px;display:inline-flex;align-items:center;justify-content:center;gap:6px;padding:10px 24px;border-radius:var(--r-3);font-family:var(--font-ui);font-size:var(--t-body);font-weight:600;line-height:1;text-decoration:none;cursor:pointer;transition:transform var(--d-fast) var(--ease-out),box-shadow var(--d-fast) var(--ease-out),background var(--d-base) var(--ease-out),border-color var(--d-base) var(--ease-out),color var(--d-base) var(--ease-out)}.btn-primary{background:var(--primary);color:var(--me-bach);border:none;box-shadow:0 4px 0 var(--chau-hong-2)}.btn-primary:hover{transform:translateY(-1px)}.btn-primary:active{transform:translateY(2px);box-shadow:0 2px 0 var(--chau-hong-2)}.btn-secondary{background:transparent;color:var(--primary);border:1.5px solid var(--primary)}.btn-secondary:hover{background:var(--primary-soft)}.btn-secondary:active{transform:translateY(1px)}.btn-ghost{background:transparent;color:var(--primary);border:1px solid transparent;padding-inline:8px}.btn-ghost:hover{text-decoration:underline;text-underline-offset:3px}.btn-ghost:active{transform:translateY(1px)}.btn-quiet{background:var(--surface2);color:var(--text2);border:1px solid transparent}.btn-quiet:hover{color:var(--text);background:var(--hover)}.btn-quiet:active{transform:translateY(1px)}.btn-primary:focus-visible,.btn-secondary:focus-visible,.btn-ghost:focus-visible,.btn-quiet:focus-visible,.quick-add:focus-visible{outline:2px solid var(--primary);outline-offset:2px}.btn-primary:disabled,.btn-secondary:disabled,.btn-ghost:disabled,.btn-quiet:disabled,.btn-primary[disabled],.btn-secondary[disabled],.btn-ghost[disabled],.btn-quiet[disabled]{opacity:.55;cursor:not-allowed;transform:none;box-shadow:none}.btn-lg{min-height:48px;padding:12px 28px;font-size:var(--t-body-lg)}.btn-sm{min-height:32px;padding:7px 16px;font-size:var(--t-small)}.w-full{width:100%;margin-top:16px}.quick-add{width:32px;height:32px;border-radius:var(--r-2);border:1px solid var(--border);background:var(--surface2);color:var(--primary);font-size:20px;cursor:pointer;display:flex;align-items:center;justify-content:center;flex-shrink:0;transition:background var(--d-base) var(--ease-out),color var(--d-base) var(--ease-out),border-color var(--d-base) var(--ease-out),transform var(--d-fast) var(--ease-out);line-height:1}.quick-add:hover{background:var(--primary);color:var(--me-bach);border-color:transparent;transform:scale(1.1)}.quick-add.added{background:var(--status-mastered-bg);color:var(--status-mastered);border-color:var(--status-mastered);font-size:14px}