Add multi-item sales

public/extras.css

@@ -7,4 +7,5 @@
 .auth-pending #appShell,.auth-required #appShell{display:none}.role-admin #authScreen,.role-readonly #authScreen{display:none}.auth-screen{min-height:100vh;display:grid;place-items:center;padding:24px;background:linear-gradient(145deg,#eef4ff,#f8fafc)}.auth-card{width:min(430px,100%);background:#fff;border:1px solid #dfe5ef;border-radius:18px;box-shadow:0 22px 60px #17203320;padding:34px}.auth-brand{margin-bottom:28px}.auth-card h1{margin:0 0 7px}.auth-card>div>p{color:#68758b}.auth-submit{width:100%;margin-top:14px}.auth-message{background:#fff0f0;color:#a51d1d;border:1px solid #fecaca;border-radius:8px;padding:10px 12px;margin:14px 0}.auth-logout{width:100%;margin-top:10px}.user-menu{display:flex;align-items:center;gap:10px;border-left:1px solid #e3e7ef;padding-left:18px}.user-menu span{display:grid;font-size:13px}.user-menu small{color:#758197}.admin-section{display:grid;gap:16px;border-bottom:1px solid #e3e7ef;padding-bottom:28px}.admin-section:last-child{border-bottom:0}.inline-user-form{display:grid;grid-template-columns:1fr 1fr 180px auto;gap:10px;align-items:end}.inline-user-form label{margin:0}.user-list,.audit-list{border:1px solid #e3e7ef;border-radius:10px;overflow:hidden}.user-list article{display:flex;justify-content:space-between;align-items:center;gap:15px;padding:14px;border-bottom:1px solid #edf0f5}.user-list article:last-child{border-bottom:0}.user-list small{display:block;color:#7b8799;margin-top:4px}.user-list article>div:last-child{display:flex;gap:7px;flex-wrap:wrap}.delete-backup{background:#fff0f0;color:#c62828}.audit-list{max-height:420px;overflow:auto}.audit-list article{display:grid;grid-template-columns:140px 180px 1fr;gap:12px;padding:10px 13px;border-bottom:1px solid #edf0f5;font-size:13px}.audit-list span{text-transform:capitalize}.audit-list small{color:#7b8799}@media(max-width:900px){.inline-user-form{grid-template-columns:1fr 1fr}.user-list article{align-items:flex-start;flex-direction:column}.audit-list article{grid-template-columns:1fr}.user-menu span{display:none}}@media(max-width:600px){.inline-user-form{grid-template-columns:1fr}.user-menu{padding-left:5px}.user-menu button{font-size:12px;padding:8px}.auth-card{padding:25px}}
 .inline-model-form{display:grid;grid-template-columns:minmax(220px,1fr) auto;gap:10px;align-items:end}.inline-model-form label{margin:0}.model-list{border:1px solid #e3e7ef;border-radius:10px;overflow:hidden}.model-list article{display:flex;justify-content:space-between;align-items:center;gap:15px;padding:14px;border-bottom:1px solid #edf0f5}.model-list article:last-child{border-bottom:0}.model-summary>div{display:flex;align-items:center;gap:9px}.model-summary small{display:block;color:#7b8799;margin-top:5px}.model-status{display:inline-flex;border-radius:99px;padding:3px 8px;font-size:11px;font-weight:750}.model-status.active{background:#dcfce7;color:#166534}.model-status.archived{background:#eef1f5;color:#526071}.model-actions{display:flex;gap:7px;flex-wrap:wrap}@media(max-width:760px){.inline-model-form{grid-template-columns:1fr}.model-list article{align-items:stretch;flex-direction:column}.model-actions{display:grid;grid-template-columns:repeat(2,minmax(0,1fr))}.model-actions button{text-align:center}}
 .conditional-fields{margin:2px 0 14px;padding:16px;border:1px solid #e3e7ef;border-radius:11px;background:#f8fafc}.conditional-fields h3{margin:0 0 12px}.conditional-hint{margin:4px 0 16px;padding:13px;border:1px dashed #d7deea;border-radius:9px;color:#68758b}.field-help{display:block;margin-top:-8px;color:#68758b}.warranty-pill{display:inline-flex;align-items:center;border-radius:99px;padding:5px 9px;font-size:12px;font-weight:750;white-space:nowrap}.warranty-pill.in-warranty{background:#dcfce7;color:#166534}.warranty-pill.expired{background:#fee2e2;color:#b91c1c}.warranty-pill.neutral{background:#eef1f5;color:#526071}.inline-warranty-form{display:grid;grid-template-columns:minmax(180px,1fr) 130px 150px auto;gap:10px;align-items:end}.inline-warranty-form label{margin:0}.warranty-list{border:1px solid #e3e7ef;border-radius:10px;overflow:hidden}.warranty-list article{display:flex;justify-content:space-between;align-items:center;gap:15px;padding:14px;border-bottom:1px solid #edf0f5}.warranty-list article:last-child{border-bottom:0}@media(max-width:760px){.inline-warranty-form{grid-template-columns:1fr}.warranty-list article{align-items:stretch;flex-direction:column}}
+.sale-items{margin:18px 0;padding:0;border:1px solid #d7deea;border-radius:11px;overflow:hidden}.sale-items legend{margin-left:12px;padding:0 6px;font-size:13px;font-weight:750}.sale-item-list{max-height:250px;overflow:auto}.sale-item{display:grid;grid-template-columns:auto minmax(0,1fr) 130px;align-items:center;gap:11px;margin:0;padding:11px 13px;border-bottom:1px solid #edf0f5}.sale-item>input{width:18px;height:18px}.sale-item small{display:block;margin-top:3px;color:#68758b}.sale-item-price{font-size:12px}.sale-item-price input{margin-top:4px;text-align:right}.sale-summary{display:flex;justify-content:space-between;align-items:center;padding:12px 14px;background:#f8fafc}.sale-summary span{color:#68758b}@media(max-width:520px){.sale-item{grid-template-columns:auto minmax(0,1fr)}.sale-item-price{grid-column:2}.sale-item-list{max-height:310px}}
 .filter-bar{display:flex;align-items:end;gap:9px;flex-wrap:wrap;padding:12px 16px;border-bottom:1px solid #e3e7ef}.filter-bar label{margin:0;min-width:125px;font-size:11px}.filter-bar select,.filter-bar input{padding:8px 9px;font-size:13px}.filter-bar .button,.filter-bar button{padding:9px 12px}.export-button{text-decoration:none}.customer-match{min-height:18px;margin:-7px 0 10px!important;color:#1d4ed8!important;font-size:12px}.diagnostic-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}.diagnostic-grid article{display:grid;gap:4px;padding:14px;border:1px solid #e3e7ef;border-radius:10px}.diagnostic-grid span,.diagnostic-grid small{color:#68758b}.diagnostic-grid strong{font-size:18px}.automatic-backups{display:grid;gap:12px;padding:16px;border:1px solid #e3e7ef;border-radius:10px}.automatic-backups h3,.automatic-backups p{margin:0}.backup-schedule{display:grid;grid-template-columns:minmax(190px,1.3fr) repeat(4,minmax(130px,1fr)) auto;gap:10px;align-items:end}.backup-schedule label{margin:0}.weekly-field[hidden]{display:none!important}.check-label{display:flex!important;align-items:center;gap:8px;min-height:42px}.check-label input{width:auto}.backup-schedule-status{display:flex;gap:18px;flex-wrap:wrap;font-size:13px}.export-links{display:flex;align-items:center;gap:8px;flex-wrap:wrap}.export-links .button{padding:8px 11px;text-decoration:none}@media(max-width:1100px){.backup-schedule{grid-template-columns:1fr 1fr 1fr}}@media(max-width:900px){.diagnostic-grid{grid-template-columns:1fr 1fr}.backup-schedule{grid-template-columns:1fr 1fr}}@media(max-width:600px){.filter-bar{align-items:stretch}.filter-bar label,.filter-bar .button,.filter-bar button{width:100%}.diagnostic-grid,.backup-schedule{grid-template-columns:1fr}}