.checkout-summary{ border:1px solid var(--line); background:var(--surface); padding:16px 20px; margin-top:24px; }
.checkout-summary-row{ display:flex; justify-content:space-between; padding:6px 0; font-size:0.92rem; }
.checkout-summary-total{ border-top:1px solid var(--line); margin-top:8px; padding-top:12px; font-family:"IBM Plex Mono",monospace; font-weight:600; }

.checkout-form{ display:flex; flex-direction:column; gap:20px; margin-top:32px; max-width:480px; }
.checkout-form label{ display:flex; flex-direction:column; gap:6px; font-family:"IBM Plex Mono",monospace; font-size:0.72rem; text-transform:uppercase; letter-spacing:0.06em; color:var(--taupe); }
.checkout-form input, .checkout-form textarea{
  font-family:"Instrument Sans",sans-serif; font-size:1rem; color:var(--ink);
  border:none; border-bottom:1px solid var(--line); background:none; padding:8px 2px; outline:none;
  transition:border-color var(--m-instant) ease;
}
.checkout-form input:focus, .checkout-form textarea:focus{ border-color:var(--teal-deep); }
.field-error{ color:var(--magenta); font-size:0.78rem; text-transform:none; letter-spacing:0; }

.auth-tabs{ display:flex; gap:4px; margin-top:10px; border-bottom:1px solid var(--line); }
.auth-tab{
  font-family:"IBM Plex Mono",monospace; font-size:0.78rem; text-transform:uppercase; letter-spacing:0.04em;
  color:var(--taupe); text-decoration:none; padding:8px 4px; margin-bottom:-1px; border-bottom:2px solid transparent;
}
.auth-tab.is-active{ color:var(--ink); border-bottom-color:var(--teal-deep); }
.auth-tab:not(.is-active):hover{ color:var(--ink); }