:root {
  --bg: #f9f9ff;
  --surface: #ffffff;
  --surface-variant: #e4e2ec;
  --primary: #3f568f;
  --on-primary: #ffffff;
  --primary-container: #dbe1ff;
  --on-primary-container: #001a41;
  --ink: #1a1b20;
  --muted: #5b5e68;
  --line: #c8c5d0;
  --bad: #ba1a1a;
  --good: #146c37;
}

:root[data-theme="dark"] {
  --bg: #000000;
  --surface: #0b0b0b;
  --surface-variant: #202020;
  --primary: #ffffff;
  --on-primary: #000000;
  --primary-container: #2a2a2a;
  --on-primary-container: #ffffff;
  --ink: #ffffff;
  --muted: #b5b5b5;
  --line: #565656;
  --bad: #ffffff;
  --good: #ffffff;
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 16px/1.45 ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif; }
a { color: inherit; }
.top, main, .foot { max-width: 76rem; margin: 0 auto; }

.top { min-height: 5.25rem; display: flex; align-items: center; justify-content: space-between; padding: 0 1.5rem; }
.brand { display: flex; align-items: center; gap: .65rem; font-size: 1.12rem; font-weight: 750; text-decoration: none; }
.mark { width: 25px; height: 25px; fill: none; stroke: var(--primary); stroke-width: 1.8; stroke-linejoin: round; stroke-linecap: round; }
.mark .arrow { stroke: var(--primary); }.mark .fold { opacity: .45; }

.theme-switch { display: flex; align-items: center; gap: .7rem; color: var(--muted); font-size: .78rem; font-weight: 650; letter-spacing: .04em; text-transform: uppercase; cursor: pointer; }
.theme-switch input { appearance: none; width: 3rem; height: 2rem; margin: 0; padding: .25rem; border: 0; border-radius: 1rem; background: var(--surface-variant); cursor: pointer; }
.theme-switch input::after { content: ""; display: block; width: 1.5rem; height: 1.5rem; border-radius: 50%; background: var(--muted); transition: transform .18s, background .18s; }
.theme-switch input:checked { background: var(--primary); }.theme-switch input:checked::after { transform: translateX(1rem); background: var(--on-primary); }

main { padding: 1.25rem 1.5rem 4rem; }
.box { overflow: hidden; border: 1px solid var(--line); border-radius: 8px; background: var(--surface); box-shadow: 0 2px 6px #00000014; }
.workflow-label { padding: 1rem 1.25rem; background: var(--primary-container); color: var(--on-primary-container); font-size: .82rem; font-weight: 700; letter-spacing: .05em; text-transform: uppercase; }
.converter-grid { display: grid; grid-template-columns: 1.15fr 1.6fr .62fr; }
.step { min-height: 16rem; padding: 1.25rem; }.step + .step { border-left: 1px solid var(--line); }
.step-num, .format-label { font-size: .75rem; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; }.step-num { display: block; color: var(--muted); }

.drop { display: flex; flex-direction: column; align-items: flex-start; gap: 1rem; cursor: pointer; transition: background .18s; }.drop.over { background: var(--primary-container); color: var(--on-primary-container); }.drop.has { background: var(--surface-variant); }
.drop-title { max-width: 17rem; margin: auto 0 0; font-size: clamp(1.3rem, 2vw, 1.75rem); font-weight: 700; line-height: 1.15; overflow-wrap: anywhere; }.drop-sub { max-width: 18rem; margin: .45rem 0 0; color: var(--muted); font-size: .9rem; }

.format-step { display: flex; flex-direction: column; }.format-label { margin-top: 1.5rem; color: var(--muted); }.format-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: .5rem; margin-top: .85rem; overflow: auto; max-height: 10.5rem; padding-right: .2rem; }
.format-option { min-height: 2.5rem; border: 1px solid var(--line); border-radius: 8px; background: var(--surface); color: var(--ink); font: 650 .82rem/1 ui-sans-serif, system-ui, sans-serif; cursor: pointer; transition: background .15s, border-color .15s, color .15s; }.format-option:hover { border-color: var(--primary); background: var(--primary-container); color: var(--on-primary-container); }.format-option.selected { border-color: var(--primary); background: var(--primary); color: var(--on-primary); }

.action-step { display: flex; flex-direction: column; justify-content: space-between; background: var(--surface-variant); }.btn { border: 0; border-radius: 8px; padding: .8rem 1rem; background: transparent; color: var(--primary); font: 700 .92rem/1.2 ui-sans-serif, system-ui, sans-serif; cursor: pointer; transition: background .15s, color .15s; }.btn:disabled { cursor: not-allowed; opacity: .45; }.btn:not(:disabled):hover { background: var(--primary-container); color: var(--on-primary-container); }.primary { min-height: 5rem; background: var(--primary); color: var(--on-primary); }.primary:not(:disabled):hover { background: var(--ink); color: var(--bg); }
:is(.btn, .format-option, .theme-switch input):focus-visible { outline: 3px solid var(--primary); outline-offset: 2px; }

.status { min-height: 3rem; margin: 0; padding: .85rem 1.25rem; border-top: 1px solid var(--line); color: var(--muted); font-size: .9rem; }.status.ok { color: var(--good); }.status.bad { color: var(--bad); }.status.busy { color: var(--ink); }.service-note { margin: 1rem 0 0; color: var(--muted); font-size: .8rem; letter-spacing: .04em; }
.foot { padding: 1.4rem 1.5rem; color: var(--muted); font-size: .85rem; }.foot p { margin: 0; }

@media (max-width: 52rem) { .converter-grid { grid-template-columns: 1fr 1.35fr; }.action-step { grid-column: 1 / -1; min-height: 7rem; border-top: 1px solid var(--line); border-left: 0 !important; } }
@media (max-width: 44rem) { .top, main, .foot { padding-left: 1rem; padding-right: 1rem; }.top { min-height: 4.5rem; }.theme-switch span { display: none; } main { padding-top: .75rem; }.converter-grid { grid-template-columns: 1fr; }.step { min-height: 11.5rem; }.step + .step { border-top: 1px solid var(--line); border-left: 0; }.action-step { min-height: 7rem; }.primary { min-height: 3.5rem; } }
@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }