:root {
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #1b1b18;
  background: #f2f2ef;
  --yellow: #f5c742;
  --orange: #ff5226;
  --border: #d9d9d2;
  --muted: #6b6b64;
}

* { box-sizing: border-box; }

body {
  min-height: 100vh;
  margin: 0;
  display: grid;
  place-items: center;
  padding: 24px;
}

.sheet-app {
  width: min(620px, 100%);
  overflow: hidden;
  border: 1px solid var(--border);
  border-radius: 22px;
  background: #fff;
  box-shadow: 0 18px 55px rgba(25, 25, 20, .1);
}

.sheet-header {
  display: flex;
  align-items: center;
  gap: 13px;
  margin: 16px;
  padding: 12px 14px;
  border-radius: 16px;
  background: #f4f4f1;
}

.sheet-header img {
  width: 42px;
  height: 36px;
  object-fit: contain;
}

.sheet-header h1 {
  margin: 0;
  font-size: 27px;
  line-height: 1;
  letter-spacing: -.025em;
}

.update-button {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  width: auto;
  margin: 0 0 0 auto;
  padding: 10px 14px;
  border: 1px solid #d8d8d1;
  border-radius: 11px;
  background: #fff;
  color: #1b1b18;
  font: inherit;
  font-size: 14px;
  font-weight: 750;
  cursor: pointer;
}

.update-button span { font-size: 19px; line-height: 0; }
.update-button:hover { border-color: #ad8308; background: #fff9df; }
.update-button:disabled { opacity: .55; cursor: wait; }
.update-button.success { border-color: #54a966; color: #28753a; }
.update-button.error { border-color: #d86555; color: #b63527; }

.sheet-form { padding: 0 16px 16px; }

.drop-zone {
  display: grid;
  place-items: center;
  min-height: 290px;
  padding: 36px 24px;
  border: 2px dashed #bebeb5;
  border-radius: 18px;
  background: #fbfbf8;
  text-align: center;
  cursor: pointer;
  transition: border-color .15s, background .15s;
}

.drop-zone:hover,
.drop-zone.dragging {
  border-color: #ad8308;
  background: #fff9df;
}

.drop-zone input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

.xlsx {
  display: grid;
  place-items: center;
  width: 76px;
  height: 76px;
  margin-bottom: 22px;
  border-radius: 20px;
  background: var(--yellow);
  font-size: 14px;
  font-weight: 900;
}

.drop-zone strong {
  max-width: 100%;
  overflow-wrap: anywhere;
  font-size: 20px;
}

.drop-zone small {
  margin-top: 9px;
  color: var(--muted);
  font-size: 14px;
}

#submit {
  width: 100%;
  margin-top: 14px;
  padding: 17px 20px;
  border: 0;
  border-radius: 14px;
  background: #1b1b18;
  color: #fff;
  font: inherit;
  font-weight: 800;
  cursor: pointer;
}

#submit:disabled { opacity: .35; cursor: not-allowed; }

.result {
  display: none;
  margin: 13px 3px 0;
  color: var(--muted);
  font-size: 14px;
}

.result.visible { display: block; }
.result.error { color: #c23c2b; }

@media (max-width: 520px) {
  body { padding: 10px; }
  .sheet-header { margin: 10px; }
  .sheet-header h1 { font-size: 22px; }
  .update-button { padding: 9px 10px; font-size: 13px; }
  .sheet-form { padding: 0 10px 10px; }
  .drop-zone { min-height: 240px; }
}