:root {
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #17212b;
  background: #f4f6f8;
  --accent: #0f766e;
  --accent-dark: #115e59;
  --border: #d9e0e7;
  --muted: #667085;
  --surface: #ffffff;
  --danger: #b42318;
  --success: #067647;
}
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; background: #f4f6f8; }
button, input { font: inherit; }
.shell { width: min(760px, calc(100% - 28px)); margin: 0 auto; padding: 30px 0 50px; }
.header { margin-bottom: 20px; }
.back { display: inline-block; margin-bottom: 20px; color: var(--accent); text-decoration: none; font-weight: 650; }
.title-row { display: flex; align-items: center; gap: 14px; }
.mark { width: 50px; height: 50px; display: grid; place-items: center; border-radius: 15px; background: var(--accent); color: white; font-size: 1.6rem; font-weight: 800; }
h1 { margin: 0 0 4px; font-size: clamp(1.55rem, 4vw, 2rem); }
p { margin: 0; }
.header p, .safety p { color: var(--muted); line-height: 1.5; }
.panel { padding: 26px; border: 1px solid var(--border); border-radius: 18px; background: var(--surface); box-shadow: 0 14px 38px rgba(15, 23, 42, .08); }
.drop-zone { min-height: 220px; padding: 28px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 8px; border: 2px dashed #a9b7c5; border-radius: 16px; background: #f8fafc; text-align: center; cursor: pointer; transition: .15s ease; }
.drop-zone:hover, .drop-zone:focus, .drop-zone.dragging { border-color: var(--accent); background: #f0fdfa; outline: none; }
.drop-zone span:last-child { color: var(--muted); }
.drop-icon { width: 48px; height: 48px; border-radius: 50%; display: grid; place-items: center; background: #dff7f3; color: var(--accent-dark); font-size: 1.8rem; }
.file-card { margin-top: 14px; padding: 13px 15px; display: flex; align-items: center; justify-content: space-between; gap: 15px; border: 1px solid var(--border); border-radius: 12px; }
.file-card strong, .file-card span { display: block; }
.file-card span { margin-top: 3px; color: var(--muted); font-size: .88rem; }
.link-button { border: 0; background: none; color: var(--accent); font-weight: 700; cursor: pointer; }
.credential-row { margin-top: 20px; }
.credential-row label { display: block; margin-bottom: 7px; font-weight: 700; }
.credential-row small { display: block; margin-top: 6px; color: var(--muted); }
.credential-input { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 8px; }
input { min-height: 48px; width: 100%; padding: 0 13px; border: 1px solid var(--border); border-radius: 10px; }
input:focus, button:focus-visible { outline: 3px solid rgba(15, 118, 110, .2); outline-offset: 1px; border-color: var(--accent); }
.primary-button, .secondary-button { min-height: 48px; border-radius: 10px; font-weight: 750; cursor: pointer; }
.primary-button { width: 100%; margin-top: 22px; padding: 0 20px; border: 1px solid var(--accent); background: var(--accent); color: white; }
.primary-button:hover:not(:disabled) { background: var(--accent-dark); }
.primary-button:disabled { opacity: .45; cursor: not-allowed; }
.secondary-button { padding: 0 16px; border: 1px solid var(--border); background: #f8fafc; color: #344054; }
.progress-area { margin-top: 24px; padding-top: 20px; border-top: 1px solid var(--border); }
.progress-line { display: flex; justify-content: space-between; gap: 14px; }
.progress-track { height: 10px; margin-top: 10px; overflow: hidden; border-radius: 999px; background: #e7ecef; }
.progress-bar { width: 0; height: 100%; border-radius: inherit; background: var(--accent); transition: width .2s ease; }
#progress-detail { margin-top: 8px; color: var(--muted); font-size: .9rem; }
.message { margin-top: 18px; padding: 14px 16px; border-radius: 11px; line-height: 1.45; }
.message.success { background: #ecfdf3; color: var(--success); }
.message.error { background: #fef3f2; color: var(--danger); }
.safety { margin-top: 16px; padding: 16px 18px; border: 1px solid var(--border); border-radius: 14px; background: rgba(255,255,255,.65); }
.safety strong { display: block; margin-bottom: 5px; }
[hidden] { display: none !important; }
@media (max-width: 560px) {
  .shell { padding-top: 18px; }
  .panel { padding: 18px; }
  .drop-zone { min-height: 190px; padding: 20px; }
  .credential-input { grid-template-columns: 1fr; }
}