:root { color-scheme: dark; font-family: Inter, ui-sans-serif, system-ui, -apple-system, sans-serif; background: #10131a; color: #eef1f7; }
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; background: radial-gradient(circle at top right, #202a40 0, #10131a 48%); }
.shell { width: min(680px, calc(100% - 32px)); margin: 0 auto; padding: 7vh 0 32px; }
.card { background: rgba(26, 31, 42, .92); border: 1px solid #30394c; border-radius: 18px; box-shadow: 0 20px 55px rgba(0,0,0,.25); padding: 28px; }
.hero { margin-bottom: 16px; }
.eyebrow { margin: 0 0 12px; color: #85a9ff; font-size: 12px; letter-spacing: .14em; font-weight: 700; }
h1 { margin: 0; font-size: clamp(30px, 6vw, 46px); letter-spacing: -.04em; }
.lead { margin: 14px 0 22px; color: #bbc4d5; line-height: 1.55; font-size: 17px; }
.rule { padding: 14px 16px; border-radius: 12px; background: #171c27; border: 1px solid #2d374b; }
.rule span { color: #85a9ff; font-size: 12px; text-transform: uppercase; letter-spacing: .1em; font-weight: 700; }
.rule p { margin: 7px 0 0; color: #eef1f7; }
.drop { min-height: 150px; border: 1px dashed #657696; border-radius: 14px; display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center; cursor: pointer; padding: 22px; transition: .2s ease; }
.drop:hover, .drop.drag { border-color: #85a9ff; background: #1b2435; }
.drop input { display: none; }
.drop-title { color: #eef1f7; font-size: 18px; font-weight: 700; }
.drop-subtitle { margin-top: 8px; color: #9aa8bf; font-size: 14px; max-width: 490px; overflow-wrap: anywhere; }
button, .download { margin-top: 16px; display: inline-flex; justify-content: center; align-items: center; min-height: 48px; border: 0; border-radius: 10px; font: inherit; font-weight: 700; text-decoration: none; cursor: pointer; }
.primary { width: 100%; background: #4d7cff; color: white; transition: transform .15s, opacity .15s; }
.primary:hover:not(:disabled) { transform: translateY(-1px); }
.primary:disabled { opacity: .45; cursor: not-allowed; }
.progress { margin-top: 22px; }
.progress-head { display: flex; justify-content: space-between; gap: 12px; color: #d9e2f5; font-size: 14px; }
.bar { height: 9px; margin-top: 10px; background: #101520; border-radius: 99px; overflow: hidden; }
.bar i { display: block; height: 100%; width: 0; background: linear-gradient(90deg, #4d7cff, #85a9ff); transition: width .25s ease; }
.muted, .footnote { color: #94a1b6; font-size: 13px; line-height: 1.45; }
.result { margin-top: 22px; padding: 16px; border-radius: 12px; background: #14271f; border: 1px solid #2f7051; }
.download { padding: 0 18px; background: #63d49a; color: #092014; }
.error { margin: 18px 0 0; color: #ff9c9c; line-height: 1.45; }
.hidden { display: none !important; }
.footnote { padding: 0 8px; }
@media (max-width: 520px) { .shell { width: min(100% - 20px, 680px); padding-top: 20px; } .card { padding: 20px; } }