/*
  GuitarPT Stems — public stem-service site.
  Design goal: feels native to the GuitarPT iOS app. Single column,
  generous whitespace, accent colour is the App's primary (warm
  orange) so visitors making the App-jump experience visual
  continuity. No CSS framework — total weight ~6 KB gzipped, beats
  every iteration of "let's just import Tailwind".
*/

:root {
  --bg: #0e0f12;
  --bg-elev: #181a20;
  --bg-elev-2: #21242c;
  --border: rgba(255,255,255,.08);
  --text: #f0eee6;
  --text-mute: #9aa0aa;
  --accent: #ff8a3d;
  --accent-soft: rgba(255,138,61,.14);
  --accent-glow: rgba(255,138,61,.45);
  --error: #ff5d6c;
  --success: #8be9a3;
  --radius: 14px;
  --shadow: 0 4px 24px rgba(0,0,0,.32);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: radial-gradient(ellipse at top, #1a1d27 0%, #0a0b0e 70%);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text",
               "Helvetica Neue", system-ui, sans-serif;
  font-size: 17px;
  line-height: 1.55;
  min-height: 100vh;
}

a { color: var(--accent); }
a:hover { color: #ffae6f; }

main {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px 80px;
}

.site-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 22px 24px;
  border-bottom: 1px solid var(--border);
  max-width: 720px;
  margin: 0 auto 32px;
}
.brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
}
.brand__mark {
  font-size: 28px;
  color: var(--accent);
  text-shadow: 0 0 20px var(--accent-glow);
}
.brand__name { font-weight: 700; letter-spacing: -.02em; }
.brand__sub  { color: var(--text-mute); font-size: 14px; text-transform: uppercase; letter-spacing: .12em; }
.nav-link {
  text-decoration: none;
  color: var(--text-mute);
  font-size: 14px;
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  transition: all .15s;
}
.nav-link:hover { color: var(--text); border-color: rgba(255,255,255,.18); }

.hero h1 {
  font-size: clamp(32px, 5vw, 44px);
  letter-spacing: -.02em;
  margin: 0 0 14px;
  line-height: 1.1;
}
.lede {
  color: var(--text-mute);
  font-size: 18px;
  margin: 0 0 32px;
}
.lede strong { color: var(--text); font-weight: 600; }

/* ── Uploader ────────────────────────────────────────────────────── */

.uploader {
  background: var(--bg-elev);
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 36px 24px 18px;
  text-align: center;
  cursor: pointer;
  transition: all .18s;
}
.uploader:hover,
.uploader.is-dragover {
  border-color: var(--accent);
  background: var(--accent-soft);
  transform: translateY(-1px);
  box-shadow: var(--shadow);
}
.uploader__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}
.uploader__icon {
  font-size: 36px;
  width: 64px;
  height: 64px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--bg-elev-2);
  color: var(--accent);
  border: 1px solid var(--border);
}
.uploader__text strong {
  display: block;
  font-size: 18px;
  margin-bottom: 4px;
}
.uploader__text span {
  color: var(--text-mute);
  font-size: 14px;
}
.uploader__limits {
  display: flex;
  justify-content: center;
  gap: 18px;
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  color: var(--text-mute);
  font-size: 13px;
  flex-wrap: wrap;
}
.uploader__limits li::before {
  content: "·";
  margin-right: 10px;
  color: var(--accent);
}
.uploader__limits li:first-child::before { content: ""; margin-right: 0; }

/* ── Status ─────────────────────────────────────────────────────── */

.status {
  margin-top: 28px;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 24px;
}
.status__phase {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.status__phase::before {
  content: "";
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  animation: pulse 1.4s ease-in-out infinite;
  box-shadow: 0 0 10px var(--accent-glow);
}
.status__bar {
  height: 6px;
  background: var(--bg-elev-2);
  border-radius: 999px;
  overflow: hidden;
}
.status__bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), #ffb070);
  width: 0%;
  transition: width .3s ease-out;
}
.status__detail {
  margin-top: 10px;
  font-size: 13px;
  color: var(--text-mute);
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50%      { opacity: .35; transform: scale(.85); }
}

/* ── Result ─────────────────────────────────────────────────────── */

.result {
  margin-top: 28px;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
}
.result__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 18px;
  gap: 16px;
  flex-wrap: wrap;
}
.result__head h2 {
  margin: 0;
  font-size: 22px;
  letter-spacing: -.01em;
}
.result__key {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  background: var(--accent-soft);
  color: var(--accent);
  padding: 4px 12px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 600;
  border: 1px solid var(--accent);
}
.result__key small {
  color: var(--accent);
  opacity: .75;
  font-weight: 400;
}
.result__stems {
  display: grid;
  gap: 10px;
  margin-bottom: 22px;
}
.stem-row {
  background: var(--bg-elev-2);
  border-radius: 10px;
  padding: 12px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}
.stem-row__label {
  font-weight: 600;
  text-transform: capitalize;
}
.stem-row__size {
  color: var(--text-mute);
  font-size: 13px;
  font-variant-numeric: tabular-nums;
}
.result__note {
  color: var(--text-mute);
  font-size: 13px;
  margin: 12px 0 0;
}

/* ── Buttons ────────────────────────────────────────────────────── */

.btn {
  display: inline-block;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 15px;
  cursor: pointer;
  border: 1px solid transparent;
  text-decoration: none;
  transition: transform .12s, box-shadow .12s, background .12s;
  text-align: center;
}
.btn--primary {
  background: var(--accent);
  color: #1a1d27;
  width: 100%;
}
.btn--primary:hover {
  background: #ffae6f;
  transform: translateY(-1px);
  box-shadow: 0 6px 20px var(--accent-glow);
}
.btn--ghost {
  background: transparent;
  border-color: var(--border);
  color: var(--text);
}
.btn--ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* ── Errors ─────────────────────────────────────────────────────── */

.errorbox {
  margin-top: 28px;
  background: rgba(255,93,108,.08);
  border: 1px solid rgba(255,93,108,.4);
  border-radius: var(--radius);
  padding: 22px;
  color: var(--text);
}
.errorbox strong {
  display: block;
  color: var(--error);
  margin-bottom: 6px;
  font-size: 15px;
}
.errorbox p { margin: 0 0 14px; color: var(--text-mute); font-size: 14px; }

/* ── Sections after upload ──────────────────────────────────────── */

.cta, .howto, .privacy {
  margin-top: 64px;
  padding-top: 40px;
  border-top: 1px solid var(--border);
}
.cta h2, .howto h2, .privacy h2 {
  font-size: 22px;
  letter-spacing: -.01em;
  margin: 0 0 14px;
}
.cta p, .howto p, .privacy p {
  color: var(--text-mute);
  margin: 0 0 18px;
}
.howto ol {
  color: var(--text-mute);
  padding-left: 20px;
}
.howto li { margin-bottom: 10px; }
.howto li::marker { color: var(--accent); font-weight: 600; }

.cta .btn { width: auto; }

.site-foot {
  text-align: center;
  padding: 30px 24px 50px;
  color: var(--text-mute);
  font-size: 13px;
  border-top: 1px solid var(--border);
  max-width: 720px;
  margin: 60px auto 0;
}
.site-foot a { color: var(--text-mute); text-decoration: underline; text-decoration-color: var(--border); }
.site-foot a:hover { color: var(--accent); text-decoration-color: var(--accent); }

@media (max-width: 480px) {
  main { padding: 0 16px 60px; }
  .site-head { padding: 16px; }
  .uploader { padding: 28px 16px 14px; }
  .uploader__limits { gap: 12px; font-size: 12px; }
  .result { padding: 18px; }
}