*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}

body{
  font-family:'Inter',-apple-system,BlinkMacSystemFont,sans-serif;
  background:#08090f;
  color:#e2e8f0;
  min-height:100dvh;
  display:flex;
  justify-content:center;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}

/* --- ambient glow --- */
.glow{
  position:fixed;
  top:-180px;left:50%;
  width:600px;height:600px;
  transform:translateX(-50%);
  background:radial-gradient(circle,rgba(56,116,255,0.12) 0%,rgba(56,116,255,0) 70%);
  pointer-events:none;
  z-index:0;
}

/* --- layout --- */
main{
  position:relative;z-index:1;
  width:100%;max-width:400px;
  padding:64px 20px 48px;
  display:flex;flex-direction:column;align-items:center;
  text-align:center;
}

/* --- brand --- */
.mark{
  width:56px;height:56px;
  display:flex;align-items:center;justify-content:center;
  border-radius:16px;
  background:rgba(56,116,255,0.08);
  border:1px solid rgba(56,116,255,0.14);
  color:#5b8def;
  margin-bottom:20px;
}

h1{
  font-size:30px;font-weight:300;
  letter-spacing:-0.03em;
  color:#fff;
  margin-bottom:6px;
}
h1 span{font-weight:600}

.tagline{
  font-size:14px;color:#4b5e7e;
  margin-bottom:40px;
  letter-spacing:0.01em;
}

/* --- selector --- */
.selector{
  position:relative;
  display:grid;grid-template-columns:1fr 1fr 1fr;
  width:100%;
  background:rgba(255,255,255,0.04);
  border:1px solid rgba(255,255,255,0.06);
  border-radius:14px;
  padding:4px;
  margin-bottom:16px;
}

.sel-track{
  position:absolute;
  top:4px;left:4px;
  width:calc(33.333% - 2.67px);height:calc(100% - 8px);
  background:rgba(255,255,255,0.07);
  border-radius:11px;
  transition:transform .25s cubic-bezier(.4,0,.2,1);
  pointer-events:none;
  z-index:0;
}

.sel-track.pos-1{transform:translateX(100%)}
.sel-track.pos-2{transform:translateX(200%)}

.sel-opt{
  position:relative;z-index:1;
  background:none;border:none;
  padding:12px 8px 10px;
  cursor:pointer;
  display:flex;flex-direction:column;align-items:center;gap:2px;
  font-family:inherit;font-size:14px;font-weight:500;
  color:#64748b;
  transition:color .2s;
  border-radius:11px;
}

.sel-opt.active{color:#e2e8f0}

.sel-opt small{
  font-size:11px;font-weight:400;
  color:#3b4a63;
  font-family:'SF Mono','Consolas',monospace;
  letter-spacing:0.04em;
  display:flex;align-items:center;gap:6px;
  margin-top:1px;
}

/* --- status dot --- */
.dot{
  display:inline-block;
  width:6px;height:6px;
  border-radius:50%;
  background:#334155;
  vertical-align:middle;
  transition:background .3s;
}

.dot.ok{
  background:#34d399;
  box-shadow:0 0 6px rgba(52,211,153,0.5);
}

.dot.err{
  background:#f87171;
  box-shadow:0 0 6px rgba(248,113,113,0.4);
}

.dot.neutral{
  background:#94a3b8;
  box-shadow:0 0 4px rgba(148,163,184,0.3);
}

.dot.wait{
  animation:pulse 1.5s ease-in-out infinite;
}

@keyframes pulse{
  0%,100%{opacity:.4}
  50%{opacity:1}
}

/* --- install button --- */
.install{
  width:100%;
  padding:14px;
  border:none;border-radius:14px;
  font-family:inherit;font-size:15px;font-weight:600;
  color:#fff;cursor:pointer;
  display:flex;align-items:center;justify-content:center;gap:10px;
  letter-spacing:0.01em;

  background:linear-gradient(135deg,#3874ff 0%,#2558d6 100%);
  box-shadow:
    0 1px 0 rgba(255,255,255,0.08) inset,
    0 4px 20px rgba(56,116,255,0.25);
  transition:box-shadow .25s,transform .12s;
}

.install:hover{
  box-shadow:
    0 1px 0 rgba(255,255,255,0.08) inset,
    0 8px 32px rgba(56,116,255,0.35);
}

.install:active{transform:scale(.98)}

.install.outline{
  background:transparent;
  border:1px solid rgba(255,255,255,0.08);
  box-shadow:none;
  font-size:13px;
  font-weight:500;
  color:#475569;
  padding:12px;
}
.install.outline:hover{
  border-color:rgba(255,255,255,0.14);
  box-shadow:none;
  color:#64748b;
}

/* --- hidden --- */
.hidden{display:none !important}

/* --- post-download state --- */
#state-before,#state-after{width:100%}

.done-card{
  text-align:center;
  padding:32px 16px 28px;
}

.done-icon{
  width:52px;height:52px;
  margin:0 auto 16px;
  display:flex;align-items:center;justify-content:center;
  border-radius:50%;
  background:rgba(52,211,153,0.1);
  color:#34d399;
}

.done-title{
  font-size:18px;font-weight:600;color:#e2e8f0;
  margin-bottom:6px;
}

.done-sub{
  font-size:13px;color:#475569;
  line-height:1.5;
}

.next-steps{
  width:100%;
  background:rgba(255,255,255,0.03);
  border:1px solid rgba(255,255,255,0.06);
  border-radius:14px;
  padding:20px 22px;
  margin-bottom:32px;
  text-align:left;
}

.next-step{
  display:flex;align-items:flex-start;gap:14px;
  font-size:14px;color:#94a3b8;line-height:1.55;
}

.next-step+.next-step{margin-top:16px}

.next-step b{color:#e2e8f0;font-weight:600}

.ns-num{
  width:24px;height:24px;min-width:24px;
  display:inline-flex;align-items:center;justify-content:center;
  border-radius:50%;
  background:rgba(56,116,255,0.12);
  color:#5b8def;
  font-size:12px;font-weight:700;
  margin-top:1px;
}

/* --- responsive --- */
@media(max-width:440px){
  main{padding:48px 16px 40px}
  h1{font-size:26px}
}