:root,[data-theme="light"]{
  --bg:#F5F7F8; --surface:#FFFFFF; --fg:#191D21; --soft:#4A535C; --muted:#75808A; --line:#DDE5EA;
  --acc:#C97A3C; --btn-fg:#17130C; --halo:rgba(201,122,60,.16);
}
[data-theme="dark"]{
  --bg:#0F1214; --surface:#171B1E; --fg:#F1F2F0; --soft:#B8BEC4; --muted:#858D95; --line:rgba(255,255,255,.10);
  --acc:#D98A4A; --btn-fg:#15100B; --halo:rgba(217,138,74,.22);
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;min-height:100vh;background:
  radial-gradient(circle at 78% 10%,var(--halo),transparent 32%),
  linear-gradient(135deg,var(--bg),color-mix(in srgb,var(--bg) 88%,var(--surface)));
  color:var(--fg);font-family:Inter,system-ui,Arial,sans-serif;line-height:1.55;transition:background .3s,color .3s}
a{color:inherit;text-decoration:none}
.shell{min-height:100vh;display:grid;grid-template-rows:auto 1fr auto}
.top{height:76px;display:flex;align-items:center;justify-content:space-between;padding-inline:clamp(20px,5vw,64px)}
.brand{display:flex;align-items:center;gap:14px}
.logo{width:132px;height:auto}
.domain{font-family:"IBM Plex Mono",ui-monospace,monospace;font-size:.72rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted)}
.theme-switch{position:relative;display:inline-grid;grid-template-columns:1fr 1fr;align-items:center;width:104px;height:38px;
  border-radius:999px;background:color-mix(in srgb,var(--surface) 74%,transparent);border:1px solid var(--line);
  color:var(--fg);cursor:pointer;padding:3px}
.theme-option{position:relative;z-index:2;text-align:center;font-family:"IBM Plex Mono",ui-monospace,monospace;font-size:.62rem;
  letter-spacing:.04em;text-transform:uppercase;color:var(--muted)}
.theme-thumb{position:absolute;z-index:1;top:3px;left:3px;width:calc(50% - 3px);height:30px;border-radius:999px;
  background:var(--acc);box-shadow:0 8px 20px rgba(0,0,0,.16);transition:transform .22s cubic-bezier(.76,0,.24,1)}
[data-theme="light"] .theme-option:first-child,[data-theme="dark"] .theme-option:last-child{color:var(--btn-fg);font-weight:800}
[data-theme="dark"] .theme-thumb{transform:translateX(50px)}
.main{display:grid;place-items:center;padding:clamp(30px,6vw,72px) clamp(20px,5vw,64px)}
.login-card{width:min(100%,460px);background:color-mix(in srgb,var(--surface) 92%,transparent);border:1px solid var(--line);
  border-radius:10px;padding:clamp(28px,4vw,42px);box-shadow:0 26px 72px rgba(0,0,0,.12);backdrop-filter:blur(18px)}
.kicker{font-family:"IBM Plex Mono",ui-monospace,monospace;font-size:.72rem;letter-spacing:.16em;text-transform:uppercase;color:var(--acc);font-weight:700}
h1{font-family:Sora,Inter,system-ui,sans-serif;font-size:clamp(2rem,1.5rem + 2vw,3rem);line-height:1.05;margin:.85rem 0 0;letter-spacing:-.02em}
.lead{margin-top:1rem;color:var(--soft);font-size:1.02rem}
.google-btn{width:100%;height:58px;margin-top:2rem;display:flex;align-items:center;justify-content:center;gap:12px;
  border:1px solid var(--line);border-radius:8px;background:var(--fg);color:var(--bg);font-weight:800;font-size:1rem;cursor:pointer}
.google-mark{width:21px;height:21px;border-radius:50%;background:#fff;display:grid;place-items:center;color:#1A73E8;font-weight:900;font-family:Arial,sans-serif}
.small{margin-top:1rem;color:var(--muted);font-size:.88rem;text-align:center}
.divider{height:1px;background:var(--line);margin:1.5rem 0 1.1rem}
.secondary{display:flex;justify-content:center}
.collab-link{font-family:"IBM Plex Mono",ui-monospace,monospace;font-size:.72rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);
  padding:.7rem 1rem;border-radius:999px;border:1px solid transparent}
.collab-link:hover{color:var(--acc);border-color:color-mix(in srgb,var(--acc) 40%,transparent)}
.foot{padding:24px clamp(20px,5vw,64px);font-family:"IBM Plex Mono",ui-monospace,monospace;font-size:.7rem;letter-spacing:.04em;color:var(--muted);display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap}
@media (max-width:640px){
  .top{height:auto;padding-block:20px;align-items:flex-start}
  .brand{display:block}.domain{margin-top:6px}
  .login-card{padding:26px 22px}
}