*{box-sizing:border-box}
:root{font-size:17px;font-family:system-ui,-apple-system,"Segoe UI",sans-serif;color:#18332d;background:#f0f6f3;color-scheme:light;--card:#fff;--border:#cbdad3;--muted:#526b61;--accent:#147a5a}
body{margin:0}
.auth-shell{min-height:100vh;min-height:100dvh;display:grid;place-items:center;padding:32px 20px}
.auth-card{width:min(480px,100%);background:var(--card);border:1px solid var(--border);border-radius:20px;padding:32px;box-shadow:0 12px 36px #123c2710}
h1{margin:0 0 12px;font-size:29px;line-height:1.2}
.muted{color:var(--muted);line-height:1.6;margin:0 0 24px}
form{display:grid;gap:16px}
label{display:grid;gap:7px;font-weight:600;font-size:15px}
input{width:100%;min-height:46px;border:1px solid var(--border);border-radius:9px;padding:10px 12px;font:inherit;font-size:17px;background:var(--card);color:inherit}
input:focus-visible{outline:3px solid #147a5a44;border-color:var(--accent)}
.btn{border:0;border-radius:9px;padding:13px 18px;min-height:46px;background:var(--accent);color:#fff;font:inherit;font-weight:650;cursor:pointer;margin-top:4px}
.btn:hover{filter:brightness(.93)}
a{color:var(--accent);text-underline-offset:3px}
.auth-links{display:flex;flex-wrap:wrap;gap:14px;margin:24px 0 0;font-size:15px}
.flash{border:1px solid #9bc9b2;background:#e9f7ef;border-radius:9px;padding:12px;margin-bottom:20px;line-height:1.5}
.flash.error{border-color:#e9abab;background:#fff0ef;color:#8d2521}
[data-theme="dark"]{color:#e5efe9;background:#13231e;color-scheme:dark;--card:#1d3028;--border:#40594c;--muted:#b3c8bd;--accent:#39a77e}
[data-theme="dark"] .flash{background:#244234;color:#e5efe9}[data-theme="dark"] .flash.error{background:#492b29;color:#ffd4d0}
@media(max-width:520px){.auth-shell{padding:20px 14px}.auth-card{padding:24px 20px}h1{font-size:26px}}

/* Compact account window, with paired registration fields on desktop. */
.auth-shell{padding:20px 16px}
.auth-card{width:min(567px,100%);padding:24px;border-radius:12px}
h1{font-size:24px;margin-bottom:8px}
.muted{font-size:15px;line-height:1.45;margin-bottom:18px}
form{gap:12px}
label{font-size:14px;gap:5px;min-width:0}
input{min-height:38px;padding:7px 10px;border-radius:6px}
.btn{min-height:38px;padding:9px 14px;border-radius:6px;font-size:15px}
.registration-form{grid-template-columns:repeat(2,minmax(0,1fr))}
.registration-form .btn{grid-column:1/-1}
.auth-links{margin-top:16px;gap:14px;font-size:14px}
.flash{padding:10px;margin-bottom:14px;font-size:15px}
@media(max-width:520px){.auth-card{padding:20px 18px}.registration-form{grid-template-columns:1fr}input{min-height:40px}h1{font-size:23px}}

.auth-card .btn{width:min(390px,100%);justify-self:center}