:root {
  color-scheme: light dark;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --bg: #eef1f5;
  --panel: #ffffff;
  --text: #172033;
  --muted: #667085;
  --line: #d7dce5;
  --accent: #3157d5;
  --accent-hover: #2648ba;
  --danger: #b42318;
  --shadow: 0 24px 70px rgba(24, 35, 58, 0.14);
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #10141c; --panel: #1a202c; --text: #f2f4f7; --muted: #a8b0bf; --line: #384152; --accent: #7894f8; --accent-hover: #8da5ff; --danger: #ff8a80; --shadow: 0 28px 80px rgba(0, 0, 0, 0.38); }
}
* { box-sizing: border-box; }
body { margin: 0; min-width: 320px; min-height: 100vh; background: radial-gradient(circle at 15% 15%, rgba(74, 106, 224, 0.16), transparent 32rem), var(--bg); color: var(--text); }
.login-shell { min-height: 100vh; display: grid; place-items: center; padding: 24px; }
.login-card { width: min(100%, 420px); padding: 36px; border: 1px solid var(--line); border-radius: 18px; background: var(--panel); box-shadow: var(--shadow); }
.brand-mark { display: grid; place-items: center; width: 46px; height: 46px; border-radius: 13px; background: var(--accent); color: #fff; font-size: 22px; font-weight: 800; }
.eyebrow { margin: 24px 0 8px; color: var(--accent); font-size: 12px; font-weight: 750; letter-spacing: .09em; text-transform: uppercase; }
h1 { margin: 0; font-size: 27px; line-height: 1.25; }
.subtitle { margin: 10px 0 26px; color: var(--muted); font-size: 14px; }
label { display: block; margin: 16px 0 7px; font-size: 13px; font-weight: 700; }
input { width: 100%; height: 46px; border: 1px solid var(--line); border-radius: 10px; padding: 0 13px; background: var(--panel); color: var(--text); font: inherit; outline: none; }
input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(49, 87, 213, .18); }
.error { min-height: 20px; margin: 13px 0 0; color: var(--danger); font-size: 13px; }
button { width: 100%; height: 46px; margin-top: 7px; border: 0; border-radius: 10px; background: var(--accent); color: #fff; font: inherit; font-weight: 750; cursor: pointer; }
button:hover { background: var(--accent-hover); }
button:disabled { cursor: wait; opacity: .7; }
@media (max-width: 520px) { .login-shell { padding: 14px; } .login-card { padding: 28px 22px; } }