:root {
  color-scheme: light;
  --blue: #246bfd;
  --blue-dark: #1553d8;
  --ink: #172033;
  --muted: #6e778a;
  --line: #e2e7f0;
  font-family: "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
}

* { box-sizing: border-box; }
body {
  margin: 0; min-height: 100vh; color: var(--ink);
  background:
    radial-gradient(circle at 15% 12%, rgba(36,107,253,.14), transparent 32%),
    radial-gradient(circle at 88% 88%, rgba(80,131,255,.12), transparent 34%),
    #f5f7fb;
}
button, input { font: inherit; }
.login-shell { min-height: 100vh; display: grid; place-items: center; padding: 28px 20px; }
.login-card {
  width: min(440px, 100%); padding: 38px; border: 1px solid rgba(224,229,239,.9); border-radius: 28px;
  background: rgba(255,255,255,.96); box-shadow: 0 22px 60px rgba(31,48,82,.12);
}
.brand-mark {
  display: grid; place-items: center; width: 54px; height: 54px; border-radius: 17px;
  color: #fff; background: linear-gradient(145deg, #3d7dff, #1553d8); box-shadow: 0 10px 22px rgba(36,107,253,.22);
  font-weight: 800; letter-spacing: -1px;
}
.eyebrow { margin: 25px 0 7px; color: var(--blue); font-size: 11px; font-weight: 800; letter-spacing: .13em; }
h1 { margin: 0; font-size: clamp(27px, 7vw, 34px); letter-spacing: -.04em; }
.intro { margin: 12px 0 27px; color: var(--muted); font-size: 14px; line-height: 1.7; }
form { display: grid; }
label { margin: 0 0 7px; color: #465064; font-size: 13px; font-weight: 700; }
input {
  width: 100%; height: 50px; padding: 0 14px; border: 1px solid var(--line); border-radius: 13px;
  color: var(--ink); background: #fafbfe; outline: none;
}
input:focus { border-color: var(--blue); box-shadow: 0 0 0 3px rgba(36,107,253,.11); background: #fff; }
#email { margin-bottom: 19px; }
.password-field { position: relative; }
.password-field input { padding-right: 66px; }
.password-field button {
  position: absolute; top: 6px; right: 6px; height: 38px; padding: 0 10px; border: 0; border-radius: 9px;
  color: var(--blue); background: transparent; font-size: 12px; font-weight: 700; cursor: pointer;
}
.error-message { min-height: 20px; margin: 9px 0 7px; color: #c53d4d; font-size: 12px; line-height: 1.6; }
.submit-button {
  height: 50px; border: 0; border-radius: 13px; color: #fff; background: var(--blue);
  box-shadow: 0 10px 22px rgba(36,107,253,.22); font-weight: 800; cursor: pointer;
}
.submit-button:hover { background: var(--blue-dark); }
.submit-button:disabled { opacity: .62; cursor: wait; }
.security-note { margin: 22px 0 0; color: var(--muted); font-size: 11px; text-align: center; }
.security-note span { color: #159568; font-weight: 900; }

@media (max-width: 520px) {
  .login-shell { align-items: start; padding: max(34px, env(safe-area-inset-top)) 14px 24px; }
  .login-card { padding: 29px 23px; border-radius: 24px; }
}