:root {
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
  color: #172033;
  background: #eef3f8;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 18% 20%, rgba(73, 137, 255, .18), transparent 32%),
    radial-gradient(circle at 82% 78%, rgba(39, 170, 127, .15), transparent 30%),
    #eef3f8;
}

.login-shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 28px;
}

.login-card {
  width: min(440px, 100%);
  padding: 42px;
  border: 1px solid rgba(204, 216, 229, .9);
  border-radius: 18px;
  background: rgba(255, 255, 255, .96);
  box-shadow: 0 28px 75px rgba(34, 55, 84, .14);
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 52px;
  height: 52px;
  border-radius: 14px;
  color: #fff;
  background: linear-gradient(145deg, #347ef2, #205dc2);
  box-shadow: 0 10px 22px rgba(48, 121, 238, .28);
  font-weight: 800;
  letter-spacing: .04em;
}

.eyebrow {
  margin: 24px 0 7px;
  color: #377ee8;
  font-size: 11px;
  font-weight: 750;
  letter-spacing: .14em;
}

h1 { margin: 0; font-size: 28px; letter-spacing: -.02em; }
.subtitle { margin: 10px 0 28px; color: #718096; font-size: 14px; line-height: 1.7; }

form { display: grid; gap: 10px; }
label { margin-top: 7px; color: #405069; font-size: 13px; font-weight: 650; }

input {
  width: 100%;
  height: 46px;
  padding: 0 13px;
  border: 1px solid #d7e0e9;
  border-radius: 9px;
  outline: 0;
  color: #1f2b3e;
  background: #fbfdff;
  font-size: 15px;
  transition: border-color .16s, box-shadow .16s;
}

input:focus { border-color: #4b8df4; box-shadow: 0 0 0 3px rgba(75, 141, 244, .13); }
.password-field { position: relative; }
.password-field input { padding-right: 62px; }

.text-button {
  position: absolute;
  top: 7px;
  right: 7px;
  height: 32px;
  border: 0;
  color: #4b79b6;
  background: transparent;
  cursor: pointer;
}

.submit {
  height: 48px;
  margin-top: 12px;
  border: 0;
  border-radius: 9px;
  color: #fff;
  background: linear-gradient(135deg, #347ef2, #2165cf);
  box-shadow: 0 9px 20px rgba(52, 126, 242, .22);
  cursor: pointer;
  font-size: 15px;
  font-weight: 700;
}

.submit:disabled { cursor: wait; opacity: .7; }
.error { margin: 3px 0 0; color: #d4544b; font-size: 13px; }
.security-note { margin: 24px 0 0; color: #95a1b2; text-align: center; font-size: 12px; }

@media (max-width: 520px) {
  .login-shell { padding: 16px; }
  .login-card { padding: 30px 24px; border-radius: 14px; }
}