:root {
  --blue: #1687ff;
  --deep: #0f3f8c;
  --ink: #172033;
  --muted: #758195;
  --line: #e3ebf6;
  --panel: #ffffff;
  --page: #edf5ff;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  background:
    linear-gradient(135deg, rgba(22, 135, 255, .13), rgba(34, 201, 147, .08)),
    var(--page);
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  color: var(--ink);
}
.login-shell {
  width: min(980px, calc(100vw - 36px));
  min-height: 560px;
  display: grid;
  grid-template-columns: 1.1fr .9fr;
  background: var(--panel);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 20px 60px rgba(22, 63, 110, .16);
}
.brand-panel {
  padding: 58px 58px;
  background: linear-gradient(145deg, #1687ff, #0f63d8);
  color: white;
  position: relative;
}
.brand-mark {
  width: 54px;
  height: 54px;
  display: grid;
  place-items: center;
  border: 2px solid rgba(255, 255, 255, .6);
  transform: rotate(45deg);
  font-size: 24px;
  margin-bottom: 62px;
}
.brand-mark::first-letter { transform: rotate(-45deg); }
.brand-panel h1 {
  margin: 0 0 18px;
  font-size: 42px;
  letter-spacing: 0;
}
.brand-panel p {
  margin: 0;
  max-width: 420px;
  line-height: 1.9;
  color: rgba(255, 255, 255, .82);
}
.preview-lines {
  position: absolute;
  left: 58px;
  right: 58px;
  bottom: 62px;
  display: grid;
  gap: 14px;
}
.preview-lines span {
  height: 10px;
  border-radius: 999px;
  background: rgba(255, 255, 255, .24);
}
.preview-lines span:nth-child(2) { width: 72%; }
.preview-lines span:nth-child(3) { width: 46%; }
.login-card {
  padding: 74px 56px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.login-card h2 {
  margin: 0 0 10px;
  font-size: 30px;
}
.login-card p {
  margin: 0 0 32px;
  color: var(--muted);
}
form { display: grid; gap: 18px; }
label {
  display: grid;
  gap: 8px;
  color: #566274;
  font-size: 14px;
}
input {
  height: 46px;
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 0 13px;
  font: inherit;
  outline: none;
}
input:focus {
  border-color: var(--blue);
  box-shadow: 0 0 0 3px rgba(22, 135, 255, .12);
}
button {
  height: 46px;
  border: 0;
  border-radius: 4px;
  background: var(--blue);
  color: white;
  font: inherit;
  cursor: pointer;
}
.tip {
  margin-top: 22px;
  color: var(--muted);
  font-size: 13px;
}
@media (max-width: 760px) {
  .login-shell { grid-template-columns: 1fr; }
  .brand-panel { display: none; }
  .login-card { padding: 48px 24px; }
}