:root {
  --g: #17684a;
  --ink: #17231e;
  --muted: #748079;
  --line: #dfe7e2;
}
* {
  box-sizing: border-box;
}
body {
  margin: 0;
  background: #f5f8f6;
  color: var(--ink);
  font-family: Arial, 'Microsoft YaHei';
}
main {
  max-width: 1120px;
  margin: auto;
  padding: 35px 20px;
}
.auth-card {
  max-width: 820px;
  margin: 8vh auto;
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 40px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 40px;
}
.auth-card small,
header small {
  color: var(--g);
  letter-spacing: 2px;
}
.auth-card p {
  color: var(--muted);
  line-height: 1.7;
}
.auth-card form,
form {
  display: grid;
  gap: 12px;
}
.tabs {
  display: grid;
  grid-template-columns: 1fr 1fr;
}
.tabs button {
  background: #edf3ef;
  color: var(--muted);
}
.tabs button.on {
  background: var(--g);
  color: #fff;
}
input,
select,
textarea,
button {
  padding: 11px;
  border-radius: 8px;
  border: 1px solid var(--line);
  font: inherit;
}
button {
  border: 0;
  background: var(--g);
  color: #fff;
  cursor: pointer;
}
header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.status-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin: 25px 0;
}
.status-grid article,
.workspace > form,
.workspace > div {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 13px;
  padding: 20px;
  color: var(--muted);
}
.status-grid b {
  display: block;
  color: var(--ink);
  font-size: 20px;
  margin-top: 9px;
}
.workspace {
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: 18px;
}
.workspace label {
  display: grid;
  gap: 5px;
  color: var(--ink);
  font-size: 13px;
}
.outline {
  background: #fff;
  color: var(--g);
  border: 1px solid var(--g);
}
.teacher-course {
  display: flex;
  justify-content: space-between;
  padding: 13px 0;
  border-bottom: 1px solid var(--line);
}
.teacher-course h3 {
  margin: 0;
  font-size: 15px;
}
.teacher-course small {
  color: var(--muted);
}
#teacherMessage {
  color: #17684a;
}
@media (max-width: 750px) {
  .auth-card,
  .workspace {
    grid-template-columns: 1fr;
  }
  .status-grid {
    grid-template-columns: 1fr;
  }
  header {
    align-items: start;
  }
}