*, *::before, *::after { box-sizing: border-box; }
body {
  margin: 0; font-family: "Noto Sans KR", sans-serif;
  background: #fffbf5; color: #0f172a; min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  padding: 24px 0;
}
body::before {
  content: ""; position: fixed; inset: 0; z-index: 0; pointer-events: none;
  background:
    radial-gradient(ellipse 70% 55% at 5% 0%, rgba(37,99,235,0.08) 0%, transparent 55%),
    radial-gradient(ellipse 55% 45% at 95% 0%, rgba(124,58,237,0.06) 0%, transparent 50%);
}

.auth-container {
  position: relative; z-index: 1;
  width: min(440px, calc(100% - 40px));
  padding: 48px 36px 40px;
  background: rgba(255,255,255,0.85);
  border: 1px solid rgba(200,215,255,0.6);
  border-radius: 24px;
  backdrop-filter: blur(24px);
  box-shadow: 0 8px 40px rgba(99,120,220,0.1);
}

.auth-logo {
  display: flex; align-items: center; gap: 12px;
  justify-content: center; margin-bottom: 32px; text-decoration: none;
}
.auth-logo-icon {
  width: 44px; height: 44px; border-radius: 14px;
  background: linear-gradient(135deg, #2563eb, #7c3aed);
  display: flex; align-items: center; justify-content: center;
  font-weight: 900; font-size: 1.2rem; color: #fff;
  box-shadow: 0 4px 14px rgba(37,99,235,0.3);
}
.auth-logo-text strong { display: block; font-size: 1.1rem; font-weight: 800; color: #1e293b; }
.auth-logo-text small { display: block; font-size: 0.75rem; color: #94a3b8; }

.auth-title {
  text-align: center; font-size: 1.5rem; font-weight: 800;
  color: #1e293b; margin: 0 0 8px;
}
.auth-subtitle {
  text-align: center; font-size: 0.88rem; color: #94a3b8;
  margin: 0 0 28px;
}

.form-group { margin-bottom: 18px; }
.form-label {
  display: block; font-size: 0.82rem; font-weight: 700;
  color: #475569; margin-bottom: 6px;
}
.form-input {
  width: 100%; padding: 13px 16px; border-radius: 12px;
  border: 1.5px solid rgba(200,215,255,0.8);
  background: rgba(248,250,255,0.8);
  font-size: 0.92rem; font-family: inherit; color: #1e293b;
  transition: border-color 200ms, box-shadow 200ms;
  outline: none;
}
.form-input:focus {
  border-color: #2563eb;
  box-shadow: 0 0 0 3px rgba(37,99,235,0.1);
}
.form-input::placeholder { color: #cbd5e1; }

.form-row { display: flex; gap: 12px; }
.form-row .form-group { flex: 1; }

.password-hint {
  font-size: 0.76rem; color: #94a3b8; margin-top: 4px;
}

.btn-submit {
  width: 100%; padding: 14px; border: none; border-radius: 14px;
  background: linear-gradient(135deg, #2563eb, #7c3aed);
  color: #fff; font-size: 1rem; font-weight: 700;
  font-family: inherit; cursor: pointer; margin-top: 8px;
  box-shadow: 0 4px 16px rgba(37,99,235,0.3);
  transition: transform 120ms, box-shadow 120ms;
}
.btn-submit:hover { transform: translateY(-1px); box-shadow: 0 6px 20px rgba(37,99,235,0.4); }
.btn-submit:active { transform: translateY(0); }
.btn-submit:disabled { opacity: 0.6; cursor: not-allowed; transform: none; }

.auth-footer {
  text-align: center; margin-top: 24px;
  font-size: 0.84rem; color: #94a3b8;
}
.auth-footer a { color: #2563eb; text-decoration: none; font-weight: 600; }
.auth-footer a:hover { text-decoration: underline; }

.msg {
  padding: 10px 14px; border-radius: 10px; font-size: 0.84rem;
  margin-bottom: 16px; display: none;
}
.msg.error { display: block; background: #fef2f2; color: #dc2626; border: 1px solid #fecaca; }
.msg.success { display: block; background: #f0fdf4; color: #16a34a; border: 1px solid #bbf7d0; }

.back-link {
  display: block; text-align: center; margin-top: 16px;
  font-size: 0.82rem; color: #94a3b8; text-decoration: none;
}
.back-link:hover { color: #2563eb; }

.grade-info {
  background: rgba(248,250,255,0.9);
  border: 1px solid rgba(200,215,255,0.5);
  border-radius: 14px; padding: 16px 18px;
  margin-bottom: 24px;
}
.grade-info-title {
  font-size: 0.8rem; font-weight: 700; color: #475569;
  margin: 0 0 10px;
}
.grade-list { list-style: none; padding: 0; margin: 0; }
.grade-list li {
  font-size: 0.78rem; color: #64748b; padding: 3px 0;
  display: flex; align-items: center; gap: 8px;
}
.grade-badge {
  display: inline-block; padding: 2px 8px; border-radius: 6px;
  font-size: 0.72rem; font-weight: 700;
}
.grade-badge.associate { background: #e0f2fe; color: #0284c7; }
.grade-badge.regular { background: #f0fdf4; color: #16a34a; }
.grade-badge.instructor { background: #fef3c7; color: #d97706; }
.grade-badge.admin { background: #ede9fe; color: #7c3aed; }