body {
  background:
    radial-gradient(circle at 12% 18%, rgba(255, 255, 255, .7) 0 120px, transparent 121px),
    radial-gradient(circle at 88% 82%, rgba(233, 103, 62, .12) 0 180px, transparent 181px),
    linear-gradient(160deg, #cfeae7 0%, #e7f4f1 55%, #fdf0e6 100%);
}

.login-shell {
  display: grid;
  grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr);
  gap: 32px;
  max-width: 1180px;
  margin: 0 auto;
  padding: 40px 24px;
  min-height: 100vh;
  align-items: center;
}

/* ---- 左側主視覺 ---- */

.hero { display: grid; gap: 28px; align-content: center; }
.hero-brand { display: grid; gap: 2px; color: var(--teal-deep); }
.hero-english { font-size: 40px; font-weight: 900; letter-spacing: .04em; line-height: 1; color: var(--teal); }
.hero-brand span { font-size: 15px; color: var(--ink-soft); }
.hero-brand b { color: var(--ink); }

.hero-orbit {
  position: relative;
  width: min(340px, 80vw);
  aspect-ratio: 1;
  margin: 0 auto;
  border-radius: 50%;
  background: radial-gradient(circle, #fff 0 38%, rgba(255, 255, 255, .45) 39% 62%, transparent 63%);
  animation: orbit 30s linear infinite;
}
.hero-orbit span {
  position: absolute;
  display: grid;
  place-items: center;
  width: 64px;
  height: 64px;
  margin: -32px;
  border-radius: 20px;
  background: var(--paper);
  font-size: 32px;
  box-shadow: var(--shadow-soft);
  animation: orbit 30s linear infinite reverse;
}
.hero-orbit span:nth-child(1) { left: 50%; top: 4%; }
.hero-orbit span:nth-child(2) { left: 94%; top: 36%; }
.hero-orbit span:nth-child(3) { left: 78%; top: 90%; }
.hero-orbit span:nth-child(4) { left: 22%; top: 90%; }
.hero-orbit span:nth-child(5) { left: 6%; top: 36%; }
.hero-island {
  position: absolute;
  inset: 32%;
  display: grid;
  place-items: center;
  font-size: 84px;
  animation: orbit 30s linear infinite reverse, bob 3s ease-in-out infinite;
}
@keyframes orbit { to { transform: rotate(360deg); } }
@keyframes bob { 50% { translate: 0 -8px; } }

.hero-copy h1 { margin: 6px 0 10px; font-size: clamp(34px, 5vw, 52px); line-height: 1.15; font-weight: 900; }
.hero-copy p:last-child { margin: 0; color: var(--ink-soft); font-size: 17px; }

/* ---- 右側報到卡 ---- */

.checkin { padding: 28px; display: grid; gap: 22px; }
.checkin-head { display: flex; justify-content: space-between; align-items: flex-end; gap: 12px; flex-wrap: wrap; }
.checkin-head h2 { margin: 2px 0 0; font-size: 28px; font-weight: 900; }
.session-pill {
  padding: 6px 14px;
  border-radius: 999px;
  background: var(--teal-mist);
  color: var(--teal-deep);
  font-weight: 700;
  font-size: 14px;
}
.session-pill.is-closed { background: #fff3d6; color: #8a5a0b; }

.step { display: grid; gap: 12px; }
.step-head { display: grid; grid-template-columns: auto 1fr auto; gap: 12px; align-items: center; }
.step-head h3 { margin: 0; font-size: 18px; }
.step-head p { margin: 0; font-size: 13px; color: var(--muted); }
.step-number {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 12px;
  background: var(--coral);
  color: #fff;
  font-weight: 900;
  font-size: 18px;
  box-shadow: 0 3px 0 var(--coral-deep);
}
.step-summary {
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--cream);
  border: 1px solid var(--line);
  font-size: 13px;
  font-weight: 700;
  color: var(--muted);
  white-space: nowrap;
}
.step-summary.is-set { background: var(--teal-mist); border-color: transparent; color: var(--teal-deep); }

.seat-grid { display: grid; grid-template-columns: repeat(10, minmax(0, 1fr)); gap: 6px; }
.seat-button {
  aspect-ratio: 1;
  min-height: 34px;
  border: 2px solid var(--line);
  border-radius: 10px;
  background: var(--cream);
  font-weight: 800;
  font-size: 15px;
  transition: transform .12s, background .12s, border-color .12s;
}
.seat-button:hover:not(:disabled) { border-color: var(--teal); transform: translateY(-2px); }
.seat-button.is-selected { background: var(--teal); border-color: var(--teal-deep); color: #fff; }
.seat-button.is-occupied {
  background: repeating-linear-gradient(135deg, #eee6dc 0 6px, #f6f0e8 6px 12px);
  color: #bfb3a6;
  border-color: #eee6dc;
  text-decoration: line-through;
}

.animal-grid { display: grid; grid-template-columns: repeat(8, minmax(0, 1fr)); gap: 8px; }
.animal-button {
  display: grid;
  justify-items: center;
  gap: 2px;
  padding: 10px 4px 8px;
  border: 2px solid var(--line);
  border-radius: 16px;
  background: var(--cream);
  transition: transform .12s, border-color .12s, background .12s;
}
.animal-button span { font-size: 30px; line-height: 1.1; }
.animal-button b { font-size: 13px; }
.animal-button:hover { border-color: var(--teal); transform: translateY(-2px); }
.animal-button.is-selected { border-color: var(--coral); background: var(--coral-soft); }

.color-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 8px; }
.color-button {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 46px;
  border: 2px solid var(--line);
  border-radius: 14px;
  background: var(--cream);
  font-weight: 700;
  font-size: 14px;
}
.color-button i { width: 18px; height: 18px; border-radius: 50%; box-shadow: inset 0 -2px 0 rgba(0, 0, 0, .15); }
.color-button:hover { border-color: var(--teal); }
.color-button.is-selected { border-color: var(--ink); background: #fff; box-shadow: var(--shadow-soft); }

.preview {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 16px;
  align-items: center;
  padding: 16px;
  border-radius: var(--radius);
  background: var(--teal-mist);
}
.preview-avatar {
  display: grid;
  place-items: center;
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: #fff;
  border: 5px solid #70aeb0;
  font-size: 34px;
  transition: border-color .2s, transform .2s;
}
.preview-avatar.is-ready { animation: hop .5s ease; }
@keyframes hop { 40% { transform: translateY(-8px) scale(1.06); } }
.preview-copy { display: grid; gap: 2px; min-width: 0; }
.preview-copy small { color: var(--muted); font-weight: 700; }
.preview-copy strong { font-size: 18px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.preview-progress { display: flex; align-items: center; gap: 10px; font-size: 13px; color: var(--ink-soft); font-weight: 700; }
.preview-progress i { flex: 1; height: 8px; border-radius: 99px; background: #fff; overflow: hidden; }
.preview-progress em { display: block; width: 0; height: 100%; background: linear-gradient(90deg, var(--teal), var(--coral)); transition: width .3s; }

.login-message {
  margin: 0;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  background: var(--cream);
  color: var(--muted);
  font-size: 14px;
  font-weight: 700;
}
.login-message.is-online { background: #e5f4ec; color: #2c7a54; }
.login-message.is-error { background: #fde6e3; color: #b23a2f; }
.login-message.is-notice { background: #fff3d6; color: #8a5a0b; }

.teacher-link {
  grid-column: 1 / -1;
  justify-self: end;
  margin-top: -12px;
  font-size: 13px;
  font-weight: 700;
  color: var(--muted);
  text-decoration: none;
}
.teacher-link:hover { color: var(--teal-deep); text-decoration: underline; }

@media (max-width: 900px) {
  .login-shell { grid-template-columns: 1fr; padding: 24px 16px; gap: 20px; }
  .hero { grid-template-columns: auto 1fr; align-items: center; gap: 16px; }
  .hero-brand { grid-column: 1 / -1; }
  .hero-orbit { width: 130px; }
  .hero-orbit span { width: 34px; height: 34px; margin: -17px; font-size: 18px; border-radius: 10px; }
  .hero-island { font-size: 40px; }
  .hero-copy h1 { font-size: 28px; }
  .hero-copy h1 br { display: none; }
  .hero-copy p:last-child { font-size: 15px; }
}

@media (max-width: 560px) {
  .checkin { padding: 20px 16px; }
  .hero-copy h1 { font-size: 23px; }
  .seat-grid { grid-template-columns: repeat(8, minmax(0, 1fr)); }
  .animal-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .color-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .step-head { grid-template-columns: auto 1fr; }
  .step-summary { grid-column: 2; justify-self: start; }
  .preview { grid-template-columns: auto 1fr; }
  .start-button { grid-column: 1 / -1; width: 100%; }
}