:root {
  --bg: #f0fdf4;
  --surface: #ffffff;
  --border: #d1fae5;
  --text: #1e293b;
  --text-muted: #64748b;
  --primary: #059669;
  --primary-hover: #047857;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(15, 23, 42, 0.08), 0 4px 16px rgba(15, 23, 42, 0.04);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  min-height: 100vh;
}

.hidden { display: none !important; }

.header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: 900px;
  margin: 0 auto;
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 1.05rem; color: var(--primary-hover); }
.logo-icon { font-size: 1.4rem; }

.main { max-width: 900px; margin: 0 auto; padding: 20px 16px 40px; }

.hero { text-align: center; margin-bottom: 28px; }
.hero-compact h1 { font-size: 1.5rem; color: var(--primary-hover); margin-bottom: 8px; }
.hero p { color: var(--text-muted); font-size: 14px; }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px 20px;
  margin-bottom: 16px;
}

.card h2 { font-size: 15px; margin-bottom: 12px; }
.card label { display: block; font-size: 13px; color: var(--text-muted); margin-bottom: 6px; }
.card input[type="text"], .card input[type="password"] {
  width: 100%; padding: 10px 12px; border: 1px solid var(--border); border-radius: 8px; font-size: 15px; margin-bottom: 12px;
}

.join-card { max-width: 420px; margin: 0 auto 24px; }

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 10px 16px; border-radius: 8px; border: 1px solid var(--border);
  background: #fff; color: var(--text); font-size: 14px; cursor: pointer; text-decoration: none;
}
.btn-primary { background: var(--primary); border-color: var(--primary); color: #fff; width: 100%; }
.btn-ghost { background: transparent; border-color: transparent; color: var(--text-muted); }
.btn-sm { padding: 6px 12px; font-size: 13px; width: auto; }
.btn-admin-entry { min-height: 44px; min-width: 120px; padding: 10px 20px; }

.home-admin-entry { text-align: center; margin-top: 16px; }

.card-grid { display: grid; gap: 16px; }
.card-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; }
.card-head-actions { display: flex; gap: 8px; }
.hint { font-size: 13px; color: var(--text-muted); }
.badge { font-size: 12px; background: #ecfdf5; color: var(--primary-hover); padding: 2px 8px; border-radius: 6px; margin-left: 6px; }

.session-list { display: flex; flex-direction: column; gap: 10px; }
.session-item {
  border: 1px solid var(--border); border-radius: 10px; padding: 12px 14px;
  display: flex; flex-direction: column; gap: 6px;
}
.session-item-actions { display: flex; gap: 8px; margin-top: 4px; }

.site-footer { text-align: center; padding: 24px; color: var(--text-muted); font-size: 13px; }

.toast {
  position: fixed; bottom: 24px; left: 50%; transform: translateX(-50%);
  background: #1e293b; color: #fff; padding: 10px 18px; border-radius: 8px;
  font-size: 14px; z-index: 9999; box-shadow: 0 4px 20px rgba(0,0,0,0.2);
}

.modal {
  position: fixed; inset: 0; background: rgba(15,23,42,0.45);
  display: flex; align-items: center; justify-content: center; z-index: 1000; padding: 16px;
}
.modal-card {
  background: #fff; border-radius: 12px; padding: 22px; max-width: 400px; width: 100%;
}
.modal-card h2 { margin-bottom: 8px; font-size: 17px; }
.modal-card input { width: 100%; padding: 10px; border: 1px solid var(--border); border-radius: 8px; margin: 12px 0; }
.modal-actions { display: flex; gap: 8px; justify-content: flex-end; margin-top: 12px; }
.pin-display { font-size: 1.2rem; color: var(--primary-hover); letter-spacing: 2px; }