:root {
  --bg: #f8fafc;
  --card: #ffffff;
  --text: #0f172a;
  --muted: #64748b;
  --line: #e2e8f0;
  --primary: #0f172a;
  --danger: #dc2626;
  --success: #059669;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: "Pretendard", "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.page-shell {
  width: 100%;
  max-width: 420px;
  min-height: 100vh;
  margin: 0 auto;
  background: var(--card);
  box-shadow: 0 20px 50px rgba(15, 23, 42, 0.12);
}

.page-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
  padding: 14px 16px;
  background: #fff;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.brand-badge {
  width: 32px;
  height: 32px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--primary);
  color: #fff;
  font-weight: 700;
}

.brand-title {
  margin: 0;
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.page-content {
  padding: 20px 16px 28px;
}

.card {
  border: 1px solid var(--line);
  background: #fff;
  padding: 16px;
}

.card + .card {
  margin-top: 12px;
}

h2,
h3,
h4,
p {
  margin: 0;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 12px;
}

.field label {
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
}

input,
button,
textarea {
  font: inherit;
}

input[type="text"],
input[type="password"],
input[type="file"],
textarea {
  width: 100%;
  border: 1px solid var(--line);
  padding: 12px;
  outline: none;
  background: #fff;
}

input:focus,
textarea:focus {
  border-color: #0f172a;
}

button {
  cursor: pointer;
}

.btn {
  border: 1px solid var(--line);
  background: #fff;
  color: var(--text);
  padding: 11px 12px;
  font-size: 14px;
  font-weight: 600;
}

.btn-primary {
  border-color: var(--primary);
  background: var(--primary);
  color: #fff;
}

.btn-danger {
  border-color: #fecaca;
  color: var(--danger);
  background: #fff;
}

.btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.row {
  display: flex;
  gap: 8px;
}

.row > * {
  flex: 1;
}

.muted {
  color: var(--muted);
  font-size: 13px;
}

.notice {
  margin-top: 12px;
  padding: 10px 12px;
  font-size: 13px;
  border: 1px solid var(--line);
  background: #f8fafc;
}

.notice.error {
  border-color: #fecaca;
  color: var(--danger);
  background: #fff1f2;
}

.notice.success {
  border-color: #a7f3d0;
  color: var(--success);
  background: #ecfdf5;
}

.user-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border: 1px solid var(--line);
}

.user-item {
  padding: 14px;
  border-bottom: 1px solid #f1f5f9;
}

.user-item:last-child {
  border-bottom: 0;
}

.user-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
}

.user-id {
  font-size: 14px;
  font-weight: 700;
}

.user-name {
  color: var(--muted);
  font-size: 13px;
}

.status {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 8px;
  font-size: 12px;
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 999px;
  background: #94a3b8;
}

.status-dot.active {
  background: #16a34a;
}

.user-actions {
  display: flex;
  gap: 8px;
  margin-top: 10px;
}

.meta {
  margin-top: 10px;
  font-size: 12px;
  color: var(--muted);
}

.top-gap {
  margin-top: 14px;
}