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

html {
  font-size: 16px;
  line-height: 1.5;
}

body {
  font-family: -apple-system, "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
  background-color: #f5f5f5;
  color: #1f2937;
  min-height: 100vh;
}

input,
textarea,
select {
  border: 1px solid #ccc;
  padding: 6px 8px;
  border-radius: 4px;
  font-size: 14px;
  font-family: inherit;
  background-color: #fff;
  color: #1f2937;
  transition: border-color 0.15s;
}

input:focus,
textarea:focus,
select:focus {
  outline: none;
  border-color: #2563eb;
  box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.15);
}

button {
  padding: 8px 14px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 14px;
  font-family: inherit;
  border: 1px solid transparent;
  transition: background-color 0.15s, opacity 0.15s;
}

button:hover {
  opacity: 0.9;
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-primary {
  background-color: #2563eb;
  color: #fff;
  border-color: #2563eb;
}

.btn-default {
  background-color: #fff;
  color: #1f2937;
  border-color: #ccc;
}

.btn-danger {
  background-color: #ef4444;
  color: #fff;
  border-color: #ef4444;
}

table {
  border-collapse: collapse;
  width: 100%;
}

th {
  font-weight: bold;
  background-color: #e5e7eb;
  padding: 8px 12px;
  text-align: left;
  border-bottom: 2px solid #d1d5db;
}

td {
  padding: 8px 12px;
  border-bottom: 1px solid #eee;
}

a {
  color: #2563eb;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.3;
}

h1 { font-size: 24px; }
h2 { font-size: 20px; }
h3 { font-size: 18px; }
h4 { font-size: 16px; }
h5 { font-size: 14px; }
h6 { font-size: 13px; }

/* ============ App Layout ============ */
.app-layout { display: flex; min-height: 100vh; background: #f5f5f5; }
.sidebar { width: 220px; background: #1e293b; color: #e2e8f0; display: flex; flex-direction: column; flex-shrink: 0; position: sticky; top: 0; height: 100vh; overflow-y: auto; }
.sidebar-header { padding: 20px 16px; border-bottom: 1px solid #334155; }
.sidebar-title { margin: 0; font-size: 22px; font-weight: 700; color: #fff; }
.sidebar-subtitle { margin: 4px 0 0; font-size: 12px; color: #94a3b8; }
.sidebar-nav { padding: 12px 8px; display: flex; flex-direction: column; gap: 2px; }
.nav-item { display: flex; align-items: center; gap: 10px; padding: 10px 12px; border-radius: 6px; color: #cbd5e1; text-decoration: none; font-size: 14px; transition: background-color 0.15s, color 0.15s; cursor: pointer; }
.nav-item:hover { background: #334155; color: #fff; }
.nav-item-active { background: #2563eb !important; color: #fff !important; }
.nav-icon { font-size: 16px; }
.nav-label { flex: 1; }
.main-content { flex: 1; min-width: 0; padding: 24px; overflow-x: auto; background: #f5f5f5; }