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

:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-card: #1a1a2e;
  --bg-card-hover: #222240;
  --border: #2a2a45;
  --text-primary: #f0f0f5;
  --text-secondary: #8888aa;
  --accent: #e63946;
  --accent-hover: #ff4757;
  --accent-glow: rgba(230, 57, 70, 0.3);
  --gold: #f0c040;
  --success: #2ecc71;
  --warning: #f39c12;
  --danger: #e74c3c;
  --info: #3498db;
  --radius: 12px;
  --shadow: 0 4px 24px rgba(0,0,0,0.4);
}

body {
  font-family: 'Segoe UI', -apple-system, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
}

/* Belt colors */
.belt-white { color: #ffffff; }
.belt-blue { color: #1a5276; }
.belt-purple { color: #8e44ad; }
.belt-brown { color: #8b4513; }
.belt-black { color: #1a1a1a; }

.belt-badge {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 4px 12px; border-radius: 20px; font-size: 12px; font-weight: 600;
}
.belt-badge.white { background: #f5f5f5; color: #333; }
.belt-badge.blue { background: #1a5276; color: #fff; }
.belt-badge.purple { background: #8e44ad; color: #fff; }
.belt-badge.brown { background: #8b4513; color: #fff; }
.belt-badge.black { background: #1a1a1a; color: #fff; border: 1px solid #333; }

.belt-badge .stripes { display: flex; gap: 2px; }
.belt-badge .stripe { width: 8px; height: 3px; background: var(--gold); border-radius: 1px; }

/* Layout */
.app { display: flex; min-height: 100vh; }
.sidebar {
  width: 260px; background: var(--bg-secondary); border-right: 1px solid var(--border);
  padding: 20px 0; display: flex; flex-direction: column; position: fixed; height: 100vh; z-index: 100;
}
.sidebar-header { padding: 0 20px 24px; border-bottom: 1px solid var(--border); }
.sidebar-header h1 { font-size: 22px; font-weight: 800; }
.sidebar-header h1 span { color: var(--accent); }
.sidebar-header p { font-size: 12px; color: var(--text-secondary); margin-top: 4px; }

.nav-menu { flex: 1; padding: 12px 0; overflow-y: auto; }
.nav-item {
  display: flex; align-items: center; gap: 12px; padding: 12px 20px;
  color: var(--text-secondary); cursor: pointer; transition: all 0.2s;
  border-left: 3px solid transparent; font-size: 14px;
}
.nav-item:hover { background: var(--bg-card); color: var(--text-primary); }
.nav-item.active { background: var(--bg-card); color: var(--accent); border-left-color: var(--accent); }
.nav-item .icon { width: 20px; text-align: center; font-size: 16px; }

.main { flex: 1; margin-left: 260px; padding: 24px; }
.page-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 24px; }
.page-header h2 { font-size: 24px; font-weight: 700; }

/* Cards */
.card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 20px;
}
.card-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 16px; }
.card-title { font-size: 16px; font-weight: 600; }

/* Stats grid */
.stats-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; margin-bottom: 24px; }
.stat-card {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px; display: flex; flex-direction: column; gap: 8px;
}
.stat-card .stat-icon { font-size: 24px; }
.stat-card .stat-value { font-size: 28px; font-weight: 800; }
.stat-card .stat-label { font-size: 13px; color: var(--text-secondary); }
.stat-card.accent { border-color: var(--accent); background: linear-gradient(135deg, var(--bg-card), rgba(230,57,70,0.1)); }
.stat-card.success { border-color: var(--success); }
.stat-card.warning { border-color: var(--warning); }

/* Grid layouts */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.grid-3 { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 20px; }

/* Tables */
.table-container { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
th { text-align: left; padding: 12px 16px; font-size: 12px; text-transform: uppercase; color: var(--text-secondary); border-bottom: 1px solid var(--border); }
td { padding: 12px 16px; border-bottom: 1px solid var(--border); font-size: 14px; }
tr:hover td { background: var(--bg-card-hover); }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 20px; border: none; border-radius: 8px;
  font-size: 14px; font-weight: 600; cursor: pointer; transition: all 0.2s;
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-hover); box-shadow: 0 0 20px var(--accent-glow); }
.btn-secondary { background: var(--bg-card); color: var(--text-primary); border: 1px solid var(--border); }
.btn-secondary:hover { border-color: var(--accent); }
.btn-success { background: var(--success); color: #fff; }
.btn-warning { background: var(--warning); color: #fff; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-sm { padding: 6px 12px; font-size: 12px; }
.btn-icon { padding: 8px; border-radius: 8px; background: var(--bg-card); border: 1px solid var(--border); color: var(--text-secondary); cursor: pointer; }
.btn-icon:hover { color: var(--accent); border-color: var(--accent); }

/* Forms */
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-size: 13px; color: var(--text-secondary); margin-bottom: 6px; font-weight: 500; }
.form-group input, .form-group select, .form-group textarea {
  width: 100%; padding: 10px 14px; background: var(--bg-primary);
  border: 1px solid var(--border); border-radius: 8px; color: var(--text-primary);
  font-size: 14px; transition: border-color 0.2s;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
  outline: none; border-color: var(--accent);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

/* Modal */
.modal-overlay {
  position: fixed; top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.7); display: flex; align-items: center; justify-content: center;
  z-index: 1000; opacity: 0; visibility: hidden; transition: all 0.3s;
}
.modal-overlay.active { opacity: 1; visibility: visible; }
.modal {
  background: var(--bg-secondary); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px; width: 90%; max-width: 600px; max-height: 85vh; overflow-y: auto;
}
.modal-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
.modal-header h3 { font-size: 18px; font-weight: 700; }
.modal-close { background: none; border: none; color: var(--text-secondary); font-size: 24px; cursor: pointer; }
.modal-actions { display: flex; gap: 12px; justify-content: flex-end; margin-top: 20px; }

/* Tags / Badges */
.badge {
  display: inline-block; padding: 4px 10px; border-radius: 20px;
  font-size: 11px; font-weight: 600;
}
.badge-success { background: rgba(46,204,113,0.15); color: var(--success); }
.badge-warning { background: rgba(243,156,18,0.15); color: var(--warning); }
.badge-danger { background: rgba(231,76,60,0.15); color: var(--danger); }
.badge-info { background: rgba(52,152,219,0.15); color: var(--info); }

/* Search */
.search-box {
  display: flex; align-items: center; gap: 8px; background: var(--bg-primary);
  border: 1px solid var(--border); border-radius: 8px; padding: 8px 14px;
}
.search-box input { background: none; border: none; color: var(--text-primary); font-size: 14px; flex: 1; outline: none; }

/* Tabs */
.tabs { display: flex; gap: 4px; margin-bottom: 20px; background: var(--bg-primary); border-radius: 8px; padding: 4px; }
.tab {
  padding: 8px 16px; border-radius: 6px; font-size: 13px; font-weight: 500;
  color: var(--text-secondary); cursor: pointer; transition: all 0.2s;
}
.tab.active { background: var(--accent); color: #fff; }
.tab:hover:not(.active) { color: var(--text-primary); }

/* Schedule grid */
.schedule-grid { display: grid; grid-template-columns: repeat(7, 1fr); gap: 8px; }
.schedule-day { min-height: 100px; }
.schedule-day-header { font-size: 12px; font-weight: 600; color: var(--text-secondary); margin-bottom: 8px; text-align: center; }
.schedule-class {
  padding: 8px; border-radius: 6px; margin-bottom: 4px; font-size: 11px;
  border-left: 3px solid; cursor: pointer;
}
.schedule-class .time { font-weight: 700; }
.schedule-class .name { margin-top: 2px; }

/* Chart placeholder */
.chart-container { height: 200px; display: flex; align-items: flex-end; gap: 8px; padding: 16px 0; }
.chart-bar {
  flex: 1; background: linear-gradient(to top, var(--accent), var(--accent-hover));
  border-radius: 4px 4px 0 0; min-height: 4px; transition: height 0.5s;
  position: relative;
}
.chart-bar:hover { opacity: 0.8; }
.chart-bar .chart-label {
  position: absolute; bottom: -20px; left: 50%; transform: translateX(-50%);
  font-size: 10px; color: var(--text-secondary); white-space: nowrap;
}
.chart-bar .chart-value {
  position: absolute; top: -20px; left: 50%; transform: translateX(-50%);
  font-size: 11px; font-weight: 600;
}

/* Belt progress */
.belt-progress { display: flex; gap: 4px; align-items: center; }
.belt-step {
  height: 8px; flex: 1; border-radius: 4px; background: var(--border); transition: background 0.3s;
}
.belt-step.completed.white { background: #e0e0e0; }
.belt-step.completed.blue { background: #1a5276; }
.belt-step.completed.purple { background: #8e44ad; }
.belt-step.completed.brown { background: #8b4513; }
.belt-step.completed.black { background: #1a1a1a; }

/* Streak flame */
.streak { display: flex; align-items: center; gap: 4px; font-weight: 700; }
.streak.hot { color: var(--accent); }

/* Empty state */
.empty-state { text-align: center; padding: 40px; color: var(--text-secondary); }
.empty-state .icon { font-size: 48px; margin-bottom: 12px; }

/* Loading */
.loading { display: flex; justify-content: center; padding: 40px; }
.spinner { width: 32px; height: 32px; border: 3px solid var(--border); border-top-color: var(--accent); border-radius: 50%; animation: spin 0.8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

/* Toast */
.toast-container { position: fixed; top: 20px; right: 20px; z-index: 2000; display: flex; flex-direction: column; gap: 8px; }
.toast {
  padding: 12px 20px; border-radius: 8px; font-size: 14px; font-weight: 500;
  animation: slideIn 0.3s ease; box-shadow: var(--shadow);
}
.toast-success { background: var(--success); color: #fff; }
.toast-error { background: var(--danger); color: #fff; }
@keyframes slideIn { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }

/* Login page */
.login-container {
  min-height: 100vh; display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, var(--bg-primary) 0%, #1a0a0e 100%);
}
.login-card {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 40px; width: 400px; max-width: 90%;
}
.login-card h1 { text-align: center; font-size: 28px; margin-bottom: 8px; }
.login-card h1 span { color: var(--accent); }
.login-card p { text-align: center; color: var(--text-secondary); margin-bottom: 32px; font-size: 14px; }
.login-card .btn { width: 100%; justify-content: center; }

/* Responsive */
@media (max-width: 768px) {
  .sidebar { width: 60px; }
  .sidebar-header h1, .sidebar-header p, .nav-item span { display: none; }
  .nav-item { justify-content: center; padding: 12px; }
  .main { margin-left: 60px; padding: 16px; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .schedule-grid { grid-template-columns: 1fr; }
}