:root {
  --bg-dark: #000000;
  --sidebar-bg: #0a0a0a;
  --card-bg: rgba(20, 20, 20, 0.6);
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --accent-primary: #FFC407;
  --accent-green: #4ade80;
  --accent-purple: #c084fc;
  --accent-red: #f87171;
  --accent-amber: #FFC407;
  --border-color: rgba(255, 196, 7, 0.12);
  --sidebar-width: 260px;
  --glass-blur: blur(12px);
  --grad-primary: linear-gradient(135deg, #FFC407 0%, #CC9D06 100%);
  --shadow-premium: 0 10px 25px -5px rgba(0, 0, 0, 0.5), 0 8px 10px -6px rgba(0, 0, 0, 0.4);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Montserrat", system-ui, -apple-system, sans-serif;
}

body {
  background-color: var(--bg-dark);
  color: var(--text-main);
  overflow-x: hidden;
}

#app {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background-color: var(--sidebar-bg);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  position: fixed;
  height: 100vh;
  box-shadow: 10px 0 30px rgba(0, 0, 0, 0.2);
  z-index: 100;
}

.sidebar-header {
  padding: 2.5rem 2rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.logo-icon {
  color: var(--accent-primary);
  width: 28px;
  height: 28px;
  filter: drop-shadow(0 0 8px rgba(255, 196, 7, 0.4));
}

.logo-text {
  font-size: 1.2rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  background: var(--grad-primary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-links {
  list-style: none;
  padding: 1rem 0.75rem;
  flex-grow: 1;
}

.nav-links li {
  padding: 0.875rem 1.25rem;
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  border-radius: 0.75rem;
  cursor: pointer;
  color: var(--text-muted);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  font-size: 0.9375rem;
  font-weight: 500;
}

.nav-links li:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
}

.nav-links li.active {
  background: rgba(255, 196, 7, 0.1);
  color: var(--accent-primary);
  box-shadow: inset 0 0 0 1px rgba(255, 196, 7, 0.2);
}

.sidebar-footer {
  padding: 1.5rem;
  border-top: 1px solid var(--border-color);
  background: rgba(0, 0, 0, 0.1);
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* Content Area */
.content {
  margin-left: var(--sidebar-width);
  flex-grow: 1;
  padding: 2.5rem 3rem;
  background:
    radial-gradient(circle at top right, rgba(255, 196, 7, 0.03), transparent 40%),
    radial-gradient(circle at bottom left, rgba(255, 196, 7, 0.02), transparent 40%);
}

.top-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
}

.top-bar h1 {
  font-size: 1.75rem;
  font-weight: 800;
  letter-spacing: -0.025em;
}

/* Filter Bar */
.filter-bar {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
  padding: 1rem 1.5rem;
  background: var(--card-bg);
  backdrop-filter: var(--glass-blur);
  border: 1px solid var(--border-color);
  border-radius: 1rem;
  flex-wrap: wrap;
}

.period-selector {
  display: flex;
  gap: 0.25rem;
  background: rgba(0, 0, 0, 0.2);
  padding: 0.25rem;
  border-radius: 0.5rem;
}

.period-btn {
  padding: 0.5rem 1rem;
  border: none;
  background: transparent;
  color: var(--text-muted);
  border-radius: 0.375rem;
  cursor: pointer;
  font-size: 0.875rem;
  font-weight: 600;
  transition: all 0.2s;
}

.period-btn:hover {
  color: var(--text-main);
  background: rgba(255, 255, 255, 0.05);
}

.period-btn.active {
  background: var(--accent-primary);
  color: #000000;
}

.date-range-picker {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.date-range-picker input[type="date"] {
  width: 150px;
  padding: 0.5rem 0.75rem;
  font-size: 0.875rem;
  background: #0f172a;
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  color: var(--text-main);
  outline: none;
}

.date-range-picker input[type="date"]:focus {
  border-color: var(--accent-primary);
}

.date-separator {
  color: var(--text-muted);
  font-size: 0.875rem;
}

.refresh-info {
  margin-left: auto;
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* Tabs */
.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
  animation: slideUp 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Stat Cards */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.stat-card {
  background: var(--card-bg);
  backdrop-filter: var(--glass-blur);
  border: 1px solid var(--border-color);
  padding: 1.75rem;
  border-radius: 1.25rem;
  display: flex;
  align-items: center;
  gap: 1.25rem;
  box-shadow: var(--shadow-premium);
  transition: transform 0.3s ease, border-color 0.3s ease;
}

.stat-card:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 196, 7, 0.3);
}

.stat-icon {
  width: 56px;
  height: 56px;
  border-radius: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.stat-icon svg {
  width: 24px;
  height: 24px;
}

.stat-icon.cost { background: rgba(255, 196, 7, 0.1); color: var(--accent-primary); }
.stat-icon.tokens { background: rgba(255, 196, 7, 0.08); color: #FFD54F; }
.stat-icon.users { background: rgba(192, 132, 252, 0.1); color: var(--accent-purple); }
.stat-icon.convos { background: rgba(255, 196, 7, 0.06); color: #FFAB00; }
.stat-icon.visits { background: rgba(74, 222, 128, 0.1); color: var(--accent-green); }
.stat-icon.unique { background: rgba(248, 113, 113, 0.1); color: var(--accent-red); }

.stat-label {
  display: block;
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 0.25rem;
}

.stat-value {
  font-size: 1.5rem;
  font-weight: 700;
}

/* Charts */
.charts-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.chart-wide {
  grid-column: span 2;
}

.chart-container {
  background: var(--card-bg);
  backdrop-filter: var(--glass-blur);
  border: 1px solid var(--border-color);
  padding: 1.5rem;
  border-radius: 1.25rem;
  box-shadow: var(--shadow-premium);
  position: relative;
}

.chart-container h3 {
  margin-bottom: 1rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-muted);
}

.chart-container canvas {
  width: 100% !important;
  max-height: 350px;
}

/* Tables */
.table-container {
  background: var(--card-bg);
  backdrop-filter: var(--glass-blur);
  border: 1px solid var(--border-color);
  border-radius: 1.25rem;
  overflow: hidden;
  box-shadow: var(--shadow-premium);
  margin-bottom: 2rem;
}

.table-header {
  padding: 1.5rem 2rem;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.table-header h3 {
  font-size: 1.125rem;
  font-weight: 700;
}

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

th {
  background: rgba(15, 23, 42, 0.4);
  padding: 1rem 1.5rem;
  font-weight: 600;
  font-size: 0.8125rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  text-align: left;
}

th.text-right, td.text-right {
  text-align: right;
}

td {
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
  font-size: 0.9375rem;
}

tr:hover td {
  background: rgba(255, 255, 255, 0.02);
}

.cost-value {
  color: var(--accent-primary);
  font-weight: 600;
}

.token-value {
  color: #FFD54F;
  font-weight: 500;
}

/* Export Button */
.btn-export {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background: rgba(255, 196, 7, 0.1);
  color: var(--accent-primary);
  border: 1px solid rgba(255, 196, 7, 0.2);
  border-radius: 0.5rem;
  font-family: "Montserrat", system-ui, sans-serif;
  font-size: 0.8125rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-export:hover {
  background: rgba(255, 196, 7, 0.2);
  border-color: rgba(255, 196, 7, 0.4);
}

.tab-title-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
}

/* User Search */
.user-search-bar {
  display: flex;
  gap: 0.75rem;
  align-items: center;
  margin-bottom: 1.5rem;
}

.search-input-wrap {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex: 1;
  max-width: 500px;
  padding: 0.625rem 1rem;
  background: #0f172a;
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  color: var(--text-muted);
}

.search-input-wrap input {
  flex: 1;
  background: none;
  border: none;
  outline: none;
  color: var(--text-main);
  font-family: "Montserrat", system-ui, sans-serif;
  font-size: 0.9375rem;
}

.search-input-wrap input::placeholder {
  color: var(--text-muted);
}

.search-input-wrap:focus-within {
  border-color: var(--accent-primary);
}

.search-results {
  margin-bottom: 1.5rem;
}

.search-result-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem 1.25rem;
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  margin-bottom: 0.5rem;
  cursor: pointer;
  transition: all 0.2s;
}

.search-result-item:hover {
  border-color: var(--accent-primary);
  background: rgba(255, 196, 7, 0.05);
}

.search-result-name {
  font-weight: 600;
  color: var(--accent-primary);
}

.search-result-email {
  color: var(--text-muted);
  font-size: 0.875rem;
}

/* User Links */
.user-link {
  color: var(--accent-primary);
  text-decoration: none;
  font-weight: 600;
  transition: opacity 0.2s;
}

.user-link:hover {
  opacity: 0.8;
  text-decoration: underline;
}

/* Model Tags */
.model-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.model-tag {
  display: inline-block;
  padding: 0.15rem 0.5rem;
  background: rgba(255, 196, 7, 0.08);
  border: 1px solid rgba(255, 196, 7, 0.15);
  border-radius: 0.35rem;
  font-size: 0.75rem;
  color: var(--text-muted);
  white-space: nowrap;
}

.btn-filter-user {
  background: rgba(248, 113, 113, 0.1);
  color: var(--accent-red);
  border-color: rgba(248, 113, 113, 0.2);
}

.btn-filter-user:hover {
  background: rgba(248, 113, 113, 0.2);
  border-color: rgba(248, 113, 113, 0.4);
}

/* Loading */
.loading {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 3rem;
  color: var(--text-muted);
}

.spinner {
  width: 24px;
  height: 24px;
  border: 3px solid var(--border-color);
  border-top-color: var(--accent-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin-right: 1rem;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Responsive */
@media (max-width: 1200px) {
  .charts-grid { grid-template-columns: 1fr; }
  .chart-wide { grid-column: span 1; }
}

@media (max-width: 768px) {
  .sidebar { display: none; }
  .content { margin-left: 0; padding: 1.5rem; }
  .filter-bar { flex-direction: column; align-items: stretch; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
}