/* ============================================
   SecureKeyHub Dashboard — Linear Design System
   ============================================ */

/* Font */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

/* CSS Reset & Base */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  /* Backgrounds */
  --bg-canvas: #010102;
  --bg-page: #08090a;
  --bg-panel: #0f1011;
  --bg-surface: #191a1b;
  --bg-surface-hover: #28282c;
  
  /* Text */
  --text-primary: #f7f8f8;
  --text-secondary: #d0d6e0;
  --text-tertiary: #8a8f98;
  --text-quaternary: #62666d;
  
  /* Brand */
  --brand-bg: #5e6ad2;
  --brand-accent: #7170ff;
  --brand-hover: #828fff;
  
  /* Status */
  --success: #10b981;
  --warning: #f59e0b;
  --error: #ef4444;
  --info: #3b82f6;
  
  /* Borders */
  --border-subtle: rgba(255,255,255,0.05);
  --border-default: rgba(255,255,255,0.08);
  --border-solid: #23252a;
  
  /* Shadows */
  --shadow-sm: rgba(0,0,0,0.03) 0px 1.2px 0px;
  --shadow-md: rgba(0,0,0,0.2) 0px 0px 0px 1px;
  --shadow-lg: rgba(0,0,0,0.4) 0px 2px 4px;
  --shadow-dialog: rgba(0,0,0,0) 0px 8px 2px, rgba(0,0,0,0.01) 0px 5px 2px, rgba(0,0,0,0.04) 0px 3px 2px, rgba(0,0,0,0.07) 0px 1px 1px, rgba(0,0,0,0.08) 0px 0px 1px;
  
  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  
  /* Sizes */
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-xl: 12px;
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
}

html, body {
  height: 100%;
  font-family: var(--font-sans);
  background: var(--bg-page);
  color: var(--text-primary);
  font-feature-settings: 'cv01', 'ss03';
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ========== Scrollbar ========== */
::-webkit-scrollbar {
  width: 6px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: rgba(255,255,255,0.08);
  border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
  background: rgba(255,255,255,0.12);
}

/* ========== Layout ========== */
.app-container {
  display: flex;
  min-height: 100vh;
}

/* ========== Sidebar ========== */
.sidebar {
  width: 240px;
  background: var(--bg-panel);
  border-right: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
}

.sidebar-header {
  padding: 20px 16px;
  border-bottom: 1px solid var(--border-subtle);
}

.sidebar-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.3px;
}

.sidebar-logo svg {
  width: 28px;
  height: 28px;
}

.sidebar-nav {
  padding: 12px 8px;
  flex: 1;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  border-radius: var(--radius-md);
  color: var(--text-tertiary);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  margin-bottom: 2px;
}

.nav-item:hover {
  background: rgba(255,255,255,0.04);
  color: var(--text-secondary);
}

.nav-item.active {
  background: rgba(255,255,255,0.06);
  color: var(--text-primary);
}

.nav-item svg {
  width: 18px;
  height: 18px;
  opacity: 0.7;
}

.nav-item.active svg {
  opacity: 1;
}

.sidebar-footer {
  padding: 12px 8px;
  border-top: 1px solid var(--border-subtle);
}

/* ========== Main Content ========== */
.main-content {
  flex: 1;
  padding: 32px;
  overflow-y: auto;
  max-width: 1200px;
}

.page-header {
  margin-bottom: 32px;
}

.page-title {
  font-size: 24px;
  font-weight: 500;
  color: var(--text-primary);
  letter-spacing: -0.3px;
  margin-bottom: 4px;
}

.page-subtitle {
  font-size: 15px;
  color: var(--text-tertiary);
  font-weight: 400;
}

/* ========== Stats Cards ========== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
  margin-bottom: 32px;
}

.stat-card {
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: 20px;
  transition: all var(--transition-fast);
}

.stat-card:hover {
  background: rgba(255,255,255,0.04);
}

.stat-label {
  font-size: 13px;
  font-weight: 500;
  color: var(--text-tertiary);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.stat-value {
  font-size: 28px;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.5px;
  line-height: 1.2;
}

.stat-value.positive { color: var(--success); }
.stat-value.warning { color: var(--warning); }
.stat-value.error { color: var(--error); }

.stat-change {
  font-size: 12px;
  font-weight: 500;
  color: var(--text-quaternary);
  margin-top: 4px;
}

/* ========== Cards & Panels ========== */
.card {
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  margin-bottom: 24px;
}

.card-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.card-title {
  font-size: 16px;
  font-weight: 500;
  color: var(--text-primary);
}

.card-body {
  padding: 20px;
}

/* ========== Buttons ========== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 500;
  font-family: var(--font-sans);
  cursor: pointer;
  transition: all var(--transition-fast);
  border: none;
  outline: none;
  text-decoration: none;
  line-height: 1;
}

.btn-primary {
  background: var(--brand-bg);
  color: #fff;
}
.btn-primary:hover {
  background: var(--brand-hover);
}

.btn-ghost {
  background: rgba(255,255,255,0.02);
  color: var(--text-secondary);
  border: 1px solid var(--border-solid);
}
.btn-ghost:hover {
  background: rgba(255,255,255,0.05);
  color: var(--text-primary);
}

.btn-danger {
  background: rgba(239,68,68,0.1);
  color: var(--error);
  border: 1px solid rgba(239,68,68,0.2);
}
.btn-danger:hover {
  background: rgba(239,68,68,0.2);
}

.btn-sm {
  padding: 4px 10px;
  font-size: 12px;
}

.btn-icon {
  width: 32px;
  height: 32px;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: rgba(255,255,255,0.03);
  border: 1px solid var(--border-default);
  color: var(--text-tertiary);
  cursor: pointer;
  transition: all var(--transition-fast);
}
.btn-icon:hover {
  background: rgba(255,255,255,0.08);
  color: var(--text-primary);
}

/* ========== Forms ========== */
.form-group {
  margin-bottom: 16px;
}

.form-label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.form-input {
  width: 100%;
  padding: 10px 14px;
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 14px;
  font-family: var(--font-sans);
  outline: none;
  transition: border-color var(--transition-fast);
}

.form-input:focus {
  border-color: var(--brand-bg);
}

.form-input::placeholder {
  color: var(--text-quaternary);
}

/* ========== Tables ========== */
.table-wrapper {
  overflow-x: auto;
}

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

th {
  text-align: left;
  padding: 10px 16px;
  font-size: 12px;
  font-weight: 500;
  color: var(--text-quaternary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  border-bottom: 1px solid var(--border-subtle);
}

td {
  padding: 12px 16px;
  font-size: 14px;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-subtle);
}

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

/* ========== Badges ========== */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 8px;
  border-radius: 9999px;
  font-size: 12px;
  font-weight: 500;
}

.badge-success {
  background: rgba(16,185,129,0.1);
  color: var(--success);
}

.badge-warning {
  background: rgba(245,158,11,0.1);
  color: var(--warning);
}

.badge-error {
  background: rgba(239,68,68,0.1);
  color: var(--error);
}

.badge-info {
  background: rgba(59,130,246,0.1);
  color: var(--info);
}

.badge-neutral {
  background: rgba(255,255,255,0.05);
  color: var(--text-tertiary);
}

/* ========== Key Display ========== */
.key-display {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--text-secondary);
  background: rgba(255,255,255,0.02);
  padding: 8px 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  word-break: break-all;
}

.key-display .copy-btn {
  flex-shrink: 0;
  cursor: pointer;
  color: var(--text-quaternary);
  transition: color var(--transition-fast);
}
.key-display .copy-btn:hover {
  color: var(--text-primary);
}

/* ========== Login Page ========== */
.login-page {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background: var(--bg-page);
}

.login-card {
  width: 400px;
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: 40px;
}

.login-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 32px;
  justify-content: center;
}

.login-logo svg {
  width: 36px;
  height: 36px;
}

.login-logo span {
  font-size: 22px;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

.login-title {
  font-size: 20px;
  font-weight: 500;
  color: var(--text-primary);
  text-align: center;
  margin-bottom: 8px;
}

.login-desc {
  font-size: 14px;
  color: var(--text-tertiary);
  text-align: center;
  margin-bottom: 24px;
  line-height: 1.5;
}

.login-error {
  background: rgba(239,68,68,0.1);
  border: 1px solid rgba(239,68,68,0.2);
  border-radius: var(--radius-md);
  padding: 10px 14px;
  color: var(--error);
  font-size: 13px;
  margin-bottom: 16px;
  display: none;
}

.login-error.visible {
  display: block;
}

/* ========== Modal ========== */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0,0,0,0.85);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

.modal-overlay.visible {
  opacity: 1;
  visibility: visible;
}

.modal {
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: 24px;
  width: 480px;
  max-width: 90vw;
  box-shadow: var(--shadow-dialog);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
}

.modal-title {
  font-size: 18px;
  font-weight: 500;
  color: var(--text-primary);
}

.modal-close {
  cursor: pointer;
  color: var(--text-tertiary);
  transition: color var(--transition-fast);
  background: none;
  border: none;
  font-size: 20px;
}
.modal-close:hover {
  color: var(--text-primary);
}

.modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
  margin-top: 24px;
  padding-top: 16px;
  border-top: 1px solid var(--border-subtle);
}

/* ========== Toast ========== */
.toast-container {
  position: fixed;
  top: 16px;
  right: 16px;
  z-index: 2000;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toast {
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  padding: 12px 16px;
  font-size: 14px;
  color: var(--text-primary);
  box-shadow: var(--shadow-dialog);
  display: flex;
  align-items: center;
  gap: 8px;
  animation: toastIn 300ms ease;
  min-width: 280px;
}

.toast.success { border-left: 3px solid var(--success); }
.toast.error { border-left: 3px solid var(--error); }
.toast.info { border-left: 3px solid var(--info); }

@keyframes toastIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

/* ========== Empty State ========== */
.empty-state {
  text-align: center;
  padding: 48px 24px;
  color: var(--text-tertiary);
}

.empty-state svg {
  width: 48px;
  height: 48px;
  opacity: 0.3;
  margin-bottom: 16px;
}

.empty-state h3 {
  font-size: 16px;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.empty-state p {
  font-size: 14px;
  color: var(--text-tertiary);
  max-width: 400px;
  margin: 0 auto 16px;
}

/* ========== Loading ========== */
.loading {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 48px;
}

.spinner {
  width: 24px;
  height: 24px;
  border: 2px solid var(--border-subtle);
  border-top-color: var(--brand-accent);
  border-radius: 50%;
  animation: spin 800ms linear infinite;
}

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

/* ========== Responsive ========== */
@media (max-width: 768px) {
  .sidebar {
    width: 60px;
    overflow: hidden;
  }
  .sidebar-logo span,
  .nav-item span {
    display: none;
  }
  .sidebar-logo {
    justify-content: center;
  }
  .nav-item {
    justify-content: center;
    padding: 10px;
  }
  .main-content {
    padding: 16px;
  }
  .stats-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 480px) {
  .stats-grid {
    grid-template-columns: 1fr;
  }
  .login-card {
    width: 100%;
    margin: 16px;
    padding: 24px;
  }
}

/* ========== Usage Chart (simple bar) ========== */
.usage-chart {
  display: flex;
  align-items: flex-end;
  gap: 8px;
  height: 120px;
  padding: 16px 0;
}

.chart-bar {
  flex: 1;
  background: var(--brand-bg);
  border-radius: 3px 3px 0 0;
  min-height: 4px;
  transition: height var(--transition-normal);
  position: relative;
  opacity: 0.6;
}

.chart-bar:hover {
  opacity: 1;
}

.chart-bar-label {
  position: absolute;
  bottom: -20px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 10px;
  color: var(--text-quaternary);
  white-space: nowrap;
}

/* ========== Provider Status ========== */
.provider-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
}

.provider-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
}

.provider-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 600;
}

.provider-info {
  flex: 1;
}

.provider-name {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
}

.provider-status {
  font-size: 12px;
  color: var(--text-quaternary);
}

/* ========== Recharge ========== */
.recharge-amounts {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin-bottom: 16px;
}

.recharge-option {
  padding: 12px;
  text-align: center;
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
  font-size: 14px;
  color: var(--text-secondary);
}

.recharge-option:hover,
.recharge-option.selected {
  background: rgba(94,106,210,0.1);
  border-color: var(--brand-bg);
  color: var(--text-primary);
}

.recharge-option .amount {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
}

.recharge-option .label {
  font-size: 11px;
  color: var(--text-quaternary);
  margin-top: 4px;
}

/* Page sections */
.page-section {
  display: none;
}

.page-section.active {
  display: block;
}

/* Toast close button */
.toast .toast-close {
  margin-left: auto;
  cursor: pointer;
  color: var(--text-quaternary);
  background: none;
  border: none;
  font-size: 16px;
}
.toast .toast-close:hover {
  color: var(--text-primary);
}

/* Key input group */
.input-group {
  display: flex;
  gap: 8px;
}
.input-group .form-input {
  flex: 1;
}

/* Copy feedback */
.copied-feedback {
  font-size: 11px;
  color: var(--success);
  margin-left: 8px;
  display: none;
}
.copied-feedback.visible {
  display: inline;
}