:root {
  /* Brand Color Palette */
  --primary: #6C5CE7;
  --primary-dark: #5546C7;
  --primary-light: #ECE9FD;
  --accent: #8B7CF6;
  --accent-light: #F3F1FE;
  
  /* Semantic Colors */
  --success: #10B981;
  --success-light: #D1FAE5;
  --warning: #F59E0B;
  --warning-light: #FEF3C7;
  --error: #EF4444;
  --error-light: #FEE2E2;
  --info: #3B82F6;
  --info-light: #DBEAFE;
  
  /* Light Theme (Default) */
  --bg-app: #F8F9FC;
  --bg-surface: #FFFFFF;
  --bg-subtle: #F1F3F9;
  --bg-hover: #F3F4F8;
  
  --text-main: #171923;
  --text-secondary: #6B7280;
  --text-muted: #9CA3AF;
  --text-inverse: #FFFFFF;
  
  --border-color: #E8EAF0;
  --border-focus: #6C5CE7;
  --divider: #EDF0F7;
  
  /* Elevation Shadows */
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 10px 24px rgba(108, 92, 231, 0.12);
  --shadow-xl: 0 20px 35px rgba(0, 0, 0, 0.14);
  
  /* Radii */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 22px;
  --radius-full: 9999px;
  
  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

[data-theme="dark"] {
  --bg-app: #0E101B;
  --bg-surface: #17192A;
  --bg-subtle: #1F2338;
  --bg-hover: #262B45;
  
  --text-main: #F8FAFC;
  --text-secondary: #94A3B8;
  --text-muted: #64748B;
  --text-inverse: #0E101B;
  
  --border-color: #272B44;
  --border-focus: #8B7CF6;
  --divider: #21253B;
  
  --primary-light: rgba(108, 92, 231, 0.2);
  --accent-light: rgba(139, 124, 246, 0.18);
  --success-light: rgba(16, 185, 129, 0.18);
  --warning-light: rgba(245, 158, 11, 0.18);
  --error-light: rgba(239, 68, 68, 0.18);
  
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-sm: 0 2px 5px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 6px 14px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 12px 28px rgba(0, 0, 0, 0.55);
}

/* Base Reset */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

body {
  font-family: var(--font-family);
  background-color: #0E101B;
  color: var(--text-main);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* Typography Helpers */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  color: var(--text-main);
  letter-spacing: -0.02em;
}

p {
  color: var(--text-secondary);
}

/* Button System */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  font-size: 14px;
  font-weight: 600;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.15s ease-in-out;
  text-decoration: none;
  min-height: 44px; /* Touch-friendly mobile target */
  user-select: none;
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background-color: var(--primary);
  color: #ffffff;
  box-shadow: 0 3px 8px rgba(108, 92, 231, 0.35);
}

.btn-primary:hover {
  background-color: var(--primary-dark);
}

.btn-secondary {
  background-color: var(--bg-subtle);
  color: var(--text-main);
  border-color: var(--border-color);
}

.btn-secondary:hover {
  background-color: var(--bg-hover);
}

.btn-outline {
  background-color: transparent;
  color: var(--primary);
  border-color: var(--primary);
}

.btn-outline:hover {
  background-color: var(--primary-light);
}

.btn-success {
  background-color: var(--success);
  color: #ffffff;
}

.btn-danger {
  background-color: var(--error);
  color: #ffffff;
}

.btn-sm {
  padding: 6px 12px;
  font-size: 12px;
  min-height: 34px;
  border-radius: var(--radius-sm);
}

.btn-lg {
  padding: 14px 22px;
  font-size: 16px;
  min-height: 50px;
  border-radius: var(--radius-md);
}

.btn-block {
  width: 100%;
}

.btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
  transform: none;
}

/* Badge System */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 4px 10px;
  font-size: 12px;
  font-weight: 600;
  border-radius: var(--radius-full);
  line-height: 1;
}

.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
}

.badge-primary {
  background-color: var(--primary-light);
  color: var(--primary);
}

.badge-success {
  background-color: var(--success-light);
  color: var(--success);
}
.badge-success .badge-dot { background-color: var(--success); }

.badge-warning {
  background-color: var(--warning-light);
  color: var(--warning);
}
.badge-warning .badge-dot { background-color: var(--warning); }

.badge-error {
  background-color: var(--error-light);
  color: var(--error);
}
.badge-error .badge-dot { background-color: var(--error); }

.badge-neutral {
  background-color: var(--bg-subtle);
  color: var(--text-secondary);
}

.badge-info {
  background-color: var(--info-light);
  color: var(--info);
}

/* Form Controls */
.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 16px;
}

.form-label {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-main);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.form-label-hint {
  font-size: 11px;
  font-weight: 500;
  color: var(--text-muted);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 12px 14px;
  font-size: 14px;
  font-family: inherit;
  color: var(--text-main);
  background-color: var(--bg-surface);
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-md);
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
  min-height: 46px;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-light);
}

.form-input::placeholder,
.form-textarea::placeholder {
  color: var(--text-muted);
}

/* Card Shells */
.card {
  background-color: var(--bg-surface);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  padding: 18px;
  transition: transform 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease;
}

/* Modal and Bottom Sheet */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background-color: rgba(15, 17, 26, 0.65);
  backdrop-filter: blur(4px);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease;
}

.modal-backdrop.active {
  opacity: 1;
  visibility: visible;
}

.modal-sheet {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  width: 100%;
  max-width: 520px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-xl);
  transform: translateY(20px) scale(0.97);
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  padding: 22px;
  position: relative;
}

.modal-backdrop.active .modal-sheet {
  transform: translateY(0) scale(1);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 18px;
}

.modal-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-main);
}

.modal-close {
  background: transparent;
  border: none;
  font-size: 22px;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px;
  line-height: 1;
  border-radius: var(--radius-sm);
}

.modal-close:hover {
  color: var(--text-main);
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  top: 70px;
  right: 20px;
  z-index: 2000;
  display: flex;
  flex-direction: column;
  gap: 10px;
  pointer-events: none;
}

.toast {
  background-color: var(--bg-surface);
  color: var(--text-main);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  padding: 12px 18px;
  font-size: 13.5px;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 10px;
  pointer-events: auto;
  animation: slideInToast 0.25s cubic-bezier(0.16, 1, 0.3, 1) forwards;
  min-width: 280px;
  max-width: 400px;
}

@keyframes slideInToast {
  from {
    opacity: 0;
    transform: translateY(-10px) scale(0.95);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}