/* CSS Variables for Theming */
:root {
  --bg-color: #f9fafb;
  --main-bg-color: rgba(255, 255, 255, 0.75);
  --text-color: #111827;
  --text-muted-color: #6b7280;
  --border-color: #d1d5db;
  --surface-color: #ffffff;
  --surface-hover-color: #f3f4f6;
  --primary-color: #2563eb;
  --primary-hover-color: #1d4ed8;
  --primary-subtle-bg: rgba(37, 99, 235, 0.1);
  --secondary-surface-color: #f3f4f6;
  --secondary-surface-hover-color: #e5e7eb;
  --active-tab-bg: #2563eb;
  --active-tab-text: white;
  --shadow-color: rgba(0, 0, 0, 0.08);
  --success-color: #16a34a;
  --danger-color: #dc2626;
  --danger-subtle-bg: rgba(220, 38, 38, 0.1);
  --teal-color: #0d9488;
  --success-hover-color: #15803d;
  --danger-hover-color: #b91c1c;
  --teal-hover-color: #0f766e;
}

.dark {
  --bg-color: #111827;
  --main-bg-color: rgba(31, 41, 55, 0.75);
  --text-color: #f9fafb;
  --text-muted-color: #9ca3af;
  --border-color: #4b5563;
  --surface-color: #1f2937;
  --surface-hover-color: #374151;
  --primary-color: #3b82f6;
  --primary-hover-color: #60a5fa;
  --primary-subtle-bg: rgba(59, 130, 246, 0.15);
  --secondary-surface-color: #374151;
  --secondary-surface-hover-color: #4b5563;
  --active-tab-bg: #3b82f6;
  --active-tab-text: #ffffff;
  --shadow-color: rgba(0, 0, 0, 0.25);
  --success-color: #22c55e;
  --danger-color: #ef4444;
  --danger-subtle-bg: rgba(239, 68, 68, 0.15);
  --teal-color: #14b8a6;
  --success-hover-color: #16a34a;
  --danger-hover-color: #dc2626;
  --teal-hover-color: #0d9488;
}

/* Base Styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
body {
  font-family: "Poppins", sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  transition: background-color 0.3s, color 0.3s;
}

body::before {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  opacity: 0.03;
  background-image: radial-gradient(
    var(--text-muted-color) 1px,
    transparent 1px
  );
  background-size: 25px 25px;
}

/* Main Layout */
#container {
  position: relative;
  min-height: 100vh;
  width: 100%;
  padding: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

main {
  width: 100%;
  max-width: 64rem;
  background-color: var(--main-bg-color);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  padding: 1.5rem;
  border-radius: 1.5rem;
  box-shadow: 0 25px 50px -12px var(--shadow-color);
  border: 1px solid var(--border-color);
  transition: all 0.3s ease-in-out;
}

/* Header */
header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
}

h1 {
  font-size: 1.5rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  background-image: linear-gradient(to right, var(--primary-color), #14b8a6);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
h1 i {
  background: none;
  -webkit-background-clip: initial;
  background-clip: initial;
  color: var(--primary-color);
}

header .controls button {
  padding: 0.5rem;
  border-radius: 9999px;
  background: none;
  border: none;
  cursor: pointer;
  transition: background-color 0.2s;
  color: var(--text-muted-color);
}
header .controls button:hover {
  background-color: var(--surface-hover-color);
}
header .controls svg {
  width: 1.5rem;
  height: 1.5rem;
}
#theme-icon-dark {
  display: none;
}
.dark #theme-icon-dark {
  display: block;
}
.dark #theme-icon-light {
  display: none;
}

/* View & Step Styles */
.view-container {
  position: relative;
  min-height: 480px;
}
.view {
  transition: opacity 0.4s ease, transform 0.4s ease;
}
.view-hidden {
  opacity: 0;
  transform: translateY(20px);
  pointer-events: none;
  position: absolute;
  width: 100%;
  top: 0;
  left: 0;
}

h2 {
  font-size: 1.25rem;
  font-weight: 500;
  color: var(--text-color);
  margin-bottom: 1rem;
}

/* Step 1: Chart Type Selection */
#chartTypeGrid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
}
.chart-type-item {
  cursor: pointer;
  padding: 1rem;
  border: 2px solid var(--border-color);
  border-radius: 0.75rem;
  text-align: center;
  transition: all 0.2s;
}
.chart-type-item:hover {
  border-color: var(--primary-color);
  background-color: var(--surface-hover-color);
  transform: translateY(-2px);
}
.chart-type-item.selected {
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px var(--primary-color);
  background-color: var(--surface-hover-color);
}
.chart-type-item i {
  font-size: 2.5rem;
  margin: 0 auto 0.5rem;
  color: var(--text-muted-color);
  display: block;
}
.chart-type-item span {
  font-weight: 500;
}

/* Step 2: Data Entry */
.data-entry-header {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1rem;
}
.data-entry-header .actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
#data-entry-area {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

h3 {
  font-weight: 500;
  margin-bottom: 0.5rem;
}
.input-container {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  max-height: 20rem;
  overflow-y: auto;
  padding-right: 0.5rem;
}
.input-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.datasets-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
  flex-wrap: wrap;
}
#datasets-tabs {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  flex-wrap: wrap;
}
.dataset-tab {
  display: flex;
}
.dataset-tab button {
  border-radius: 0 0.375rem 0.375rem 0;
  font-size: 0.875rem;
  padding: 0.25rem 0.75rem;
  cursor: pointer;
  transition: all 0.2s;
  border: none;
  background-color: #22c55e;
}
.dataset-tab button.tab-label {
  border-radius: 0.375rem 0 0 0.375rem;
  border-right: none;
}
.dataset-tab button.tab-remove {
  border-left: none;
  padding: 0.25rem 0.5rem;
  font-size: 0.75rem;
}
.dataset-tab button.active {
  background-color: var(--active-tab-bg);
  color: var(--active-tab-text);
  border-color: var(--active-tab-bg);
}

.dataset-tab button:not(.active):hover {
  background-color: var(--secondary-surface-hover-color);
}
.dataset-color-picker {
  width: 24px;
  height: 24px;
  border: 0px solid var(--border-color);
  cursor: pointer;
  background-color: transparent;
  padding: 0;
}
.dataset-color-picker.active {
  background-color: var(--active-tab-bg) !important;
  color: var(--active-tab-text);
  border-color: var(--active-tab-bg);
}
/* Step 3: Display & Customize */
.chart-display-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}
.chart-container {
  min-height: 450px;
}
#customize-panel {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}
.customize-group {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}
.customize-group label {
  font-size: 0.875rem;
  font-weight: 500;
}

/* Common Elements: Buttons, Inputs */
.form-input,
.form-select {
  width: 100%;
  padding: 0.75rem;
  background-color: var(--surface-color);
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  transition: border-color 0.2s, box-shadow 0.2s;
  font-size: 1rem;
  color: var(--text-color);
}
.form-input:focus,
.form-select:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px var(--primary-color);
}
.form-input-sm {
  padding: 0.5rem;
  font-size: 0.875rem;
}

.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 0.5rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}
.btn i {
  font-size: 1em;
}
.btn-primary {
  background-color: var(--primary-color);
  color: white;
  box-shadow: 0 4px 6px -1px var(--shadow-color),
    0 2px 4px -2px var(--shadow-color);
}
.dark .btn-primary {
  color: #fff;
}
.btn-primary:hover {
  background-color: var(--primary-hover-color);
  transform: translateY(-2px);
  box-shadow: 0 10px 15px -3px var(--shadow-color),
    0 4px 6px -4px var(--shadow-color);
}
.btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: translateY(0);
  box-shadow: none;
}
.btn-secondary {
  background-color: var(--secondary-surface-color);
  color: var(--text-color);
}
.btn-secondary:hover {
  background-color: var(--secondary-surface-hover-color);
}
.btn-green {
  background-color: var(--success-color);
  color: white;
}
.btn-green:hover {
  background-color: var(--success-hover-color);
}
.btn-red {
  background-color: var(--danger-color);
  color: white;
}
.btn-red:hover {
  background-color: var(--danger-hover-color);
}
.btn-teal {
  background-color: var(--teal-color);
  color: white;
}
.btn-teal:hover {
  background-color: var(--teal-hover-color);
}
.btn-sm {
  font-size: 0.875rem;
  padding: 0.375rem 0.75rem;
  border-radius: 0.375rem;
}
.btn-subtle {
  background-color: var(--primary-subtle-bg);
  color: var(--primary-color);
  font-weight: 600;
}
.btn-icon {
  padding: 0.25rem;
  border-radius: 9999px;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--danger-color);
  transition: background-color 0.2s;
  width: 28px;
  height: 28px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.btn-icon:hover {
  background-color: var(--danger-subtle-bg);
}
.btn-icon i {
  font-size: 0.875rem;
}
.hidden {
  display: none !important;
}

.btn-add {
  width: 100%;
  margin-top: 0.5rem;
  padding: 0.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--primary-color);
  border: 2px dashed var(--border-color);
  border-radius: 0.75rem;
  background: none;
  cursor: pointer;
  transition: all 0.2s ease-in-out;
}
.btn-add:hover {
  background-color: var(--surface-hover-color);
  border-color: var(--primary-color);
}
.action-buttons {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
  margin-top: 2rem;
}

/* Notification */
#notification {
  position: fixed;
  top: 1.25rem;
  right: 1.25rem;
  color: white;
  padding: 0.75rem 1.25rem;
  border-radius: 0.5rem;
  box-shadow: 0 10px 15px -3px var(--shadow-color);
  transform: translateX(120%);
  transition: transform 0.5s;
  z-index: 50;
}

/* Utility & Animations */
.custom-scrollbar::-webkit-scrollbar {
  width: 8px;
}
.custom-scrollbar::-webkit-scrollbar-track {
  background: transparent;
}
.custom-scrollbar::-webkit-scrollbar-thumb {
  background-color: #9ca3af;
  border-radius: 10px;
  border: 2px solid transparent;
  background-clip: content-box;
}
.dark .custom-scrollbar::-webkit-scrollbar-thumb {
  background-color: #4b5563;
}

/* Responsive Design */
@media (min-width: 640px) {
  h1 {
    font-size: 1.875rem;
  }
  main {
    padding: 2rem;
  }
  header {
    margin-bottom: 2rem;
  }
  #chartTypeGrid {
    grid-template-columns: repeat(3, 1fr);
  }
  #customize-panel {
    grid-template-columns: repeat(2, 1fr);
  }
}
@media (min-width: 768px) {
  .data-entry-header {
    flex-direction: row;
    align-items: center;
  }
}
@media (min-width: 1024px) {
  #data-entry-area {
    grid-template-columns: repeat(2, 1fr);
  }
  .chart-display-grid {
    grid-template-columns: 2fr 1fr;
  }
}