/* ─── DESIGN TOKENS ─────────────────────────────── */
:root {
  --bg:        #0a0a0f;
  --surface:   #111118;
  --surface2:  #1a1a25;
  --border:    #2a2a3a;
  --accent:    #6ee7b7;
  --accent2:   #818cf8;
  --accent3:   #fb923c;
  --text:      #e2e8f0;
  --muted:     #64748b;
  --danger:    #f87171;

  --font-head: 'Syne', sans-serif;
  --font-body: 'DM Sans', sans-serif;
  --font-mono: 'DM Mono', monospace;

  --radius-sm: 8px;
  --radius:    14px;
  --radius-lg: 22px;

  --shadow: 0 4px 24px rgba(0,0,0,0.4);
  --glow:   0 0 32px rgba(110,231,183,0.08);
}

/* ─── RESET & BASE ──────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* ─── NOISE TEXTURE ─────────────────────────────── */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.03'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: 0;
  opacity: 0.4;
}

/* ─── HEADER ────────────────────────────────────── */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10,10,15,0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  padding: 0 clamp(16px, 4vw, 48px);
}

.header-inner {
  max-width: 1400px;
  margin: 0 auto;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 1.1rem;
  color: var(--text);
  letter-spacing: -0.5px;
}

.logo-dot { color: var(--accent); }

nav { display: flex; gap: 24px; }
nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.875rem;
  transition: color 0.2s;
}
nav a:hover { color: var(--accent); }

/* ─── HERO ──────────────────────────────────────── */
.hero {
  text-align: center;
  padding: clamp(48px, 8vw, 96px) clamp(16px,4vw,48px) 40px;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(110,231,183,0.08);
  border: 1px solid rgba(110,231,183,0.2);
  border-radius: 999px;
  padding: 4px 14px;
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--accent);
  margin-bottom: 20px;
  letter-spacing: 0.05em;
}

.hero h1 {
  font-family: var(--font-head);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -1.5px;
  margin-bottom: 16px;
}

.hero h1 em {
  font-style: normal;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent2) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  max-width: 580px;
  margin: 0 auto 32px;
  color: var(--muted);
  font-size: 1rem;
}

/* ─── CHART TYPE SELECTOR ───────────────────────── */
.chart-type-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin-bottom: 40px;
}

.chart-type-btn {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--muted);
  padding: 8px 14px;
  font-family: var(--font-body);
  font-size: 0.8rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all 0.2s;
  white-space: nowrap;
}

.chart-type-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.chart-type-btn.active {
  background: rgba(110,231,183,0.1);
  border-color: var(--accent);
  color: var(--accent);
}

.chart-type-btn .icon { font-size: 1rem; }

/* ─── MAIN LAYOUT ───────────────────────────────── */
.app-layout {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 clamp(16px, 4vw, 48px) 80px;
  display: grid;
  grid-template-columns: 380px 1fr;
  gap: 24px;
  position: relative;
  z-index: 1;
}

@media (max-width: 960px) {
  .app-layout { grid-template-columns: 1fr; }
}

/* ─── PANEL ─────────────────────────────────────── */
.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.panel-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 10px;
}

.panel-header h2 {
  font-family: var(--font-head);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

.panel-icon {
  width: 28px;
  height: 28px;
  border-radius: 6px;
  background: rgba(110,231,183,0.1);
  display: grid;
  place-items: center;
  font-size: 0.9rem;
}

.panel-body { padding: 20px; }

/* ─── FORM ELEMENTS ─────────────────────────────── */
.form-group { margin-bottom: 16px; }

.form-group label {
  display: block;
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--muted);
  margin-bottom: 6px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  padding: 9px 12px;
  transition: border-color 0.2s, box-shadow 0.2s;
  outline: none;
  appearance: none;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(110,231,183,0.1);
}

.form-group textarea {
  resize: vertical;
  min-height: 70px;
  line-height: 1.5;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

/* ─── DATASET MANAGER ───────────────────────────── */
.dataset-card {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 14px;
  margin-bottom: 12px;
  position: relative;
}

.dataset-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
}

.dataset-label-row {
  display: flex;
  align-items: center;
  gap: 8px;
}

.color-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  flex-shrink: 0;
}

.dataset-name {
  font-size: 0.8rem;
  font-family: var(--font-mono);
  color: var(--text);
  font-weight: 500;
}

.btn-icon {
  background: none;
  border: none;
  color: var(--muted);
  cursor: pointer;
  padding: 4px;
  border-radius: 4px;
  font-size: 0.85rem;
  line-height: 1;
  transition: color 0.2s, background 0.2s;
}

.btn-icon:hover { color: var(--danger); background: rgba(248,113,113,0.1); }

.color-picker-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 8px;
}

input[type="color"] {
  width: 32px !important;
  height: 32px !important;
  padding: 2px !important;
  border-radius: 6px !important;
  cursor: pointer;
}

/* ─── TABS ──────────────────────────────────────── */
.tabs {
  display: flex;
  gap: 4px;
  padding: 4px;
  background: var(--surface2);
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
}

.tab-btn {
  flex: 1;
  background: none;
  border: none;
  color: var(--muted);
  padding: 7px 10px;
  border-radius: 6px;
  font-family: var(--font-body);
  font-size: 0.78rem;
  cursor: pointer;
  transition: all 0.2s;
}

.tab-btn.active {
  background: var(--surface);
  color: var(--text);
  box-shadow: 0 1px 4px rgba(0,0,0,0.3);
}

.tab-panel { display: none; }
.tab-panel.active { display: block; }

/* ─── BUTTONS ───────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  white-space: nowrap;
}

.btn-primary {
  background: var(--accent);
  color: #0a0a0f;
  padding: 11px 20px;
  font-size: 0.875rem;
  width: 100%;
  justify-content: center;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.btn-primary:hover {
  background: #5dd4a7;
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(110,231,183,0.3);
}

.btn-secondary {
  background: var(--surface2);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 9px 14px;
  font-size: 0.8rem;
}

.btn-secondary:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.btn-add {
  background: rgba(129,140,248,0.08);
  border: 1px dashed rgba(129,140,248,0.3);
  color: var(--accent2);
  padding: 9px 14px;
  font-size: 0.8rem;
  width: 100%;
  justify-content: center;
  border-radius: var(--radius-sm);
  margin-top: 4px;
}

.btn-add:hover {
  background: rgba(129,140,248,0.14);
  border-color: var(--accent2);
}

.export-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-top: 12px;
}

.btn-export {
  background: var(--surface2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 10px;
  font-size: 0.78rem;
  font-family: var(--font-mono);
  justify-content: center;
  border-radius: var(--radius-sm);
}

.btn-export:hover {
  border-color: var(--accent3);
  color: var(--accent3);
  background: rgba(251,146,60,0.05);
}

/* ─── CHART PANEL ───────────────────────────────── */
.chart-panel {
  display: flex;
  flex-direction: column;
}

.chart-toolbar {
  padding: 12px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
}

.chart-title-input {
  background: none;
  border: none;
  color: var(--text);
  font-family: var(--font-head);
  font-size: 1rem;
  font-weight: 700;
  outline: none;
  flex: 1;
  min-width: 150px;
}

.chart-title-input::placeholder { color: var(--muted); }

.chart-area {
  flex: 1;
  padding: 24px;
  position: relative;
  min-height: 460px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.chart-empty {
  text-align: center;
  color: var(--muted);
}

.chart-empty .big-icon {
  font-size: 3.5rem;
  margin-bottom: 12px;
  opacity: 0.4;
}

.chart-empty p {
  font-size: 0.875rem;
}

#chartCanvas {
  width: 100% !important;
  height: 100% !important;
  position: absolute;
  inset: 24px;
}

/* ─── STATS BAR ─────────────────────────────────── */
.stats-bar {
  padding: 12px 20px;
  border-top: 1px solid var(--border);
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}

.stat-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.stat-label {
  font-size: 0.7rem;
  font-family: var(--font-mono);
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.stat-value {
  font-size: 0.9rem;
  font-family: var(--font-mono);
  font-weight: 500;
  color: var(--accent);
}

/* ─── RANGE SLIDER ──────────────────────────────── */
input[type="range"] {
  -webkit-appearance: none;
  width: 100%;
  height: 4px;
  background: var(--border);
  border-radius: 99px;
  outline: none;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
}

.range-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.range-val {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--accent);
  min-width: 28px;
  text-align: right;
}

/* ─── CHECKBOX ──────────────────────────────────── */
.check-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
}

.check-row input[type="checkbox"] {
  width: 15px;
  height: 15px;
  accent-color: var(--accent);
  cursor: pointer;
}

.check-row label {
  font-size: 0.8rem;
  color: var(--text);
  cursor: pointer;
  margin: 0;
  text-transform: none;
  letter-spacing: 0;
}

/* ─── SEO CONTENT ───────────────────────────────── */
.seo-section {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 clamp(16px, 4vw, 48px) 80px;
  position: relative;
  z-index: 1;
}

.seo-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
  margin: 40px 0;
}

.seo-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}

.seo-card h3 {
  font-family: var(--font-head);
  font-size: 1rem;
  margin-bottom: 10px;
  color: var(--text);
}

.seo-card p, .seo-card li {
  font-size: 0.875rem;
  color: var(--muted);
  line-height: 1.7;
}

.seo-card ul {
  padding-left: 16px;
}

.seo-card ul li { margin-bottom: 4px; }

.seo-divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 48px 0;
}

.faq-item {
  border-bottom: 1px solid var(--border);
  padding: 20px 0;
}

.faq-q {
  font-family: var(--font-head);
  font-size: 0.95rem;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text);
}

.faq-q::after { content: '+'; color: var(--accent); font-size: 1.2rem; }
.faq-item.open .faq-q::after { content: '−'; }

.faq-a {
  font-size: 0.875rem;
  color: var(--muted);
  margin-top: 10px;
  line-height: 1.7;
  display: none;
}

.faq-item.open .faq-a { display: block; }

.chart-type-showcase {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 12px;
  margin: 20px 0;
}

.showcase-card {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px 12px;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s;
}

.showcase-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.showcase-card .icon { font-size: 1.8rem; margin-bottom: 6px; }
.showcase-card .name { font-size: 0.75rem; color: var(--muted); font-family: var(--font-mono); }

/* ─── FOOTER ────────────────────────────────────── */
footer {
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 24px clamp(16px,4vw,48px);
  text-align: center;
  font-size: 0.8rem;
  color: var(--muted);
  position: relative;
  z-index: 1;
}

/* ─── TOAST ─────────────────────────────────────── */
.toast {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background: var(--surface2);
  border: 1px solid var(--accent);
  border-radius: var(--radius-sm);
  padding: 12px 18px;
  font-size: 0.85rem;
  font-family: var(--font-mono);
  color: var(--accent);
  z-index: 9999;
  transform: translateY(80px);
  opacity: 0;
  transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  pointer-events: none;
}

.toast.show { transform: translateY(0); opacity: 1; }

/* ─── RESPONSIVE FIXES ──────────────────────────── */
@media (max-width: 640px) {
  .form-row { grid-template-columns: 1fr; }
  .export-grid { grid-template-columns: 1fr 1fr; }
  .chart-area { min-height: 300px; }
}