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

:root {
  --bg-start: #0f0c29;
  --bg-mid:   #302b63;
  --bg-end:   #24243e;
  --panel-bg: rgba(255,255,255,0.07);
  --panel-border: rgba(255,255,255,0.15);
  --text-primary: #f0f0f0;
  --text-muted: #a0a0b8;
  --accent: #7c6bff;
  --accent-hover: #9a8dff;
  --slider-track: rgba(255,255,255,0.15);
  --slider-thumb: #7c6bff;
  --code-bg: rgba(0,0,0,0.35);
  --radius-panel: 20px;
  --radius-card: 16px;
  --transition: 0.18s ease;
}

html { scroll-behavior: smooth; }

/* ── Site Nav ─────────────────────────────────────────────── */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(15, 12, 41, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.nav-inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-size: 0.9rem;
  font-weight: 800;
  letter-spacing: 0.5px;
  color: var(--accent);
}

.nav-links {
  display: flex;
  gap: 6px;
}

.nav-link {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  text-decoration: none;
  padding: 6px 14px;
  border-radius: 99px;
  border: 1px solid transparent;
  transition: color var(--transition), background var(--transition), border-color var(--transition);
}

.nav-link:hover {
  color: var(--text-primary);
  background: rgba(255,255,255,0.07);
}

.nav-link.active {
  color: var(--text-primary);
  background: rgba(124,107,255,0.2);
  border-color: rgba(124,107,255,0.4);
}

body {
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  background: linear-gradient(135deg, var(--bg-start), var(--bg-mid), var(--bg-end));
  min-height: 100vh;
  color: var(--text-primary);
  line-height: 1.6;
}

/* ── Header ───────────────────────────────────────────────── */
header {
  text-align: center;
  padding: 52px 24px 36px;
}

header h1 {
  font-size: clamp(1.8rem, 5vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, #fff 30%, #b8adff);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 10px;
}

header p {
  color: var(--text-muted);
  font-size: 1.05rem;
  max-width: 520px;
  margin: 0 auto;
}

/* ── Main Layout ──────────────────────────────────────────── */
.app-shell {
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: 24px;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px 60px;
}

@media (max-width: 860px) {
  .app-shell { grid-template-columns: 1fr; }
}

/* ── Glass Panel ──────────────────────────────────────────── */
.glass-panel {
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius-panel);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  padding: 28px;
}

/* ── Controls Panel ───────────────────────────────────────── */
.controls-panel {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.panel-title {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 1.4px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 4px;
}

/* Presets */
.presets-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
}

.preset-btn {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: 10px;
  color: var(--text-primary);
  font-size: 0.72rem;
  font-weight: 600;
  padding: 9px 6px;
  cursor: pointer;
  transition: background var(--transition), border-color var(--transition), transform var(--transition);
  text-align: center;
  letter-spacing: 0.2px;
}

.preset-btn:hover {
  background: rgba(124,107,255,0.25);
  border-color: var(--accent);
  transform: translateY(-1px);
}

.preset-btn.active {
  background: rgba(124,107,255,0.35);
  border-color: var(--accent);
}

/* Sliders */
.control-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.control-label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.88rem;
  font-weight: 500;
}

.control-label span:first-child { color: var(--text-primary); }

.control-value {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--accent);
  min-width: 42px;
  text-align: right;
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 5px;
  border-radius: 99px;
  background: var(--slider-track);
  outline: none;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--slider-thumb);
  box-shadow: 0 0 0 3px rgba(124,107,255,0.3);
  transition: transform var(--transition), box-shadow var(--transition);
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.2);
  box-shadow: 0 0 0 5px rgba(124,107,255,0.4);
}

input[type="range"]::-moz-range-thumb {
  width: 18px;
  height: 18px;
  border: none;
  border-radius: 50%;
  background: var(--slider-thumb);
  box-shadow: 0 0 0 3px rgba(124,107,255,0.3);
  cursor: pointer;
}

/* Color Picker */
.color-picker-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

input[type="color"] {
  -webkit-appearance: none;
  appearance: none;
  width: 48px;
  height: 38px;
  border: 2px solid rgba(255,255,255,0.18);
  border-radius: 10px;
  background: none;
  cursor: pointer;
  padding: 2px;
  transition: border-color var(--transition);
}

input[type="color"]:hover { border-color: var(--accent); }
input[type="color"]::-webkit-color-swatch-wrapper { padding: 0; }
input[type="color"]::-webkit-color-swatch { border: none; border-radius: 7px; }

.color-hex {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-muted);
  font-family: monospace;
  background: rgba(0,0,0,0.2);
  padding: 5px 10px;
  border-radius: 8px;
  border: 1px solid rgba(255,255,255,0.1);
  flex: 1;
}

/* ── Right Column ─────────────────────────────────────────── */
.right-col {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

/* ── Preview Area ─────────────────────────────────────────── */
.preview-wrapper {
  border-radius: var(--radius-panel);
  overflow: hidden;
  position: relative;
  min-height: 320px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 24px;
}

.preview-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg,
    #f093fb 0%, #f5576c 20%,
    #4facfe 40%, #00f2fe 60%,
    #43e97b 80%, #38f9d7 100%);
  background-size: 200% 200%;
  animation: bgShift 8s ease infinite alternate;
}

@keyframes bgShift {
  0%   { background-position: 0% 50%; }
  100% { background-position: 100% 50%; }
}

.preview-bg::before,
.preview-bg::after {
  content: '';
  position: absolute;
  border-radius: 50%;
  filter: blur(40px);
  opacity: 0.5;
}

.preview-bg::before {
  width: 200px; height: 200px;
  background: rgba(255,100,200,0.6);
  top: -40px; left: 10%;
}

.preview-bg::after {
  width: 160px; height: 160px;
  background: rgba(60,200,255,0.7);
  bottom: -30px; right: 12%;
}

/* Glass preview card */
#glass-card {
  position: relative;
  z-index: 1;
  padding: 32px 36px;
  max-width: 340px;
  width: 100%;
  text-align: center;
  transition: all var(--transition);
}

.card-badge {
  display: inline-block;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  background: rgba(255,255,255,0.2);
  border-radius: 99px;
  padding: 4px 12px;
  margin-bottom: 14px;
  color: rgba(255,255,255,0.9);
}

.card-title {
  font-size: 1.45rem;
  font-weight: 800;
  margin-bottom: 10px;
  color: #fff;
  text-shadow: 0 1px 8px rgba(0,0,0,0.2);
}

.card-body {
  font-size: 0.88rem;
  color: rgba(255,255,255,0.82);
  margin-bottom: 22px;
  line-height: 1.65;
}

.card-btn {
  display: inline-block;
  background: rgba(255,255,255,0.25);
  border: 1px solid rgba(255,255,255,0.35);
  color: #fff;
  font-size: 0.84rem;
  font-weight: 700;
  padding: 10px 28px;
  border-radius: 99px;
  cursor: default;
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  transition: background var(--transition);
}

/* ── CSS Output ───────────────────────────────────────────── */
.output-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
}

.copy-btn {
  display: flex;
  align-items: center;
  gap: 7px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 10px;
  font-size: 0.82rem;
  font-weight: 700;
  padding: 9px 18px;
  cursor: pointer;
  transition: background var(--transition), transform var(--transition);
  letter-spacing: 0.3px;
}

.copy-btn:hover { background: var(--accent-hover); transform: translateY(-1px); }
.copy-btn:active { transform: translateY(0); }
.copy-btn.copied { background: #22c55e; }

.copy-btn svg { flex-shrink: 0; }

pre#css-output {
  background: var(--code-bg);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 14px;
  padding: 20px 22px;
  font-family: 'Cascadia Code', 'Fira Code', 'Consolas', monospace;
  font-size: 0.82rem;
  line-height: 1.75;
  color: #c9d1d9;
  overflow-x: auto;
  white-space: pre;
}

/* Syntax colors */
.tok-prop  { color: #79c0ff; }
.tok-colon { color: #c9d1d9; }
.tok-val   { color: #a5d6ff; }
.tok-rgba  { color: #ffa657; }
.tok-num   { color: #d2a8ff; }
.tok-semi  { color: #c9d1d9; }
.tok-unit  { color: #7ee787; }

/* ── Scrollbar ────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.15); border-radius: 99px; }

/* ── Footer ───────────────────────────────────────────────── */
footer {
  text-align: center;
  padding: 24px;
  color: var(--text-muted);
  font-size: 0.8rem;
  opacity: 0.6;
}