/* ============================================================
   LUMIO DESIGN SYSTEM
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;500;600;700&family=Inter:wght@400;500;600;700&display=swap');

:root {
  /* Core Neutrals */
  --ink-900: #1F1B3A;
  --ink-700: #3A3655;
  --ink-400: #8A8A9E;
  --surface-0: #FFFFFF;
  --surface-50: #FBFBFE;
  --border: #E5E5EE;

  /* Brand Spectrum */
  --violet: #7C3AED;
  --indigo: #4F46E5;
  --cyan: #06B6D4;
  --teal: #14B8A6;
  --orange: #F97316;
  --magenta: #D946EF;
  --yellow: #FACC15;

  /* Pillars */
  --pillar-learn: var(--indigo);
  --pillar-design: var(--orange);
  --pillar-inspire: var(--magenta);
  --pillar-ai: var(--cyan);
  --pillar-success: var(--teal);

  /* Gradients */
  --gradient-primary: linear-gradient(90deg, #7C3AED 0%, #4F46E5 55%, #06B6D4 100%);
  --gradient-warm: linear-gradient(135deg, #F97316 0%, #D946EF 100%);
  --gradient-ai: linear-gradient(90deg, #06B6D4 0%, #7C3AED 100%);

  /* Pastels */
  --pastel-lavender: #F2EEFB;
  --pastel-cyan: #E6FAFB;
  --pastel-pink: #FDEEF6;
  --pastel-peach: #FFF3EA;

  /* Radius */
  --r-sm: 8px;
  --r-md: 12px;
  --r-lg: 20px;
  --r-xl: 28px;
  --r-pill: 999px;

  /* Shadows */
  --shadow-soft: 0 8px 24px rgba(31, 27, 58, 0.06);
  --shadow-md: 0 12px 32px rgba(31, 27, 58, 0.10);
  --shadow-lift: 0 16px 40px rgba(124, 58, 237, 0.18);

  /* Type */
  --font-display: 'Poppins', sans-serif;
  --font-body: 'Inter', sans-serif;

  /* Premium gradients */
  --gradient-aurora: linear-gradient(120deg, #7C3AED 0%, #4F46E5 30%, #06B6D4 65%, #14B8A6 100%);
  --gradient-sunset: linear-gradient(120deg, #F97316 0%, #D946EF 60%, #7C3AED 100%);
  --gradient-mesh: radial-gradient(at 15% 20%, rgba(124,58,237,0.35) 0px, transparent 50%),
                   radial-gradient(at 85% 10%, rgba(6,182,212,0.30) 0px, transparent 50%),
                   radial-gradient(at 70% 80%, rgba(217,70,239,0.25) 0px, transparent 50%),
                   radial-gradient(at 10% 90%, rgba(20,184,166,0.25) 0px, transparent 50%);

  /* Glass */
  --glass-bg: rgba(255,255,255,0.55);
  --glass-border: rgba(255,255,255,0.45);
  --glass-blur: 18px;

  /* Theme Designer defaults (overridable per-course at runtime) */
  --theme-primary: var(--violet);
  --theme-secondary: var(--indigo);
  --theme-accent: var(--cyan);
  --theme-font-display: var(--font-display);
  --theme-font-body: var(--font-body);
  --theme-font-size: 16px;
  --theme-radius: var(--r-lg);
  --theme-button-style: var(--r-pill);
  --theme-bg-style: var(--surface-50);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  font-family: var(--theme-font-body, var(--font-body));
  font-size: var(--theme-font-size, 16px);
  color: var(--ink-700);
  background: var(--theme-bg-style, var(--surface-50));
  -webkit-font-smoothing: antialiased;
}

#app { min-height: 100vh; background: var(--theme-bg-style, var(--surface-50)); }

h1, h2, h3, h4 {
  font-family: var(--theme-font-display, var(--font-display));
  color: var(--ink-900);
  margin: 0;
}

p { margin: 0; line-height: 1.6; }

a { color: var(--theme-primary, var(--indigo)); text-decoration: none; }
a:hover { text-decoration: underline; }

img { max-width: 100%; display: block; }

button { font-family: var(--font-body); cursor: pointer; }

::selection { background: var(--pastel-lavender); }

/* ============================================================
   GRADIENT TEXT
   ============================================================ */
.gradient-text {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ============================================================
   BUTTONS
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--theme-font-body, var(--font-body));
  font-weight: 600;
  font-size: calc(var(--theme-font-size, 16px) - 2px);
  padding: 12px 22px;
  border-radius: var(--theme-button-style, var(--r-pill));
  border: none;
  cursor: pointer;
  transition: all 0.18s ease-out;
  white-space: nowrap;
}
.btn:active { transform: scale(0.98); }

.btn-primary {
  background: linear-gradient(90deg, var(--theme-primary, #7C3AED) 0%, var(--theme-secondary, #4F46E5) 55%, var(--theme-accent, #06B6D4) 100%);
  color: #fff;
  box-shadow: var(--shadow-soft);
}
.btn-primary:hover { box-shadow: var(--shadow-lift); filter: brightness(1.04); }

.btn-secondary {
  background: var(--surface-0);
  color: var(--ink-700);
  border: 1px solid var(--border);
}
.btn-secondary:hover { border-color: var(--theme-primary, var(--indigo)); color: var(--theme-primary, var(--indigo)); }

.btn-ghost {
  background: transparent;
  color: var(--ink-700);
  border: 1px solid transparent;
}
.btn-ghost:hover { background: var(--pastel-lavender); }

.btn-sm { padding: 8px 16px; font-size: calc(var(--theme-font-size, 16px) - 3px); }
.btn-lg { padding: 14px 30px; font-size: calc(var(--theme-font-size, 16px) - 1px); border-radius: var(--theme-radius, var(--r-lg)); }

.btn-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--r-md);
  border: 1px solid var(--border);
  background: var(--surface-0);
  color: var(--ink-400);
  transition: all 0.15s ease-out;
}
.btn-icon:hover { color: var(--indigo); border-color: var(--indigo); background: var(--pastel-lavender); }
.btn-icon.danger:hover { color: #E5484D; border-color: #E5484D; background: #FEECEC; }

.content-menu-btn:hover { color: var(--indigo); background: var(--pastel-lavender); }
.content-title-edit:focus { background: var(--pastel-lavender); box-shadow: 0 0 0 2px var(--indigo); }
.content-card.dragging { opacity: 0.5; }

/* ============================================================
   FORM ELEMENTS
   ============================================================ */
.field { display: flex; flex-direction: column; gap: 6px; margin-bottom: 18px; }
.field label { font-size: 13px; font-weight: 600; color: var(--ink-700); }
.field .hint { font-size: 12px; color: var(--ink-400); font-weight: 400; }

.input, .textarea, select.input {
  font-family: var(--font-body);
  font-size: 14px;
  padding: 12px 14px;
  border-radius: var(--r-md);
  border: 1px solid var(--border);
  background: var(--surface-0);
  color: var(--ink-900);
  outline: none;
  transition: border-color 0.15s, box-shadow 0.15s;
  width: 100%;
}
.input:focus, .textarea:focus, select.input:focus {
  border-color: var(--indigo);
  box-shadow: 0 0 0 4px rgba(79, 70, 229, 0.10);
}
.textarea { resize: vertical; min-height: 90px; font-family: var(--font-body); }

.input-icon-wrap { position: relative; }
.input-icon-wrap .input { padding-left: 40px; }
.input-icon-wrap .icon {
  position: absolute; left: 13px; top: 50%; transform: translateY(-50%);
  color: var(--ink-400); font-size: 16px; pointer-events: none;
}

/* ============================================================
   CARDS
   ============================================================ */
.card {
  background: var(--surface-0);
  border-radius: var(--theme-radius, var(--r-lg));
  box-shadow: var(--shadow-soft);
  border: 1px solid var(--border);
}

.card-pad { padding: 24px; }

/* ============================================================
   PILLS / BADGES
   ============================================================ */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: var(--r-pill);
  font-size: 12px;
  font-weight: 600;
}
.pill-indigo { background: rgba(79,70,229,0.10); color: var(--indigo); }
.pill-orange { background: rgba(249,115,22,0.12); color: var(--orange); }
.pill-teal { background: rgba(20,184,166,0.12); color: var(--teal); }
.pill-magenta { background: rgba(217,70,239,0.10); color: var(--magenta); }
.pill-cyan { background: rgba(6,182,212,0.12); color: var(--cyan); }
.pill-grey { background: var(--pastel-lavender); color: var(--ink-400); }

/* ============================================================
   APP SHELL / SIDEBAR
   ============================================================ */
.app-shell { display: flex; min-height: 100vh; }

.app-sidebar {
  width: 240px;
  flex-shrink: 0;
  background: var(--surface-0);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: 20px 14px;
  gap: 4px;
}

.sidebar-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px 20px 10px;
  cursor: pointer;
}
.sidebar-logo img { width: 34px; height: 34px; border-radius: 8px; }
.sidebar-logo span {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 18px;
  color: var(--ink-900);
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 12px;
  border-radius: var(--r-md);
  color: var(--ink-700);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
  border-left: 3px solid transparent;
}
.nav-item .ic { font-size: 18px; width: 20px; text-align: center; }
.nav-item:hover { background: var(--pastel-lavender); }
.nav-item.active {
  background: var(--pastel-lavender);
  color: var(--theme-primary, var(--indigo));
  font-weight: 600;
  border-left: 3px solid var(--theme-primary, var(--indigo));
}
.nav-section-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink-400);
  font-weight: 700;
  margin: 18px 12px 6px;
}

.app-main {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

.app-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 32px;
  border-bottom: 1px solid var(--border);
  background: var(--surface-0);
  gap: 16px;
}

.app-content {
  flex: 1;
  padding: 32px;
  position: relative;
  overflow-y: auto;
}

/* ambient blobs */
.ambient-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
  z-index: 0;
  pointer-events: none;
}
.blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(60px);
  opacity: 0.55;
}

/* ============================================================
   AVATAR
   ============================================================ */
.avatar {
  width: 36px; height: 36px; border-radius: 50%;
  background: var(--gradient-primary);
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-weight: 700; font-size: 14px;
  flex-shrink: 0;
}

/* ============================================================
   TABS
   ============================================================ */
.tabs { display: flex; gap: 4px; border-bottom: 1px solid var(--border); }
.tab {
  padding: 10px 18px;
  font-size: 14px;
  font-weight: 600;
  color: var(--ink-400);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
}
.tab.active { color: var(--theme-primary, var(--indigo)); border-bottom: 2px solid var(--theme-primary, var(--indigo)); }

/* ============================================================
   AI ELEMENTS
   ============================================================ */
.ai-card {
  border-radius: var(--r-lg);
  border: 1px solid rgba(124,58,237,0.18);
  background: linear-gradient(135deg, rgba(124,58,237,0.06), rgba(6,182,212,0.06));
  padding: 18px 20px;
  display: flex;
  gap: 14px;
  align-items: flex-start;
}
.ai-spark {
  width: 32px; height: 32px; border-radius: 50%;
  background: var(--gradient-ai);
  flex-shrink: 0;
  display: flex; align-items: center; justify-content: center;
  font-size: 16px;
  animation: pulse-glow 2.4s ease-in-out infinite;
}
@keyframes pulse-glow {
  0%, 100% { box-shadow: 0 0 0 0 rgba(6,182,212,0.35); }
  50% { box-shadow: 0 0 0 8px rgba(6,182,212,0); }
}

/* ============================================================
   MODALS / OVERLAYS
   ============================================================ */
.overlay {
  position: fixed; inset: 0;
  background: rgba(31,27,58,0.35);
  backdrop-filter: blur(4px);
  display: flex; align-items: center; justify-content: center;
  z-index: 100;
  animation: fadeIn 0.2s ease-out;
}
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.modal {
  background: var(--surface-0);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-md);
  max-width: 92vw;
  max-height: 88vh;
  overflow-y: auto;
  animation: modalIn 0.25s cubic-bezier(.2,.8,.2,1);
}
@keyframes modalIn {
  from { opacity: 0; transform: translateY(16px) scale(0.98); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

/* ============================================================
   UTILITIES
   ============================================================ */
.flex { display: flex; }
.flex-col { display: flex; flex-direction: column; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.justify-between { justify-content: space-between; }
.justify-end { justify-content: flex-end; }
.justify-center { justify-content: center; }
.gap-4 { gap: 4px; }
.gap-8 { gap: 8px; }
.gap-12 { gap: 12px; }
.gap-16 { gap: 16px; }
.gap-24 { gap: 24px; }
.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mb-8 { margin-bottom: 8px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }
.text-muted { color: var(--ink-400); }
.text-sm { font-size: 13px; }
.text-center { text-align: center; }
.w-full { width: 100%; }
.fade-in { animation: fadeInUp 0.35s ease-out; }
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* spinner / shimmer for AI generation */
.shimmer {
  background: linear-gradient(90deg, var(--pastel-lavender) 25%, var(--pastel-cyan) 50%, var(--pastel-lavender) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.4s linear infinite;
}
@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ============================================================
   GLASSMORPHISM
   ============================================================ */
.glass {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
}
.glass-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  border-radius: var(--r-xl);
  box-shadow: var(--shadow-md);
}

/* Mesh / aurora backdrops */
.mesh-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  background: var(--gradient-mesh);
  opacity: 0.9;
}
.aurora-panel {
  background: var(--gradient-aurora);
  background-size: 200% 200%;
  animation: auroraShift 18s ease-in-out infinite;
}
@keyframes auroraShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

/* ============================================================
   PREMIUM / INTERACTIVE CARDS
   ============================================================ */
.card-premium {
  background: var(--surface-0);
  border-radius: var(--r-xl);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-soft);
  transition: transform 0.22s cubic-bezier(.2,.8,.2,1), box-shadow 0.22s ease-out, border-color 0.22s ease-out;
}
.card-premium:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lift);
  border-color: rgba(124,58,237,0.25);
}
.card-interactive {
  cursor: pointer;
}

/* Big choice cards (Welcome screen, Create New, Help Me Decide) */
.choice-card {
  position: relative;
  border-radius: var(--r-xl);
  border: 1px solid var(--border);
  background: var(--surface-0);
  padding: 28px 24px;
  text-align: left;
  cursor: pointer;
  overflow: hidden;
  transition: transform 0.22s cubic-bezier(.2,.8,.2,1), box-shadow 0.22s ease-out, border-color 0.22s ease-out;
}
.choice-card:hover {
  transform: translateY(-6px) scale(1.01);
  box-shadow: var(--shadow-lift);
  border-color: transparent;
}
.choice-card .choice-glow {
  position: absolute; inset: -40% -40% auto auto; width: 220px; height: 220px;
  border-radius: 50%; filter: blur(50px); opacity: 0.35; z-index: 0;
  transition: opacity 0.22s ease-out;
}
.choice-card:hover .choice-glow { opacity: 0.55; }
.choice-card > * { position: relative; z-index: 1; }
.choice-icon {
  width: 56px; height: 56px; border-radius: var(--r-lg);
  display: flex; align-items: center; justify-content: center;
  font-size: 26px; margin-bottom: 16px; color: #fff;
  box-shadow: var(--shadow-soft);
}

/* ============================================================
   THEME DESIGNER
   ============================================================ */
.swatch-wheel {
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  gap: 8px;
}
.swatch {
  width: 100%; aspect-ratio: 1; border-radius: 50%; cursor: pointer;
  border: 2px solid transparent; transition: transform .12s, border-color .12s;
}
.swatch:hover { transform: scale(1.12); }
.swatch.selected { border-color: var(--ink-900); transform: scale(1.12); }

.color-input-row {
  display: flex; align-items: center; gap: 12px;
}
.color-input-row input[type="color"] {
  width: 44px; height: 44px; border-radius: var(--r-md); border: 1px solid var(--border);
  padding: 2px; cursor: pointer; background: var(--surface-0);
}

.theme-preview-card {
  border-radius: var(--theme-radius, var(--r-lg));
  overflow: hidden;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-soft);
  font-family: var(--theme-font-body, var(--font-body));
}
.theme-preview-card .tp-hero {
  padding: 28px;
  background: linear-gradient(135deg, var(--theme-primary, var(--violet)), var(--theme-secondary, var(--indigo)));
  color: #fff;
}
.theme-preview-card .tp-hero h3 {
  font-family: var(--theme-font-display, var(--font-display));
  color: #fff;
  font-size: calc(var(--theme-font-size, 16px) + 8px);
}
.theme-preview-card .tp-body { padding: 20px; background: var(--surface-0); }
.theme-preview-card .tp-btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 20px; font-weight: 600; font-size: 13px;
  border-radius: var(--theme-button-style, var(--r-pill));
  background: var(--theme-accent, var(--cyan)); color: #fff; margin-top: 12px;
}

/* ============================================================
   LANDING PAGE LAYOUTS
   ============================================================ */
.layout-thumb {
  border-radius: var(--r-md);
  border: 2px solid var(--border);
  cursor: pointer;
  overflow: hidden;
  transition: border-color .15s, transform .15s;
  background: var(--surface-0);
}
.layout-thumb:hover { transform: translateY(-2px); }
.layout-thumb.selected { border-color: var(--indigo); }
.layout-thumb .lt-frame { padding: 10px; height: 70px; display: flex; gap: 4px; }
.lt-block { background: var(--pastel-lavender); border-radius: 4px; }

/* ============================================================
   ACCORDION / EXPANDABLE BLOCKS (no layout jump)
   ============================================================ */
.acc-item { border-radius: var(--r-md); overflow: hidden; margin-bottom: 8px; border: 1px solid var(--border); }
.acc-header {
  display: flex; justify-content: space-between; align-items: center;
  padding: 12px 16px; font-weight: 600; font-size: 13px; cursor: pointer;
  background: var(--surface-0); transition: background .12s;
}
.acc-header:hover { background: var(--pastel-lavender); }
.acc-body {
  display: grid; grid-template-rows: 0fr; transition: grid-template-rows .25s ease-out;
}
.acc-body.open { grid-template-rows: 1fr; }
.acc-body > div { overflow: hidden; }
.acc-body-inner { padding: 0 16px; }
.acc-body.open .acc-body-inner { padding: 12px 16px; }

/* ============================================================
   PROPERTIES PANEL
   ============================================================ */
.prop-section { margin-bottom: 18px; }
.prop-section-title {
  font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em;
  color: var(--ink-400); margin-bottom: 10px;
}
.prop-row { display: flex; gap: 8px; }
.seg-control {
  display: flex; border: 1px solid var(--border); border-radius: var(--r-md); overflow: hidden; flex: 1;
}
.seg-control button {
  flex: 1; border: none; background: var(--surface-0); padding: 8px 6px; font-size: 12px;
  font-weight: 600; color: var(--ink-700); cursor: pointer; transition: all .12s;
  border-right: 1px solid var(--border);
}
.seg-control button:last-child { border-right: none; }
.seg-control button.active { background: var(--gradient-primary); color: #fff; }

/* toast */
.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--ink-900);
  color: #fff;
  padding: 12px 22px;
  border-radius: var(--r-pill);
  font-size: 13px;
  font-weight: 500;
  box-shadow: var(--shadow-md);
  z-index: 200;
  display: flex; align-items: center; gap: 10px;
  animation: fadeInUp 0.3s ease-out;
}