@import url('https://fonts.googleapis.com/css2?family=Google+Sans:wght@400;500;700&family=Google+Sans+Display:wght@400;700&display=swap');

*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  /* Material You — Dynamic Color (Blue seed #0062A1) */
  --md-primary:           #0062A1;
  --md-on-primary:        #FFFFFF;
  --md-primary-container: #CFE5FF;
  --md-on-primary-container: #001D35;

  --md-secondary:         #4F606E;
  --md-on-secondary:      #FFFFFF;
  --md-secondary-container: #D2E4F5;
  --md-on-secondary-container: #0B1D29;

  --md-tertiary:          #5A5B7E;
  --md-tertiary-container: #E1DFFF;

  --md-surface:           #F8FAFE;
  --md-surface-variant:   #DCE4EC;
  --md-on-surface:        #191C1E;
  --md-on-surface-variant:#41484D;

  --md-outline:           #71787D;
  --md-outline-variant:   #C1C8CD;

  --md-error:             #B3261E;
  --md-error-container:   #F9DEDC;

  --md-shadow: 0 1px 2px rgba(0,0,0,.08), 0 2px 6px rgba(0,0,0,.06);
  --md-shadow-lg: 0 4px 8px rgba(0,0,0,.10), 0 8px 24px rgba(0,0,0,.08);

  --radius-xs: 4px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 28px;
  --radius-full: 100px;

  --font: 'Google Sans', 'Segoe UI', system-ui, sans-serif;
  --font-display: 'Google Sans Display', 'Google Sans', sans-serif;

  /* Elevation tints (M3 spec: primary at opacity) */
  --el1: color-mix(in srgb, var(--md-primary) 5%, var(--md-surface));
  --el2: color-mix(in srgb, var(--md-primary) 8%, var(--md-surface));
  --el3: color-mix(in srgb, var(--md-primary) 11%, var(--md-surface));
}

/* ── Base ── */
body {
  font-family: var(--font);
  background: var(--md-surface);
  color: var(--md-on-surface);
  min-height: 100vh;
  line-height: 1.5;
}

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 20px 60px;
}

/* ── Header ── */
header {
  padding: 48px 0 36px;
  text-align: center;
}

.logo {
  width: 72px;
  height: 72px;
  border-radius: 24px;
  background: var(--md-primary-container);
  color: var(--md-on-primary-container);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  box-shadow: var(--md-shadow);
}

.logo img { width: 36px; height: 36px; }

h1 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 700;
  color: var(--md-on-surface);
  letter-spacing: -.01em;
  margin-bottom: 8px;
}

.subtitle {
  color: var(--md-on-surface-variant);
  font-size: 1rem;
  font-weight: 400;
}

/* ── Layout ── */
.app-container {
  display: grid;
  grid-template-columns: 400px 1fr;
  gap: 16px;
  align-items: start;
}

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

/* ── Card (M3 Surface Container) ── */
.card {
  background: var(--el1);
  border-radius: var(--radius-xl);
  padding: 28px;
  box-shadow: var(--md-shadow);
  border: 1px solid var(--md-outline-variant);
}

/* ── Panel title ── */
.panel-title {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--md-on-surface);
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 24px;
}

.panel-title .title-icon {
  width: 36px; height: 36px;
  border-radius: 50%;
  background: var(--md-secondary-container);
  color: var(--md-on-secondary-container);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.panel-title .title-icon svg { width: 18px; height: 18px; }

/* ── Form ── */
.form-group { margin-bottom: 24px; }

label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: .875rem;
  font-weight: 500;
  color: var(--md-on-surface-variant);
  margin-bottom: 8px;
}

label svg { width: 16px; height: 16px; }

.prompt-input {
  width: 100%;
  padding: 14px 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--md-outline);
  background: var(--md-surface);
  color: var(--md-on-surface);
  font-family: var(--font);
  font-size: .95rem;
  resize: vertical;
  transition: border-color .2s, box-shadow .2s;
  outline: none;
  min-height: 120px;
}

.prompt-input::placeholder { color: var(--md-outline); }

.prompt-input:focus {
  border-color: var(--md-primary);
  border-width: 2px;
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--md-primary) 12%, transparent);
}

/* ── Size chips ── */
.size-selection {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.size-option {
  flex: 1;
  min-width: 80px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 14px 10px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--md-outline-variant);
  background: var(--md-surface);
  color: var(--md-on-surface-variant);
  cursor: pointer;
  transition: all .2s;
  user-select: none;
}

.size-option svg { width: 22px; height: 22px; }

.size-option .size-label {
  font-size: .85rem;
  font-weight: 500;
}

.size-option .size-desc {
  font-size: .75rem;
  color: var(--md-outline);
}

.size-option:hover {
  background: var(--el2);
  border-color: var(--md-outline);
}

.size-option.active {
  background: var(--md-primary-container);
  border-color: var(--md-primary);
  color: var(--md-on-primary-container);
}

.size-option.active .size-desc { color: var(--md-on-primary-container); opacity: .7; }

/* ── Generate button (M3 Filled) ── */
.generate-btn {
  width: 100%;
  padding: 16px;
  border-radius: var(--radius-full);
  border: none;
  background: var(--md-primary);
  color: var(--md-on-primary);
  font-family: var(--font);
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: .02em;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  box-shadow: var(--md-shadow);
  transition: all .2s;
  position: relative;
  overflow: hidden;
}

.generate-btn svg { width: 20px; height: 20px; }

.generate-btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: white;
  opacity: 0;
  transition: opacity .15s;
}

.generate-btn:hover::before { opacity: .08; }
.generate-btn:active::before { opacity: .14; }

.generate-btn:disabled {
  background: color-mix(in srgb, var(--md-on-surface) 12%, transparent);
  color: color-mix(in srgb, var(--md-on-surface) 38%, transparent);
  box-shadow: none;
  cursor: not-allowed;
}

.generate-btn:disabled::before { display: none; }

/* Spinner on button */
.btn-spinner {
  width: 20px; height: 20px;
  border: 2.5px solid rgba(255,255,255,.3);
  border-top-color: white;
  border-radius: 50%;
  animation: spin .7s linear infinite;
  display: none;
}

.generate-btn.loading .btn-spinner { display: block; }
.generate-btn.loading .btn-icon { display: none; }

/* ── Result panel ── */
.image-container { display: flex; flex-direction: column; gap: 12px; }

.result-wrapper {
  position: relative;
  width: 100%;
  aspect-ratio: 1;
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: var(--md-surface-variant);
  border: 1px solid var(--md-outline-variant);
}

.result-wrapper.landscape { aspect-ratio: 4/3; }
.result-wrapper.portrait  { aspect-ratio: 3/4; }
.result-wrapper.square    { aspect-ratio: 1/1; }

.placeholder {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  color: var(--md-on-surface-variant);
  background: var(--el2);
  transition: opacity .3s;
}

.placeholder svg { width: 48px; height: 48px; opacity: .5; }

.placeholder-title {
  font-size: 1rem;
  font-weight: 500;
  opacity: .7;
}

.placeholder-sub {
  font-size: .85rem;
  opacity: .5;
}

/* Loading overlay */
.loading-overlay {
  position: absolute;
  inset: 0;
  background: color-mix(in srgb, var(--md-surface) 80%, transparent);
  backdrop-filter: blur(4px);
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  z-index: 20;
}

.loading-spinner {
  width: 48px; height: 48px;
  border: 3px solid var(--md-outline-variant);
  border-top-color: var(--md-primary);
  border-radius: 50%;
  animation: spin .8s linear infinite;
}

.loading-text {
  font-size: .9rem;
  font-weight: 500;
  color: var(--md-on-surface-variant);
}

#generated-iframe {
  width: 100%;
  height: 100%;
  border: none;
  display: block;
}

/* ── Action buttons (M3 Tonal) ── */
.image-actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.action-btn {
  flex: 1;
  min-width: 120px;
  padding: 12px 18px;
  border-radius: var(--radius-full);
  border: none;
  background: var(--md-secondary-container);
  color: var(--md-on-secondary-container);
  font-family: var(--font);
  font-size: .9rem;
  font-weight: 500;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: all .2s;
  position: relative;
  overflow: hidden;
}

.action-btn svg { width: 18px; height: 18px; flex-shrink: 0; }

.action-btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: currentColor;
  opacity: 0;
  transition: opacity .15s;
}

.action-btn:hover::before { opacity: .08; }
.action-btn:active::before { opacity: .14; }

/* ── Footer ── */
footer {
  text-align: center;
  padding: 40px 0 0;
  font-size: .85rem;
  color: var(--md-on-surface-variant);
  opacity: .6;
}

/* ── Animations ── */
@keyframes spin { to { transform: rotate(360deg); } }

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}

.card { animation: fadeIn .4s ease both; }
.card:nth-child(2) { animation-delay: .07s; }