:root {
  --bg: #0f172a;
  --panel: #111827;
  --panel-2: #1f2937;
  --muted: #94a3b8;
  --text: #e5eefb;
  --accent: #7dd3fc;
  --accent-strong: #38bdf8;
  --highlight: #f9d77e;
  --success: #a7f3d0;
  --danger: #fca5a5;
  --paper: #f5f1e6;
  --border: rgba(148, 163, 184, 0.2);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  min-height: 100svh;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: radial-gradient(circle at top, #1e293b 0%, var(--bg) 55%);
  color: var(--text);
}

.page-shell {
  max-width: 1200px;
  margin: 0 auto;
  padding: 32px 20px max(52px, env(safe-area-inset-bottom));
}

.topbar {
  margin-bottom: 24px;
}

.eyebrow {
  margin: 0 0 8px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.75rem;
  color: var(--accent);
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 3rem);
}

.app-card {
  background: rgba(17, 24, 39, 0.88);
  border: 1px solid var(--border);
  border-radius: 24px;
  box-shadow: 0 30px 80px rgba(15, 23, 42, 0.45);
  padding: 24px;
}

.controls {
  display: grid;
  grid-template-columns: 1.2fr 0.9fr;
  gap: 16px;
  align-items: end;
  margin-bottom: 22px;
}

.file-picker,
.selector,
.slider-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 0.95rem;
  color: var(--muted);
}

.file-picker {
  position: relative;
  gap: 6px;
  min-height: 80px;
  justify-content: center;
  align-items: center;
  background: rgba(15, 23, 42, 0.7);
  border: 1.5px dashed rgba(125, 211, 252, 0.65);
  border-radius: 14px;
  padding: 16px;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease, transform 0.2s ease;
}

.file-picker:focus-within {
  outline: 2px solid var(--accent-strong);
  outline-offset: 3px;
}

.file-picker.dragover {
  background: rgba(56, 189, 248, 0.08);
  border-color: rgba(125, 211, 252, 1);
  transform: translateY(-1px);
}

.file-picker small {
  color: var(--accent);
  font-size: 0.76rem;
  letter-spacing: 0.04em;
}

.file-picker input,
.selector select,
.slider-group input {
  width: 100%;
  background: rgba(15, 23, 42, 0.7);
  border: 1px solid var(--border);
  border-radius: 12px;
  color: var(--text);
  padding: 12px 14px;
  font-size: 1rem;
}

.file-picker input {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: pointer;
}

.selector select {
  appearance: none;
}

.slider-row {
  display: flex;
  align-items: center;
  gap: 12px;
  background: rgba(15, 23, 42, 0.7);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 8px 12px;
}

.slider-row input {
  flex: 1;
  padding: 0;
  border: none;
  background: transparent;
}

.slider-row output {
  min-width: 52px;
  text-align: right;
  color: var(--text);
  font-weight: 700;
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

button {
  appearance: none;
  border: none;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  color: #022c22;
  font-weight: 700;
  padding: 12px 20px;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  box-shadow: 0 12px 18px rgba(56, 189, 248, 0.28);
  min-height: 48px;
}

button:hover {
  transform: translateY(-1px);
}

button.secondary {
  background: rgba(148, 163, 184, 0.14);
  border: 1px solid var(--border);
  color: var(--text);
  box-shadow: none;
}

.status {
  grid-column: 1 / -1;
  margin: 0;
  min-height: 24px;
  color: var(--success);
  font-size: 0.95rem;
  overflow-wrap: anywhere;
}

.open-image-link {
  grid-column: 1 / -1;
  width: fit-content;
  color: var(--accent);
  font-weight: 700;
  text-underline-offset: 0.2em;
}

.open-image-link[hidden] {
  display: none;
}

.preview-toggle {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 14px;
}

.preview-toggle button[aria-pressed="true"] {
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  border-color: transparent;
  color: #022c22;
  box-shadow: 0 12px 18px rgba(56, 189, 248, 0.28);
}

.preview-toggle button {
  min-width: 120px;
}

.preview-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
}

.panel {
  margin: 0;
  background: rgba(15, 23, 42, 0.7);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 16px;
}

.panel figcaption {
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 10px;
}

.drag-hint {
  display: inline-block;
  margin-top: 10px;
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
}

canvas {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 14px;
  background: linear-gradient(135deg, var(--paper), #ffffff);
  border: 1px solid rgba(15, 23, 42, 0.15);
  cursor: grab;
}

canvas:active {
  cursor: grabbing;
}

@media (max-width: 760px) {
  .page-shell {
    padding: 24px 16px max(32px, env(safe-area-inset-bottom));
  }

  .topbar {
    margin-bottom: 18px;
  }

  .controls,
  .preview-grid {
    grid-template-columns: 1fr;
  }

  .app-card {
    padding: 20px;
    border-radius: 20px;
  }

  .panel {
    padding: 12px;
    border-radius: 14px;
  }

  .preview-toggle button {
    flex: 1;
  }
}

@media (max-width: 480px) {
  .page-shell {
    padding: 18px 12px max(24px, env(safe-area-inset-bottom));
  }

  h1 {
    font-size: clamp(1.8rem, 8vw, 2.4rem);
  }

  .app-card {
    padding: 16px;
    border-radius: 18px;
  }

  .controls {
    gap: 14px;
    margin-bottom: 18px;
  }

  .button-row {
    display: grid;
    grid-template-columns: 1fr;
    gap: 10px;
  }

  .button-row button,
  .preview-toggle button {
    width: 100%;
  }

  .preview-toggle {
    margin-bottom: 12px;
  }

  .file-picker input,
  .selector select,
  .slider-group input {
    font-size: 16px;
  }

  .slider-row {
    gap: 10px;
    padding: 8px 10px;
  }

  .slider-row input {
    min-height: 32px;
    touch-action: pan-y;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}