:root {
  color-scheme: light;
  --paper: #f7f3ec;
  --panel: #fffdf8;
  --ink: #22201c;
  --muted: #6f6a61;
  --line: #d8d0c3;
  --accent: #2f6f68;
  --accent-soft: #d9ebe7;
  --danger: #9c3f33;
  --shadow: 0 18px 45px rgba(42, 35, 24, 0.13);
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  overflow: hidden;
  background: var(--paper);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

button,
input,
label {
  font: inherit;
}

.app-shell {
  display: grid;
  grid-template-rows: auto 1fr;
  height: 100dvh;
  padding: max(12px, env(safe-area-inset-top)) max(12px, env(safe-area-inset-right))
    max(12px, env(safe-area-inset-bottom)) max(12px, env(safe-area-inset-left));
  gap: 12px;
}

.toolbar {
  display: flex;
  align-items: center;
  gap: 10px;
  overflow-x: auto;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 253, 248, 0.92);
  box-shadow: 0 8px 28px rgba(42, 35, 24, 0.08);
  -webkit-overflow-scrolling: touch;
}

.tool-group {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: 0 0 auto;
}

.file-group input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

.button,
.segment {
  min-height: 40px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fffaf1;
  color: var(--ink);
  padding: 0 13px;
  cursor: pointer;
  touch-action: manipulation;
}

.button:active,
.segment:active {
  transform: translateY(1px);
}

.segmented {
  gap: 0;
  padding: 3px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #efe8dc;
}

.segment {
  border: 0;
  background: transparent;
  min-width: 68px;
}

.segment.active {
  background: var(--accent);
  color: white;
  box-shadow: 0 2px 10px rgba(47, 111, 104, 0.25);
}

.danger {
  color: var(--danger);
}

.color-tool,
.range-tool {
  min-height: 40px;
  padding: 0 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fffaf1;
}

.color-tool label,
.range-tool label {
  color: var(--muted);
  font-size: 13px;
  white-space: nowrap;
}

input[type="color"] {
  width: 34px;
  height: 30px;
  padding: 0;
  border: 0;
  background: transparent;
}

input[type="range"] {
  width: 120px;
  accent-color: var(--accent);
}

.workspace {
  display: grid;
  min-height: 0;
  place-items: center;
}

.canvas-frame {
  position: relative;
  width: min(100%, calc((100dvh - 118px) * var(--canvas-ratio, 1.3333)));
  height: min(100%, calc((100dvw - 24px) / var(--canvas-ratio, 1.3333)));
  max-width: 100%;
  max-height: 100%;
  overflow: hidden;
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
  touch-action: none;
  user-select: none;
  -webkit-user-select: none;
}

.canvas-layer {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  touch-action: none;
  pointer-events: none;
}

.background-layer {
  z-index: 1;
}

.color-layer {
  z-index: 2;
}

.line-layer {
  z-index: 3;
}

.empty-state {
  position: absolute;
  inset: auto 16px 16px;
  z-index: 4;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 253, 248, 0.86);
  color: var(--muted);
  text-align: center;
  pointer-events: none;
}

.empty-state.hidden {
  display: none;
}

@media (orientation: portrait) {
  .toolbar {
    align-items: stretch;
  }

  .action-group {
    margin-left: auto;
  }
}

@media (max-width: 760px) {
  .app-shell {
    gap: 8px;
    padding: max(8px, env(safe-area-inset-top)) max(8px, env(safe-area-inset-right))
      max(8px, env(safe-area-inset-bottom)) max(8px, env(safe-area-inset-left));
  }

  .toolbar {
    padding: 8px;
    gap: 8px;
  }

  input[type="range"] {
    width: 96px;
  }

  .button,
  .segment {
    min-height: 38px;
    padding: 0 11px;
  }

  .canvas-frame {
    width: min(100%, calc((100dvh - 104px) * var(--canvas-ratio, 1.3333)));
    height: min(100%, calc((100dvw - 16px) / var(--canvas-ratio, 1.3333)));
  }
}