/* Hintergrund-weg — eigene Palette: Foto-Tool Türkis #0891b2 + Schachbrett-Transparenz */
:root {
  --c-primary: #0891b2;
  --c-primary-d: #0e7490;
  --c-primary-l: #06b6d4;
  --c-accent: #14b8a6;
  --c-accent-d: #0d9488;

  --bg: #f1f5f7;
  --bg-grad-1: #e6f3f6;
  --bg-grad-2: #f4fbfc;
  --surface: #ffffff;
  --surface-2: #f7fafb;
  --text: #0f2c33;
  --text-soft: #436069;
  --border: #d4e3e7;
  --ring: #0891b2;
  --shadow: 0 6px 22px rgba(8, 80, 100, 0.10);

  --check-a: #cfd8dc;
  --check-b: #ffffff;
  --check-size: 14px;

  --radius: 14px;
  --radius-sm: 9px;
  --gap: 16px;
  --tap: 44px;
}

[data-theme="dark"] {
  --bg: #08171b;
  --bg-grad-1: #0a2228;
  --bg-grad-2: #06141a;
  --surface: #102a31;
  --surface-2: #0c2026;
  --text: #e6f4f7;
  --text-soft: #9fc3cc;
  --border: #1d4751;
  --ring: #22d3ee;
  --shadow: 0 6px 22px rgba(0, 0, 0, 0.45);

  --check-a: #1a3a42;
  --check-b: #224853;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
}

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background:
    radial-gradient(1100px 520px at 12% -8%, var(--bg-grad-1), transparent 60%),
    radial-gradient(900px 480px at 110% 8%, var(--bg-grad-2), transparent 55%),
    var(--bg);
  color: var(--text);
  min-height: 100vh;
  line-height: 1.5;
  -webkit-text-size-adjust: 100%;
  padding:
    env(safe-area-inset-top)
    env(safe-area-inset-right)
    env(safe-area-inset-bottom)
    env(safe-area-inset-left);
}

.sr-only {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0);
  white-space: nowrap; border: 0;
}

.hidden { display: none !important; }

.skip-link {
  position: absolute;
  left: -999px;
  top: 8px;
  background: var(--c-primary);
  color: #fff;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  z-index: 60;
}
.skip-link:focus { left: 8px; }

/* Header */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px clamp(12px, 4vw, 28px);
  position: sticky;
  top: 0;
  z-index: 30;
  background: color-mix(in srgb, var(--surface) 86%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.brand { display: flex; align-items: center; gap: 11px; min-width: 0; }
.brand-mark {
  display: inline-flex;
  filter: drop-shadow(0 3px 6px rgba(8, 80, 100, 0.28));
}
.brand-text { min-width: 0; }
.brand-text h1 {
  font-size: clamp(1.05rem, 3.6vw, 1.35rem);
  margin: 0;
  letter-spacing: -0.02em;
  line-height: 1.15;
}
.tagline {
  margin: 1px 0 0;
  font-size: 0.74rem;
  color: var(--text-soft);
}
.header-actions { display: flex; align-items: center; gap: 8px; }

/* Buttons */
.btn {
  font: inherit;
  font-weight: 600;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  padding: 11px 16px;
  min-height: var(--tap);
  cursor: pointer;
  transition: transform .12s ease, background .15s ease, box-shadow .15s ease, border-color .15s ease;
  color: var(--text);
  background: var(--surface-2);
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn:focus-visible {
  outline: 3px solid var(--ring);
  outline-offset: 2px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--c-primary-l), var(--c-primary-d));
  color: #fff;
  box-shadow: 0 4px 14px rgba(8, 145, 178, 0.3);
}
.btn-primary:hover { box-shadow: 0 6px 18px rgba(8, 145, 178, 0.42); }

.btn-accent {
  background: linear-gradient(135deg, var(--c-accent), var(--c-accent-d));
  color: #fff;
  box-shadow: 0 4px 14px rgba(20, 184, 166, 0.3);
}
.btn-accent:hover { box-shadow: 0 6px 18px rgba(20, 184, 166, 0.42); }

.btn-ghost {
  background: var(--surface-2);
  border-color: var(--border);
  color: var(--text);
}
.btn-ghost:hover { background: color-mix(in srgb, var(--c-primary) 8%, var(--surface-2)); }

.btn-small {
  padding: 8px 11px;
  min-height: 38px;
  font-size: 0.82rem;
}

.btn-icon {
  width: var(--tap);
  height: var(--tap);
  min-height: var(--tap);
  padding: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--surface-2);
  border-color: var(--border);
}
.theme-icon { font-size: 1.3rem; line-height: 1; }
.btn-icon[aria-pressed="true"] { color: var(--c-primary); }

/* Main + cards */
.app-main {
  max-width: 760px;
  margin: 0 auto;
  padding: clamp(14px, 4vw, 26px);
  display: flex;
  flex-direction: column;
  gap: var(--gap);
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: clamp(14px, 4vw, 22px);
  box-shadow: var(--shadow);
}
.card h2 {
  margin: 0 0 12px;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
}

.hint {
  margin: 0 0 8px;
  font-size: 0.92rem;
  color: var(--text-soft);
  overflow-wrap: anywhere;
}
.hint:last-child { margin-bottom: 0; }
.hint strong { color: var(--text); }
.hint-note {
  background: color-mix(in srgb, var(--c-primary) 9%, transparent);
  border: 1px solid color-mix(in srgb, var(--c-primary) 22%, transparent);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
}

/* Drop zone */
.drop-zone {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  text-align: center;
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: clamp(20px, 6vw, 36px) 16px;
  color: var(--text-soft);
  background: var(--surface-2);
  cursor: pointer;
  transition: border-color .15s ease, background .15s ease, color .15s ease;
}
.drop-zone:hover,
.drop-zone:focus-visible,
.drop-zone.drag {
  border-color: var(--c-primary);
  color: var(--c-primary);
  background: color-mix(in srgb, var(--c-primary) 8%, var(--surface-2));
  outline: none;
}
.drop-zone:focus-visible { outline: 3px solid var(--ring); outline-offset: 3px; }
.drop-icon { color: var(--c-primary); }
.drop-text { font-weight: 600; color: var(--text); overflow-wrap: anywhere; }
.drop-sub { font-size: 0.78rem; }

.loader-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 14px;
}
.loader-buttons .btn { flex: 1 1 160px; }

/* Canvas */
.canvas-wrap {
  position: relative;
  width: 100%;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  /* Schachbrett-Transparenz */
  background-color: var(--check-b);
  background-image:
    linear-gradient(45deg, var(--check-a) 25%, transparent 25%),
    linear-gradient(-45deg, var(--check-a) 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, var(--check-a) 75%),
    linear-gradient(-45deg, transparent 75%, var(--check-a) 75%);
  background-size: calc(var(--check-size) * 2) calc(var(--check-size) * 2);
  background-position:
    0 0,
    0 var(--check-size),
    var(--check-size) calc(-1 * var(--check-size)),
    calc(-1 * var(--check-size)) 0;
}
.preview-canvas {
  display: block;
  width: 100%;
  height: auto;
  cursor: crosshair;
  touch-action: none;
}
.canvas-wrap.pick-off .preview-canvas { cursor: default; }

.canvas-overlay-hint {
  position: absolute;
  left: 50%;
  bottom: 10px;
  transform: translateX(-50%);
  background: color-mix(in srgb, var(--c-primary-d) 90%, transparent);
  color: #fff;
  font-size: 0.78rem;
  font-weight: 600;
  padding: 6px 12px;
  border-radius: 999px;
  pointer-events: none;
  box-shadow: 0 3px 10px rgba(0,0,0,0.25);
}
.canvas-wrap.pick-off .canvas-overlay-hint { display: none; }

/* Controls */
.controls {
  margin-top: 16px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.control-row {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.control-row > label {
  font-weight: 600;
  font-size: 0.92rem;
}
.control-row output {
  font-variant-numeric: tabular-nums;
  color: var(--c-primary);
  font-weight: 700;
}

.color-line {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}
input[type="color"] {
  width: 52px;
  height: 40px;
  padding: 2px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  cursor: pointer;
}
input[type="color"]:disabled { opacity: 0.45; cursor: not-allowed; }
.color-readout {
  font-variant-numeric: tabular-nums;
  font-family: ui-monospace, "SF Mono", Menlo, monospace;
  font-size: 0.88rem;
  color: var(--text-soft);
  min-width: 72px;
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 8px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--c-primary), var(--c-primary-l));
  outline-offset: 4px;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: #fff;
  border: 3px solid var(--c-primary);
  box-shadow: 0 2px 6px rgba(0,0,0,0.25);
  cursor: pointer;
}
input[type="range"]::-moz-range-thumb {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #fff;
  border: 3px solid var(--c-primary);
  cursor: pointer;
}
input[type="range"]:focus-visible { outline: 3px solid var(--ring); }

.checkbox-row {
  flex-direction: row;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}
.check {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  font-weight: 600;
  font-size: 0.92rem;
}
.check input[type="checkbox"] {
  width: 22px;
  height: 22px;
  accent-color: var(--c-primary);
  cursor: pointer;
}

.button-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
}
.button-grid .btn { width: 100%; }

/* Footer */
.app-footer {
  text-align: center;
  color: var(--text-soft);
  font-size: 0.8rem;
  padding: 4px 0 10px;
}
.app-footer p { margin: 0; overflow-wrap: anywhere; }

/* Toasts */
.toast-wrap {
  position: fixed;
  left: 50%;
  bottom: calc(16px + env(safe-area-inset-bottom));
  transform: translateX(-50%);
  z-index: 70;
  display: flex;
  flex-direction: column;
  gap: 8px;
  width: min(420px, calc(100vw - 24px));
  pointer-events: none;
}
.toast {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  border-left: 4px solid var(--c-primary);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  box-shadow: var(--shadow);
  font-size: 0.9rem;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity .22s ease, transform .22s ease;
  overflow-wrap: anywhere;
}
.toast.show { opacity: 1; transform: translateY(0); }
.toast.ok { border-left-color: var(--c-accent); }
.toast.err { border-left-color: #e05656; }

/* Modal */
.modal-root {
  position: fixed;
  inset: 0;
  z-index: 80;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 18px;
}
.modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(6, 20, 24, 0.55);
  backdrop-filter: blur(3px);
}
.modal-box {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 22px;
  width: min(440px, 100%);
  z-index: 1;
}
.modal-title { margin: 0 0 8px; font-size: 1.1rem; }
.modal-body { margin: 0 0 18px; color: var(--text-soft); overflow-wrap: anywhere; }
.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  flex-wrap: wrap;
}

@media (max-width: 420px) {
  .button-grid { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
  }
}