:root {
  --blackboard: #176b52;
  --blackboard-deep: #0b4737;
  --blackboard-light: #2b8066;
  --chalk: #f4ebcf;
  --chalk-muted: #c8d8cf;
  --paper: #f8f0dc;
  --field-ink: #24332e;
  --pdf-red: #d9423a;
  --pdf-red-dark: #a8272d;
  --border: rgba(238, 244, 224, 0.28);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--chalk);
  font-family: "Hiragino Mincho ProN", "Yu Mincho", serif;
  background:
    radial-gradient(circle at 12% 12%, rgba(255, 255, 255, 0.07), transparent 34%),
    radial-gradient(circle at 88% 82%, rgba(217, 66, 58, 0.12), transparent 30%),
    linear-gradient(145deg, var(--blackboard-light), var(--blackboard-deep));
  display: grid;
  place-items: center;
  padding: 24px;
}

.card {
  width: min(680px, 100%);
  min-width: 0;
  overflow: visible;
  background:
    linear-gradient(rgba(255, 255, 255, 0.025), rgba(255, 255, 255, 0.01)),
    var(--blackboard);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 24px;
  box-shadow: 0 18px 48px rgba(0, 15, 10, 0.38);
  animation: fadeIn 420ms ease-out;
}

h1 {
  margin: 0 0 12px;
  font-size: clamp(1.35rem, 2.8vw, 1.9rem);
  letter-spacing: 0.04em;
  color: var(--chalk);
  text-shadow: 0 1px 0 rgba(255, 255, 255, 0.08);
}

p {
  margin: 8px 0 20px;
  line-height: 1.7;
}

.grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

label {
  font-size: 0.95rem;
  opacity: 0.92;
  display: block;
  margin-bottom: 6px;
}

label.option {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0;
  cursor: pointer;
}

.tooltip {
  position: relative;
}

.tooltip-text {
  position: absolute;
  z-index: 10;
  left: 50%;
  bottom: calc(100% + 9px);
  width: max-content;
  max-width: min(290px, 75vw);
  padding: 8px 10px;
  border: 1px solid rgba(255, 255, 255, 0.28);
  border-radius: 7px;
  color: var(--field-ink);
  background: var(--paper);
  box-shadow: 0 5px 14px rgba(0, 20, 14, 0.32);
  font-family: sans-serif;
  font-size: 0.78rem;
  line-height: 1.45;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translate(-50%, 4px);
  transition: opacity 120ms ease, transform 120ms ease, visibility 120ms ease;
}

.tooltip-text::after {
  position: absolute;
  top: 100%;
  left: 50%;
  border: 6px solid transparent;
  border-top-color: var(--paper);
  content: "";
  transform: translateX(-50%);
}

.tooltip:hover .tooltip-text,
.tooltip:focus-within .tooltip-text {
  opacity: 1;
  visibility: visible;
  transform: translate(-50%, 0);
}

.tooltip:hover,
.tooltip:focus-within {
  z-index: 20;
}

fieldset {
  margin: 0;
  padding: 12px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: rgba(0, 0, 0, 0.08);
}

legend {
  padding: 0 6px;
  font-size: 0.95rem;
  color: var(--chalk-muted);
}

.radio-group {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
}

input[type="file"],
input[type="number"] {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--paper);
  color: var(--field-ink);
  font: inherit;
}

input[type="radio"],
input[type="checkbox"] {
  accent-color: var(--pdf-red);
}

.actions {
  margin-top: 8px;
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

button {
  border: 0;
  border-radius: 999px;
  padding: 10px 18px;
  font: inherit;
  cursor: pointer;
  transition: transform 140ms ease, background 140ms ease;
  color: var(--chalk);
  background: linear-gradient(135deg, var(--pdf-red), var(--pdf-red-dark));
  box-shadow: 0 4px 12px rgba(100, 8, 14, 0.28);
}

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

button:disabled {
  opacity: 0.5;
  cursor: default;
  transform: none;
}

input:disabled {
  cursor: default;
}

.status {
  min-height: 1.6em;
  margin-top: 10px;
  font-size: 0.95rem;
  font-weight: bold;
  color: var(--chalk-muted);
}

.preview-panel {
  width: 100%;
  min-width: 0;
  max-width: 100%;
  height: clamp(160px, 29vh, 280px);
  margin-top: 18px;
  padding: 0;
  overflow: auto;
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: 12px;
  background: #073b2e;
  display: flex;
  align-items: flex-start;
  justify-content: flex-start;
  contain: inline-size;
}

.preview-panel canvas {
  display: block;
  flex: 0 0 auto;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.22);
}

.preview-panel iframe {
  width: 100%;
  height: 100%;
  flex: 1 1 auto;
  border: 0;
  background: white;
}

.preview-placeholder {
  margin: auto;
  padding: 20px;
  color: var(--chalk-muted);
  font-family: sans-serif;
}

.copyright {
  margin: 14px 0 0;
  color: var(--chalk-muted);
  font-family: sans-serif;
  font-size: 0.7rem;
  line-height: 1.4;
  text-align: center;
  letter-spacing: 0.03em;
  opacity: 0.55;
}

.copyright span {
  display: block;
}

.app-version {
  margin-top: 2px;
  font-size: 0.62rem;
  letter-spacing: 0.02em;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(6px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}