:root {
  color-scheme: light dark;
  --background: #0f172a;
  --surface: rgba(15, 23, 42, 0.85);
  --text: #e2e8f0;
  --muted: #94a3b8;
  --accent: #38bdf8;
  --accent-strong: #0ea5e9;
  --border: rgba(148, 163, 184, 0.2);
  font-family: "Inter", "Hiragino Sans", "Yu Gothic", sans-serif;
}

body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(circle at top, rgba(56, 189, 248, 0.2), transparent 55%),
    var(--background);
  color: var(--text);
  display: flex;
  flex-direction: column;
}

a {
  color: inherit;
}

.app-header,
.app-footer {
  text-align: center;
  padding: 2rem 1rem;
}

.app-header h1 {
  margin-bottom: 0.5rem;
  font-size: clamp(1.8rem, 3vw, 2.4rem);
}

.lead {
  color: var(--muted);
  margin: 0 auto;
  max-width: 56rem;
  line-height: 1.6;
}

.app-main {
  flex: 1;
  width: min(960px, 92vw);
  margin: 0 auto;
  display: grid;
  gap: 1.5rem;
  padding-bottom: 3rem;
}

.card {
  background: var(--surface);
  backdrop-filter: blur(12px);
  border-radius: 1rem;
  padding: 2rem;
  border: 1px solid var(--border);
  box-shadow: 0 25px 60px rgba(15, 23, 42, 0.35);
}

.card h2 {
  margin-top: 0;
  font-size: 1.4rem;
}

.input-group {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  margin: 1rem 0;
}

.picker-control {
  align-items: stretch;
}

.picker-toggle {
  display: inline-flex;
  border-radius: 0.75rem;
  padding: 0.25rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border);
}

.picker-option {
  appearance: none;
  border: none;
  background: transparent;
  color: var(--muted);
  padding: 0.55rem 0.9rem;
  border-radius: 0.6rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
}

.picker-option.active,
.picker-option:focus-visible {
  background: rgba(56, 189, 248, 0.18);
  color: var(--text);
  outline: none;
}

.picker-control .button {
  flex: 1 1 auto;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.2rem;
  border-radius: 0.75rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}

.button input[type="file"] {
  display: none;
}

.button-primary {
  background: linear-gradient(120deg, var(--accent), var(--accent-strong));
  color: #0b1120;
  box-shadow: 0 12px 30px rgba(14, 165, 233, 0.3);
}

.button-secondary {
  background: rgba(255, 255, 255, 0.05);
  border-color: var(--border);
}

.button:hover {
  transform: translateY(-1px);
  box-shadow: 0 16px 40px rgba(15, 23, 42, 0.4);
}

.button:active {
  transform: translateY(0);
}

.input-separator {
  color: var(--muted);
}

.hint {
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 0.5rem;
}

.selected-files {
  margin-top: 1rem;
  border: 1px dashed var(--border);
  border-radius: 0.75rem;
  padding: 1rem;
  background: rgba(15, 23, 42, 0.4);
  max-height: 12rem;
  overflow-y: auto;
  font-family: "JetBrains Mono", "Menlo", "Consolas", monospace;
  font-size: 0.9rem;
  line-height: 1.5;
}

.selected-files.empty {
  color: var(--muted);
}

.settings-form {
  display: grid;
  gap: 1.5rem;
}

fieldset {
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  padding: 1rem;
  margin: 0;
}

legend {
  padding: 0 0.5rem;
}

.radio {
  display: flex;
  gap: 0.75rem;
  align-items: center;
  margin: 0.5rem 0;
}

.checkbox {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin: 0.5rem 0;
}

.toggle {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin: 0.5rem 0;
  font-weight: 600;
}

.toggle input[type="checkbox"] {
  width: 2.8rem;
  height: 1.4rem;
  appearance: none;
  background: rgba(148, 163, 184, 0.35);
  border-radius: 1rem;
  position: relative;
  cursor: pointer;
  transition: background 0.2s ease;
}

.toggle input[type="checkbox"]::after {
  content: "";
  position: absolute;
  top: 0.15rem;
  left: 0.15rem;
  width: 1.1rem;
  height: 1.1rem;
  border-radius: 50%;
  background: #0f172a;
  transition: transform 0.2s ease;
}

.toggle input[type="checkbox"]:checked {
  background: linear-gradient(120deg, var(--accent), var(--accent-strong));
}

.toggle input[type="checkbox"]:checked::after {
  transform: translateX(1.4rem);
}

.mode-settings {
  display: grid;
  gap: 0.5rem;
}

.mode-settings.hidden {
  display: none;
}

.mode-settings input[type="number"] {
  padding: 0.75rem;
  border-radius: 0.6rem;
  border: 1px solid var(--border);
  background: rgba(15, 23, 42, 0.4);
  color: var(--text);
}

.frame-rate-options {
  display: grid;
  gap: 0.5rem;
  margin-top: 0.5rem;
}

.frame-rate-options.hidden {
  display: none;
}

.frame-rate-presets {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.frame-rate-chip {
  appearance: none;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.4rem 0.85rem;
  background: rgba(15, 23, 42, 0.4);
  color: var(--muted);
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}

.frame-rate-chip.active,
.frame-rate-chip:focus-visible {
  background: rgba(56, 189, 248, 0.2);
  color: var(--text);
  border-color: rgba(56, 189, 248, 0.45);
  outline: none;
}

.frame-rate-chip:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

#results h3 {
  margin-top: 0;
}

.result-grid {
  display: grid;
  gap: 1.5rem;
}

@media (min-width: 720px) {
  .result-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.stats {
  display: grid;
  gap: 0.75rem;
}

.stats div {
  display: flex;
  justify-content: space-between;
  padding: 0.75rem 1rem;
  border-radius: 0.6rem;
  background: rgba(15, 23, 42, 0.4);
  border: 1px solid var(--border);
}

.auto-only {
  display: none;
}

.frame-only {
  display: none;
}

.log {
  margin: 0;
  min-height: 160px;
  max-height: 280px;
  overflow-y: auto;
  padding: 1rem;
  border-radius: 0.6rem;
  background: rgba(15, 23, 42, 0.4);
  border: 1px solid var(--border);
  font-size: 0.85rem;
  line-height: 1.6;
  white-space: pre-wrap;
}

.app-footer {
  color: var(--muted);
}

code {
  font-family: "JetBrains Mono", "Menlo", "Consolas", monospace;
  background: rgba(148, 163, 184, 0.12);
  padding: 0.1rem 0.3rem;
  border-radius: 0.3rem;
}