:root {
  --color-bg: #f4f6f9;
  --color-card: #ffffff;
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-secondary: #10b981;
  --color-secondary-dark: #059669;
  --color-danger: #ef4444;
  --color-danger-dark: #dc2626;
  --color-text: #1f2937;
  --color-muted: #6b7280;
  --color-border: #e5e7eb;
  --radius: 16px;
}

* { box-sizing: border-box; }

/* hidden属性は必ず優先させる（.scanner-overlay等、classでdisplayを指定している要素があっても
   JSでの hidden 切り替えが効かなくなるのを防ぐ） */
[hidden] { display: none !important; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", "Segoe UI", sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
}

.app {
  max-width: 480px;
  margin: 0 auto;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  padding: 24px 16px 96px;
}

.app-header {
  text-align: center;
  padding: 32px 0 16px;
}
.logo { font-size: 48px; }
.app-header h1 { margin: 8px 0; font-size: 26px; }
.tagline { color: var(--color-muted); font-size: 14px; line-height: 1.6; }

.top-actions {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-top: 24px;
  flex: 1;
}

.big-button {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: 32px 16px;
  border-radius: var(--radius);
  text-decoration: none;
  color: #fff;
  box-shadow: 0 4px 14px rgba(0,0,0,0.08);
  transition: transform 0.1s ease;
}
.big-button:active { transform: scale(0.98); }
.big-button--send { background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark)); }
.big-button--receive { background: linear-gradient(135deg, var(--color-secondary), var(--color-secondary-dark)); }
.big-button__icon { font-size: 40px; }
.big-button__label { font-size: 20px; font-weight: 700; }
.big-button__desc { font-size: 13px; opacity: 0.9; }

.app-footer {
  text-align: center;
  color: var(--color-muted);
  font-size: 12px;
  padding-top: 24px;
  line-height: 1.6;
}

.app-footer--fixed {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 12px 16px calc(12px + env(safe-area-inset-bottom));
  background: linear-gradient(to top, var(--color-bg) 60%, transparent);
}

.page-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 0 16px;
}
.page-header h1 { font-size: 20px; margin: 0; }
.back-link {
  text-decoration: none;
  color: var(--color-text);
  font-size: 20px;
  width: 36px; height: 36px;
  display: flex; align-items: center; justify-content: center;
  border-radius: 50%;
  background: var(--color-card);
}

.page-main { flex: 1; display: flex; flex-direction: column; gap: 16px; }
.page-main--center { align-items: center; justify-content: center; }

.card {
  background: var(--color-card);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: 0 2px 10px rgba(0,0,0,0.06);
}

.step-label {
  font-size: 12px;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: 0.05em;
  margin: 0 0 8px;
}
.hint { color: var(--color-muted); font-size: 13px; line-height: 1.7; margin: 0 0 16px; }

.qr-canvas {
  display: flex;
  justify-content: center;
  padding: 16px;
  background: #fff;
  border-radius: 12px;
  margin-bottom: 16px;
}

.link-row {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
}
.link-row input {
  flex: 1;
  padding: 10px 12px;
  border-radius: 10px;
  border: 1px solid var(--color-border);
  font-size: 13px;
  color: var(--color-muted);
  background: #f9fafb;
}

.btn {
  display: block;
  width: 100%;
  padding: 14px;
  border-radius: 12px;
  border: none;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  text-align: center;
}
.btn-primary { background: var(--color-primary); color: #fff; }
.btn-primary:disabled { background: #93c5fd; cursor: not-allowed; }
.btn-secondary { background: #eef2ff; color: var(--color-primary-dark); width: auto; padding: 10px 16px; }
.btn-outline { background: #fff; color: var(--color-primary); border: 1.5px solid var(--color-primary); }
.btn-danger { background: var(--color-danger); color: #fff; }
.btn-outline-danger { background: #fff; color: var(--color-danger); border: 1.5px solid var(--color-danger); }
#delete-all-btn { margin-top: 14px; }

.status-text {
  text-align: center;
  color: var(--color-muted);
  font-size: 13px;
  margin: 16px 0 0;
}

.pairing-toggle-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 16px;
}
.pairing-toggle-row .btn-outline {
  width: auto;
  padding: 10px 16px;
  font-size: 13px;
}
.pairing-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-secondary-dark);
  background: #ecfdf5;
  padding: 8px 14px;
  border-radius: 100px;
}

#pairing-panel {
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 16px;
  margin-bottom: 16px;
  background: #f9fafb;
}

.dropzone {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 32px 16px;
  border: 2px dashed var(--color-border);
  border-radius: 12px;
  text-align: center;
  color: var(--color-muted);
  font-size: 13px;
  cursor: pointer;
  margin-bottom: 16px;
  transition: border-color 0.15s ease, background 0.15s ease;
}
.dropzone--over { border-color: var(--color-primary); background: #eff6ff; }
.dropzone__icon { font-size: 32px; color: var(--color-primary); }

.list-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}
.checkbox-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--color-muted);
  white-space: nowrap;
}
.list-toolbar .btn-primary { width: auto; padding: 10px 16px; font-size: 13px; }

.file-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.file-item {
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 12px;
}
.file-item__row {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
}
.file-item__name {
  font-size: 14px;
  font-weight: 600;
  word-break: break-all;
}
.file-item__meta {
  font-size: 12px;
  color: var(--color-muted);
  margin-top: 4px;
}
.file-item__progress {
  height: 6px;
  border-radius: 4px;
  background: var(--color-border);
  overflow: hidden;
  margin-top: 8px;
}
.file-item__progress-bar {
  height: 100%;
  background: var(--color-primary);
  transition: width 0.2s ease;
}
.file-item__status { font-size: 12px; color: var(--color-muted); margin-top: 6px; }
.file-item__status--error { color: var(--color-danger); }

/* 送信側のアップロード一覧：選んだ順に並ぶ写真ギャラリー風グリッド */
.gallery {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(96px, 1fr));
  gap: 10px;
}
.gallery-item {
  position: relative;
  aspect-ratio: 1 / 1;
  border-radius: 12px;
  overflow: hidden;
  background: var(--color-border);
}
.gallery-item__thumb {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.gallery-item__icon {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 30px;
  background: #eef2ff;
}
.gallery-item__overlay {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  padding: 6px 8px 7px;
  background: linear-gradient(to top, rgba(0,0,0,0.72), rgba(0,0,0,0));
  color: #fff;
}
.gallery-item__name {
  font-size: 10.5px;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.gallery-item__progress {
  height: 4px;
  border-radius: 3px;
  background: rgba(255,255,255,0.35);
  overflow: hidden;
  margin-top: 4px;
}
.gallery-item__progress-bar {
  height: 100%;
  background: #fff;
  width: 0%;
  transition: width 0.2s ease;
}
.gallery-item__badge {
  position: absolute;
  top: 6px;
  right: 6px;
  font-size: 13px;
  background: rgba(0,0,0,0.55);
  color: #fff;
  border-radius: 50%;
  width: 22px;
  height: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.gallery-item--error .gallery-item__overlay { background: linear-gradient(to top, rgba(185,28,28,0.85), rgba(185,28,28,0)); }

/* 受信側：選択してダウンロードするためのギャラリータイル */
.gallery-item__pick {
  display: block;
  width: 100%;
  height: 100%;
  position: relative;
  cursor: pointer;
}
.gallery-item__pick input {
  position: absolute;
  width: 1px; height: 1px;
  opacity: 0;
  pointer-events: none;
}
.gallery-item__pick input:disabled ~ * { opacity: 0.6; }
.gallery-item__pick:has(input:disabled) { cursor: default; }
.gallery-item__check-badge {
  position: absolute;
  top: 6px;
  left: 6px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: rgba(255,255,255,0.9);
  color: var(--color-primary);
  border: 1.5px solid var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  opacity: 0;
  transform: scale(0.7);
  transition: opacity 0.12s ease, transform 0.12s ease;
  z-index: 2;
}
.gallery-item__pick input:checked ~ .gallery-item__check-badge {
  opacity: 1;
  transform: scale(1);
  background: var(--color-primary);
  color: #fff;
}
.gallery-item:has(input:checked) { outline: 3px solid var(--color-primary); outline-offset: -3px; }
.gallery-item__submeta { color: rgba(255,255,255,0.85); font-size: 10.5px; margin-top: 2px; }

.scanner-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.85);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  padding: 24px;
}
.scanner-box {
  background: #111827;
  border-radius: 16px;
  padding: 16px;
  width: 100%;
  max-width: 360px;
  text-align: center;
  color: #fff;
}
.scanner-box p { font-size: 13px; margin: 0 0 12px; }
.scanner-box video {
  width: 100%;
  border-radius: 12px;
  margin-bottom: 12px;
  background: #000;
}

.filepo-banner {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--color-danger);
  color: #fff;
  padding: 14px 20px;
  text-align: center;
  font-weight: 600;
  font-size: 14px;
  line-height: 1.5;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
  animation: filepo-banner-in 0.25s ease-out;
}

@keyframes filepo-banner-in {
  from { transform: translateY(-100%); }
  to { transform: translateY(0); }
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #0f172a;
    --color-card: #1e293b;
    --color-text: #f1f5f9;
    --color-muted: #94a3b8;
    --color-border: #334155;
  }
  .link-row input { background: #0f172a; color: var(--color-muted); }
  .btn-secondary { background: #1e3a8a33; color: #93c5fd; }
  .qr-canvas { background: #fff; }
}