:root {
  --font-base: "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Yu Gothic", "Segoe UI", sans-serif;

  --color-bg: #f6f7fb;
  --color-surface: #ffffff;
  --color-border: #e6e8f0;
  --color-text: #23252b;
  --color-text-sub: #686c7a;

  --color-assistant: #6d5efc;
  --color-assistant-bg: #f1efff;
  --color-assistant-dark: #574bd6;

  --color-generate: #ff7a59;
  --color-generate-bg: #fff1ec;
  --color-generate-dark: #e6603f;

  --radius-lg: 20px;
  --radius-md: 12px;
  --shadow-card: 0 4px 24px rgba(31, 35, 60, 0.07);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-base);
  background: linear-gradient(180deg, #f8f9fd 0%, #eef0f8 55%, #f8f9fd 100%);
  background-attachment: fixed;
  color: var(--color-text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* ---------- Header ---------- */
.app-header {
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(230, 232, 240, 0.7);
  box-shadow: 0 4px 20px rgba(31, 35, 60, 0.04);
  padding: 18px 24px;
  position: sticky;
  top: 0;
  z-index: 10;
}

.app-header__inner {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 12px;
}

.app-header__logo {
  font-size: 28px;
}

.app-header__title {
  font-size: 22px;
  font-weight: 800;
  margin: 0;
  letter-spacing: 0.2px;
}

/* ---------- Layout ---------- */
.main-layout {
  max-width: 1280px;
  margin: 0 auto;
  padding: 36px 24px 72px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}

@media (max-width: 900px) {
  .main-layout {
    grid-template-columns: 1fr;
    padding: 24px 16px 56px;
    gap: 20px;
  }
}

/* ---------- Panel ---------- */
.panel {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  padding: 32px;
  box-shadow: var(--shadow-card);
  display: flex;
  flex-direction: column;
}

@media (max-width: 900px) {
  .panel {
    padding: 22px;
  }
}

.panel--assistant {
  border-top: 4px solid var(--color-assistant);
}

.panel--generate {
  border-top: 4px solid var(--color-generate);
}

.panel__badge {
  display: inline-block;
  align-self: flex-start;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 1px;
  color: var(--color-assistant-dark);
  background: var(--color-assistant-bg);
  padding: 5px 12px;
  border-radius: 999px;
  margin-bottom: 14px;
}

.panel__badge--generate {
  color: var(--color-generate-dark);
  background: var(--color-generate-bg);
}

.panel__title {
  font-size: 21px;
  font-weight: 800;
  letter-spacing: 0.1px;
  margin: 0 0 10px;
}

.panel__desc {
  font-size: 14.5px;
  color: var(--color-text-sub);
  margin: 0 0 22px;
}

/* ---------- Card / Fields ---------- */
.card {
  margin-bottom: 20px;
}

.card--row {
  display: flex;
  gap: 18px;
}

.card--row .field-group {
  flex: 1;
}

@media (max-width: 480px) {
  .card--row {
    flex-direction: column;
    gap: 20px;
  }
}

.field-label {
  display: block;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 7px;
}

.select-input,
.text-input {
  width: 100%;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 12px 14px;
  font-size: 15px;
  font-family: inherit;
  background: var(--color-bg);
  color: var(--color-text);
  resize: vertical;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.select-input:focus,
.text-input:focus {
  outline: none;
  border-color: var(--color-assistant);
  box-shadow: 0 0 0 3px rgba(109, 94, 252, 0.15);
}

.panel--generate .select-input:focus,
.panel--generate .text-input:focus {
  border-color: var(--color-generate);
  box-shadow: 0 0 0 3px rgba(255, 122, 89, 0.15);
}

/* ---------- Upload box ---------- */
.upload-box {
  border: 2px dashed #d7d9e6;
  border-radius: var(--radius-md);
  padding: 28px 16px;
  text-align: center;
  cursor: pointer;
  background: var(--color-bg);
  transition: border-color 0.15s, background 0.15s, transform 0.15s;
}

.upload-box:hover {
  border-color: var(--color-assistant);
  background: var(--color-assistant-bg);
  transform: translateY(-1px);
}

.upload-box__icon {
  font-size: 30px;
  margin-bottom: 8px;
}

.upload-box__text {
  font-size: 13.5px;
  color: var(--color-text-sub);
}

.upload-box__filename {
  margin-top: 8px;
  font-size: 13px;
  color: var(--color-assistant-dark);
  font-weight: 600;
  min-height: 18px;
}

.upload-box__note {
  margin-top: 8px;
  font-size: 12px;
  color: var(--color-text-sub);
}

/* ---------- Panel note (persistent info) ---------- */
.panel__note {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--color-generate-dark);
  background: var(--color-generate-bg);
  border: 1px solid rgba(255, 122, 89, 0.25);
  border-radius: var(--radius-md);
  padding: 12px 14px;
  margin: -8px 0 22px;
}

/* ---------- Buttons ---------- */
.btn {
  width: 100%;
  border: none;
  border-radius: var(--radius-md);
  padding: 15px 22px;
  font-size: 15.5px;
  font-weight: 700;
  color: #fff;
  cursor: pointer;
  transition: transform 0.15s, opacity 0.15s, box-shadow 0.15s;
  margin-top: 4px;
}

.btn:hover {
  opacity: 0.95;
  transform: translateY(-1px);
}

.btn:active {
  transform: scale(0.98);
}

.btn--assistant {
  background: linear-gradient(135deg, var(--color-assistant), var(--color-assistant-dark));
  box-shadow: 0 10px 24px -8px rgba(109, 94, 252, 0.6);
}

.btn--generate {
  background: linear-gradient(135deg, var(--color-generate), var(--color-generate-dark));
  box-shadow: 0 10px 24px -8px rgba(255, 122, 89, 0.6);
}

.btn:disabled {
  cursor: not-allowed;
  opacity: 0.6;
  transform: none;
  box-shadow: none;
}

/* ---------- Error box ---------- */
.error-box {
  margin-top: 14px;
  background: #fdecec;
  border: 1px solid #f3b4b4;
  color: #b3261e;
  border-radius: var(--radius-md);
  padding: 13px 15px;
  font-size: 13.5px;
  line-height: 1.6;
  font-weight: 600;
  display: none;
}

.error-box.is-visible {
  display: block;
}

/* ---------- Info banner (generate guidance) ---------- */
.info-banner {
  margin-top: 14px;
  background: var(--color-generate-bg);
  border: 1px solid rgba(255, 122, 89, 0.35);
  color: var(--color-generate-dark);
  border-radius: var(--radius-md);
  padding: 13px 15px;
  font-size: 13.5px;
  line-height: 1.6;
  font-weight: 600;
  display: none;
}

.info-banner.is-visible {
  display: block;
}

/* ---------- Result box (assistant) ---------- */
.result-box {
  margin-top: 20px;
  background: var(--color-assistant-bg);
  border: 1px solid rgba(109, 94, 252, 0.25);
  border-radius: var(--radius-md);
  padding: 16px 18px;
  display: none;
}

.result-box.is-visible {
  display: block;
}

.result-box__label {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.2px;
  color: var(--color-assistant-dark);
  margin-bottom: 10px;
}

.result-box__body {
  font-size: 14.5px;
  line-height: 1.8;
  white-space: pre-line;
  color: var(--color-text);
}

/* ---------- Preview area (generate) ---------- */
.preview-area {
  margin-top: 20px;
  display: none;
}

.preview-area.is-visible {
  display: block;
}

.preview-area .result-box__label {
  color: var(--color-generate-dark);
}

.preview-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 16px;
  margin-top: 12px;
}

.preview-card {
  background: var(--color-generate-bg);
  border: 1px solid rgba(255, 122, 89, 0.22);
  border-radius: var(--radius-md);
  padding: 16px;
  text-align: center;
}

.preview-card__page {
  font-weight: 700;
  font-size: 14px;
  margin-bottom: 4px;
}

.preview-card--locked {
  opacity: 0.9;
}

.preview-card__panels {
  font-size: 12px;
  color: var(--color-text-sub);
  margin-bottom: 12px;
}

.preview-card__thumb {
  background: linear-gradient(160deg, rgba(255, 122, 89, 0.09), rgba(255, 122, 89, 0.02));
  border: 1px solid rgba(255, 122, 89, 0.14);
  border-radius: 12px;
  height: 140px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.preview-card__thumb-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.85);
  box-shadow: 0 2px 8px rgba(31, 35, 60, 0.06);
}

.preview-card__thumb-text {
  font-size: 11px;
  line-height: 1.5;
  color: var(--color-text-sub);
  padding: 0 8px;
}

/* ---------- Footer ---------- */
.app-footer {
  text-align: center;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--color-text-sub);
  border-top: 1px solid var(--color-border);
  padding: 24px 20px 32px;
}