/* ===================================
   クレカ節約アドバイザー - スタイルシート
   デザイン: Exaggerated Minimalism
   フォント: Noto Serif JP / Noto Sans JP
   =================================== */

@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@300;400;500;700&family=Noto+Serif+JP:wght@400;600;700&display=swap');

/* --- CSS Variables --- */
:root {
  --color-primary: #18181B;
  --color-secondary: #3F3F46;
  --color-cta: #2563EB;
  --color-cta-hover: #1D4ED8;
  --color-bg: #FAFAFA;
  --color-surface: #FFFFFF;
  --color-border: #E4E4E7;
  --color-text: #09090B;
  --color-text-muted: #71717A;

  --color-ok: #16A34A;
  --color-ok-bg: #F0FDF4;
  --color-ok-border: #BBF7D0;
  --color-warning: #D97706;
  --color-warning-bg: #FFFBEB;
  --color-warning-border: #FDE68A;
  --color-over: #DC2626;
  --color-over-bg: #FEF2F2;
  --color-over-border: #FECACA;

  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08), 0 2px 6px rgba(0,0,0,0.04);
  --shadow-lg: 0 10px 30px rgba(0,0,0,0.10), 0 4px 12px rgba(0,0,0,0.06);

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;

  --font-sans: 'Noto Sans JP', system-ui, sans-serif;
  --font-serif: 'Noto Serif JP', Georgia, serif;

  --transition: 180ms ease;
}

/* --- Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 16px; scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* --- Navigation --- */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav-inner {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 20px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-family: var(--font-serif);
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: -0.01em;
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-brand svg { flex-shrink: 0; }

.nav-tabs {
  display: flex;
  gap: 4px;
}

.nav-tab {
  padding: 6px 16px;
  border-radius: 6px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-muted);
  cursor: pointer;
  border: none;
  background: transparent;
  transition: color var(--transition), background var(--transition);
  font-family: var(--font-sans);
}

.nav-tab:hover { color: var(--color-primary); background: var(--color-border); }

.nav-tab.active {
  color: var(--color-cta);
  background: #EFF6FF;
}

/* --- Main Layout --- */
.main {
  max-width: 800px;
  margin: 0 auto;
  padding: 48px 20px 80px;
}

/* --- Section Visibility --- */
.section { display: none; }
.section.active { display: block; }

/* --- Page Heading --- */
.page-heading {
  font-family: var(--font-serif);
  font-size: clamp(1.75rem, 5vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.2;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.page-subtitle {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  margin-bottom: 36px;
  line-height: 1.6;
}

/* --- Card --- */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-sm);
}

/* --- Drop Zone --- */
.drop-zone {
  border: 2px dashed var(--color-border);
  border-radius: var(--radius-md);
  padding: 48px 24px;
  text-align: center;
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition);
  background: var(--color-bg);
}

.drop-zone:hover, .drop-zone.dragover {
  border-color: var(--color-cta);
  background: #EFF6FF;
}

.drop-zone-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 16px;
  color: var(--color-text-muted);
}

.drop-zone-text {
  font-size: 0.9375rem;
  color: var(--color-secondary);
  margin-bottom: 16px;
  line-height: 1.6;
}

.drop-zone-hint {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-top: 12px;
  font-weight: 300;
}

.file-info {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 16px;
  padding: 12px 16px;
  background: #EFF6FF;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  color: var(--color-cta);
  font-weight: 500;
}

.file-info.hidden { display: none; }

.file-info svg { flex-shrink: 0; }

/* --- Upload Options --- */
.upload-options {
  margin-top: 28px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-label {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-secondary);
}

.form-input {
  padding: 10px 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-size: 0.9375rem;
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-surface);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
  max-width: 200px;
}

.form-input:focus {
  border-color: var(--color-cta);
  box-shadow: 0 0 0 3px rgba(37,99,235,0.12);
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 24px;
  border-radius: var(--radius-sm);
  font-size: 0.9375rem;
  font-weight: 600;
  font-family: var(--font-sans);
  cursor: pointer;
  border: none;
  transition: background var(--transition), opacity var(--transition), transform var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-cta);
  color: #FFFFFF;
}

.btn-primary:hover:not(:disabled) {
  background: var(--color-cta-hover);
}

.btn-primary:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.btn-secondary {
  background: transparent;
  color: var(--color-secondary);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  background: var(--color-bg);
  color: var(--color-primary);
}

.btn-lg {
  padding: 14px 32px;
  font-size: 1rem;
  width: 100%;
}

/* --- Loading --- */
.loading-overlay {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 20px;
  padding: 80px 20px;
  color: var(--color-text-muted);
}

.loading-overlay.active { display: flex; }

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--color-border);
  border-top-color: var(--color-cta);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin { to { transform: rotate(360deg); } }

/* --- Results Header --- */
.results-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 8px;
}

.results-meta {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin-bottom: 32px;
}

/* --- Summary Cards --- */
.summary-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-bottom: 28px;
}

.summary-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 20px;
  box-shadow: var(--shadow-sm);
}

.summary-card-label {
  font-size: 0.75rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--color-text-muted);
  margin-bottom: 8px;
}

.summary-card-value {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-primary);
  line-height: 1.2;
}

.summary-card.over .summary-card-value { color: var(--color-over); }
.summary-card.ok .summary-card-value { color: var(--color-ok); }

/* --- Chart --- */
.chart-container {
  position: relative;
  height: 320px;
  margin-bottom: 28px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-sm);
}

.chart-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-secondary);
  margin-bottom: 16px;
}

/* --- Table --- */
.table-wrapper {
  margin-bottom: 28px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.table-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-secondary);
  padding: 20px 24px 0;
  margin-bottom: 16px;
}

.table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
}

.table th {
  text-align: left;
  padding: 10px 16px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
}

.table th:last-child, .table td:last-child { text-align: center; }
.table th:nth-child(2), .table td:nth-child(2),
.table th:nth-child(3), .table td:nth-child(3),
.table th:nth-child(4), .table td:nth-child(4),
.table th:nth-child(5), .table td:nth-child(5) { text-align: right; }

.table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text);
}

.table tr:last-child td { border-bottom: none; }

.table tr:hover td { background: #F9F9FB; }

/* --- Status Badge --- */
.status-badge {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  border-radius: 100px;
  font-size: 0.75rem;
  font-weight: 600;
}

.status-ok {
  background: var(--color-ok-bg);
  color: var(--color-ok);
  border: 1px solid var(--color-ok-border);
}

.status-warning {
  background: var(--color-warning-bg);
  color: var(--color-warning);
  border: 1px solid var(--color-warning-border);
}

.status-over {
  background: var(--color-over-bg);
  color: var(--color-over);
  border: 1px solid var(--color-over-border);
}

/* --- Advice Cards --- */
.advice-section { margin-bottom: 28px; }

.advice-heading {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 16px;
}

.advice-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-over);
  border-radius: var(--radius-md);
  padding: 20px;
  margin-bottom: 12px;
  box-shadow: var(--shadow-sm);
}

.advice-card.warning { border-left-color: var(--color-warning); }

.advice-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 8px;
}

.advice-card-category {
  font-weight: 700;
  font-size: 0.9375rem;
  color: var(--color-primary);
}

.advice-card-amount {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-over);
}

.advice-card.warning .advice-card-amount { color: var(--color-warning); }

.advice-text {
  font-size: 0.875rem;
  color: var(--color-secondary);
  line-height: 1.65;
}

/* --- History --- */
.history-empty {
  text-align: center;
  padding: 64px 20px;
  color: var(--color-text-muted);
  font-size: 0.9375rem;
}

.history-list {
  display: flex;
  flex-direction: column;
  gap: 1px;
  background: var(--color-border);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.history-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 20px;
  background: var(--color-surface);
  cursor: pointer;
  transition: background var(--transition);
}

.history-item:hover { background: #F5F5FF; }

.history-item-icon {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  background: #EFF6FF;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  color: var(--color-cta);
}

.history-item-body { flex: 1; min-width: 0; }

.history-item-date {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-bottom: 2px;
}

.history-item-title {
  font-weight: 600;
  font-size: 0.9375rem;
  color: var(--color-primary);
}

.history-item-meta {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 2px;
}

.history-item-amount {
  font-weight: 700;
  font-size: 0.9375rem;
  color: var(--color-primary);
  font-family: var(--font-serif);
}

.history-item-count {
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

/* --- Error Toast --- */
.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(80px);
  background: #1E1E1E;
  color: #fff;
  padding: 12px 20px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  box-shadow: var(--shadow-lg);
  z-index: 100;
  transition: transform 0.3s cubic-bezier(0.34,1.56,0.64,1);
  max-width: calc(100vw - 48px);
  text-align: center;
}

.toast.show { transform: translateX(-50%) translateY(0); }

/* --- Responsive --- */
@media (max-width: 600px) {
  .main { padding: 32px 16px 60px; }
  .nav-inner { padding: 0 16px; }
  .card { padding: 20px; }

  .summary-cards {
    grid-template-columns: 1fr;
    gap: 10px;
  }

  .summary-card { padding: 16px; }
  .summary-card-value { font-size: 1.25rem; }

  .chart-container { height: 260px; }

  .table-wrapper { overflow-x: auto; }
  .table { min-width: 500px; }

  .results-header { flex-direction: column; align-items: flex-start; }
  .page-heading { font-size: 1.625rem; }
}

/* --- prefers-reduced-motion --- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; }
  .spinner { animation: none; border-color: var(--color-cta); }
}