/* ===== Design Tokens ===== */
:root {
  --font: 'Inter', system-ui, -apple-system, sans-serif;
  --bg: #f0f2f5;
  --surface: #ffffff;
  --surface-hover: #f8f9fb;
  --border: #e2e5ea;
  --border-light: #eef0f3;

  --text-primary: #1a1d23;
  --text-secondary: #5f6672;
  --text-muted: #9ba3af;

  --accent: #f97316;
  --accent-light: #fff7ed;
  --accent-border: #fed7aa;

  --green: #16a34a;
  --green-light: #f0fdf4;
  --green-border: #bbf7d0;
  --green-dark: #15803d;

  --blue: #2563eb;
  --blue-light: #eff6ff;
  --blue-border: #bfdbfe;

  --purple: #7c3aed;
  --purple-light: #f5f3ff;
  --purple-border: #ddd6fe;

  --red: #ef4444;
  --red-light: #fef2f2;

  --brand: #2a6aab;

  --radius: 14px;
  --radius-sm: 10px;
  --radius-xs: 8px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,.04), 0 1px 2px rgba(0,0,0,.06);
  --shadow: 0 4px 16px rgba(0,0,0,.06), 0 1px 3px rgba(0,0,0,.04);
  --shadow-lg: 0 12px 40px rgba(0,0,0,.08), 0 4px 12px rgba(0,0,0,.04);
  --transition: .2s cubic-bezier(.4,0,.2,1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
}

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

/* ===== Header ===== */
#app-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 10px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.logo-group {
  display: flex;
  align-items: center;
  gap: 14px;
}

.logo-img {
  width: 48px;
  height: 48px;
  object-fit: contain;
  flex-shrink: 0;
}

#app-title {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -.02em;
  line-height: 1.2;
  color: var(--brand);
}

.subtitle {
  font-size: .78rem;
  color: var(--text-muted);
  font-weight: 500;
}

.header-actions {
  display: flex;
  gap: 8px;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 16px;
  border: none;
  border-radius: var(--radius-xs);
  font-family: var(--font);
  font-size: .85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, var(--green), var(--green-dark));
  color: white;
  box-shadow: 0 2px 8px rgba(22,163,74,.3);
}
.btn-primary:hover {
  box-shadow: 0 4px 14px rgba(22,163,74,.4);
  transform: translateY(-1px);
}

.btn-outline {
  background: var(--surface);
  color: var(--blue);
  border: 1.5px solid var(--blue-border);
}
.btn-outline:hover {
  background: var(--blue-light);
  border-color: var(--blue);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
}
.btn-ghost:hover {
  background: var(--surface-hover);
  color: var(--red);
}

.btn-add {
  background: var(--accent-light);
  color: var(--accent);
  border: 1.5px dashed var(--accent-border);
  padding: 10px 20px;
}
.btn-add:hover {
  background: #fff1e0;
  border-color: var(--accent);
}

/* ===== Cards ===== */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  transition: box-shadow var(--transition);
}
.card:hover {
  box-shadow: var(--shadow-lg);
}

.card-header {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 24px;
}

.card-header h2 {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -.01em;
}

.card-desc {
  font-size: .8rem;
  color: var(--text-muted);
  margin-top: 2px;
}

.section-badge {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-xs);
  font-weight: 800;
  font-size: .9rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.badge-a { background: var(--accent-light); color: var(--accent); }
.badge-b { background: var(--blue-light); color: var(--blue); }
.badge-c { background: var(--purple-light); color: var(--purple); }
.badge-d { background: var(--green-light); color: var(--green); }
.badge-out { background: linear-gradient(135deg, var(--green), var(--green-dark)); color: white; }

/* ===== Main Layout ===== */
#calculator-main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 28px 24px 60px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

/* ===== Table — Section A (Desktop) ===== */
.table-wrap {
  overflow-x: auto;
  margin: 0 -12px;
  padding: 0 12px;
}

#raw-material-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  font-size: .88rem;
}

#raw-material-table thead th {
  text-align: left;
  padding: 10px 12px;
  font-weight: 600;
  font-size: .78rem;
  text-transform: uppercase;
  letter-spacing: .04em;
  color: var(--text-muted);
  border-bottom: 2px solid var(--border);
  white-space: nowrap;
}

#raw-material-table tbody td {
  padding: 6px 12px;
  vertical-align: middle;
  border-bottom: 1px solid var(--border-light);
}

#raw-material-table tbody tr {
  transition: background var(--transition);
}
#raw-material-table tbody tr:hover {
  background: var(--surface-hover);
}

.col-name { min-width: 160px; }
.col-qty, .col-price { width: 160px; }
.col-total { width: 160px; }
.col-action { width: 44px; }

.row-label {
  font-weight: 600;
  color: var(--text-secondary);
  font-size: .88rem;
  white-space: nowrap;
}

/* Input inside table */
.tbl-input {
  width: 100%;
  padding: 9px 12px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-xs);
  font-family: var(--font);
  font-size: .88rem;
  color: var(--text-primary);
  background: var(--surface);
  transition: all var(--transition);
  outline: none;
  font-variant-numeric: tabular-nums;
}
.tbl-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(249,115,22,.12);
}

.row-total {
  font-weight: 700;
  color: var(--blue);
  font-variant-numeric: tabular-nums;
  font-size: .9rem;
}

.btn-remove-row {
  width: 34px;
  height: 34px;
  border: none;
  border-radius: var(--radius-xs);
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
}
.btn-remove-row:hover {
  background: var(--red-light);
  color: var(--red);
}

.table-actions {
  margin-top: 16px;
  display: flex;
  justify-content: center;
}

/* ===== Mobile Card Rows (Section A) ===== */
.mobile-rows {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.mobile-row-card {
  background: var(--surface-hover);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 16px;
  position: relative;
  transition: all var(--transition);
}
.mobile-row-card:hover {
  border-color: var(--border);
}

.mobile-row-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.mobile-row-title {
  font-weight: 700;
  font-size: .9rem;
  color: var(--text-primary);
}

.mobile-row-inputs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.mobile-input-group label {
  display: block;
  font-size: .72rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: .04em;
  margin-bottom: 4px;
}

.mobile-input-group input {
  width: 100%;
  padding: 10px 12px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-xs);
  font-family: var(--font);
  font-size: .95rem;
  font-weight: 500;
  color: var(--text-primary);
  background: var(--surface);
  transition: all var(--transition);
  outline: none;
  font-variant-numeric: tabular-nums;
}
.mobile-input-group input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(249,115,22,.12);
}

.mobile-row-total {
  margin-top: 10px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 10px;
  border-top: 1px solid var(--border-light);
}

.mobile-row-total-label {
  font-size: .78rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: .03em;
}

.mobile-row-total-value {
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--blue);
  font-variant-numeric: tabular-nums;
}

.btn-remove-mobile {
  width: 30px;
  height: 30px;
  border: none;
  border-radius: var(--radius-xs);
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
}
.btn-remove-mobile:hover,
.btn-remove-mobile:active {
  background: var(--red-light);
  color: var(--red);
}

/* Show/hide for responsive */
.desktop-only { display: block; }
.mobile-only  { display: none;  }

/* ===== Section B — Summary Grid ===== */
.summary-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.summary-item {
  background: var(--surface-hover);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: all var(--transition);
}
.summary-item:hover { border-color: var(--border); }

.summary-item.highlight {
  background: var(--blue-light);
  border-color: var(--blue-border);
}

.summary-label {
  font-size: .78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .04em;
  color: var(--text-muted);
}

.summary-value {
  font-size: 1.45rem;
  font-weight: 800;
  font-variant-numeric: tabular-nums;
  color: var(--text-primary);
  letter-spacing: -.02em;
}
.summary-value small {
  font-size: .75rem;
  font-weight: 600;
  color: var(--text-muted);
}

/* ===== Section C — Inputs & Breakdown ===== */
.input-group-stack {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.input-field label {
  display: block;
  font-size: .8rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.input-field input {
  width: 100%;
  padding: 11px 14px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-xs);
  font-family: var(--font);
  font-size: .95rem;
  font-weight: 500;
  color: var(--text-primary);
  background: var(--surface);
  transition: all var(--transition);
  outline: none;
  font-variant-numeric: tabular-nums;
}
.input-field input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(249,115,22,.12);
  background: var(--accent-light);
}
.input-field input::placeholder {
  color: var(--text-muted);
}

.cost-breakdown {
  margin-top: 24px;
  border-top: 2px solid var(--border);
  padding-top: 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.cost-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: .9rem;
  color: var(--text-secondary);
}
.cost-row span:last-child {
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--text-primary);
}
.cost-row.final {
  padding-top: 12px;
  border-top: 2px dashed var(--green-border);
  margin-top: 4px;
}
.cost-row.final span:first-child {
  font-weight: 700;
  color: var(--green-dark);
}
.cost-row.final span:last-child {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--green);
}

/* ===== Section D — Conversion ===== */
.conversion-results {
  margin-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.conv-card {
  background: var(--surface-hover);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: all var(--transition);
}
.conv-card:hover { border-color: var(--border); }

.conv-card.accent {
  background: var(--green-light);
  border-color: var(--green-border);
}

.conv-label {
  font-size: .82rem;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: .03em;
}

.conv-value {
  font-size: 1.2rem;
  font-weight: 800;
  font-variant-numeric: tabular-nums;
  color: var(--text-primary);
}
.conv-card.accent .conv-value {
  color: var(--green);
}

/* ===== Final Output Cards ===== */
.card-output {
  background: linear-gradient(135deg, #f0fdf4 0%, #ecfdf5 50%, #f0fdf4 100%);
  border-color: var(--green-border);
}

.output-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.output-card {
  background: var(--surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 22px 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  text-align: center;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}
.output-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--border);
  border-radius: var(--radius-sm) var(--radius-sm) 0 0;
  transition: background var(--transition);
}
.output-card:hover {
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}
.output-card:hover::before {
  background: var(--blue);
}

.output-card-final {
  border-color: var(--green-border);
  background: linear-gradient(135deg, #f0fdf4, #ffffff);
}
.output-card-final::before {
  background: var(--green);
}
.output-card-final:hover::before {
  background: var(--green-dark);
}

.out-label {
  font-size: .75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .05em;
  color: var(--text-muted);
}

.out-value {
  font-size: 1.5rem;
  font-weight: 800;
  font-variant-numeric: tabular-nums;
  color: var(--text-primary);
  letter-spacing: -.02em;
}
.output-card-final .out-value {
  color: var(--green);
}

/* ===== Toast ===== */
.toast {
  position: fixed;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%) translateY(80px);
  background: var(--text-primary);
  color: white;
  padding: 12px 28px;
  border-radius: 100px;
  font-size: .88rem;
  font-weight: 600;
  box-shadow: var(--shadow-lg);
  z-index: 1000;
  opacity: 0;
  transition: all .35s cubic-bezier(.4,0,.2,1);
  pointer-events: none;
}
.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ===== Footer ===== */
footer {
  text-align: center;
  padding: 24px;
  color: var(--text-muted);
  font-size: .78rem;
}

/* ===== Responsive — Tablet ===== */
@media (max-width: 900px) {
  .two-col {
    grid-template-columns: 1fr;
  }
  .output-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .summary-grid {
    grid-template-columns: 1fr 1fr;
  }
}

/* ===== Responsive — Mobile ===== */
@media (max-width: 640px) {
  .header-inner {
    padding: 10px 14px;
  }

  .logo-img {
    width: 38px;
    height: 38px;
  }

  #app-title {
    font-size: 1.05rem;
  }

  .subtitle {
    font-size: .7rem;
  }

  .btn {
    padding: 8px 10px;
    font-size: .8rem;
  }
  .btn-label {
    display: none;
  }

  #calculator-main {
    padding: 14px 10px 48px;
    gap: 14px;
  }

  .card {
    padding: 18px 14px;
    border-radius: var(--radius-sm);
  }

  .card-header {
    margin-bottom: 16px;
  }

  .card-header h2 {
    font-size: 1rem;
  }

  .section-badge {
    width: 32px;
    height: 32px;
    font-size: .8rem;
  }

  /* Switch table to mobile cards */
  .desktop-only { display: none !important; }
  .mobile-only  { display: flex !important; }

  .summary-grid {
    grid-template-columns: 1fr;
    gap: 10px;
  }
  .summary-item {
    padding: 14px;
  }
  .summary-value {
    font-size: 1.25rem;
  }

  .output-grid {
    grid-template-columns: 1fr;
    gap: 10px;
  }
  .output-card {
    padding: 16px 14px;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    text-align: left;
  }
  .output-card::before {
    width: 4px;
    height: 100%;
    top: 0;
    left: 0;
    right: auto;
    bottom: 0;
    border-radius: var(--radius-sm) 0 0 var(--radius-sm);
  }
  .out-value {
    font-size: 1.2rem;
  }

  .conv-card {
    padding: 14px 16px;
  }
  .conv-value {
    font-size: 1.05rem;
  }

  .cost-row.final span:last-child {
    font-size: 1.05rem;
  }

  .btn-add {
    width: 100%;
    justify-content: center;
    padding: 12px 20px;
  }

  .table-actions {
    margin-top: 12px;
  }
}

/* ===== Small phones ===== */
@media (max-width: 380px) {
  .header-inner {
    padding: 8px 10px;
  }
  .logo-group {
    gap: 10px;
  }
  .logo-img {
    width: 32px;
    height: 32px;
  }
  #app-title {
    font-size: .95rem;
  }
  .header-actions {
    gap: 4px;
  }
  .btn {
    padding: 7px 8px;
  }
  .card {
    padding: 14px 10px;
  }
  .mobile-row-inputs {
    grid-template-columns: 1fr;
  }
}

/* ===== Animations ===== */
@keyframes fadeSlideIn {
  from { opacity: 0; transform: translateY(-8px); }
  to   { opacity: 1; transform: translateY(0); }
}
.row-animate-in {
  animation: fadeSlideIn .3s cubic-bezier(.4,0,.2,1) both;
}

/* ===== Print / PDF ===== */
@media print {
  #app-header, .btn-remove-row, .btn-remove-mobile, .table-actions, .header-actions, footer {
    display: none !important;
  }
  .mobile-only { display: none !important; }
  .desktop-only { display: block !important; }
  body { background: white; }
  .card { box-shadow: none; border: 1px solid #ddd; page-break-inside: avoid; }
}