:root {
  color-scheme: light;
  font-family: "Segoe UI", "Noto Sans TC", Arial, sans-serif;
  --bg: #f4f6f4;
  --panel: #ffffff;
  --ink: #202124;
  --muted: #66706b;
  --line: #dce3de;
  --accent: #246b4f;
  --accent-dark: #174c38;
  --warning: #c77916;
  --warning-bg: #fff6e7;
  --ok-bg: #f3faf5;
  --danger: #b3261e;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--ink);
}

.app-shell {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 32px 0;
  display: grid;
  grid-template-columns: minmax(280px, 420px) 1fr;
  gap: 24px;
}

.item-panel,
.inventory-panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 24px;
  box-shadow: 0 16px 40px rgba(32, 33, 36, 0.08);
}

.panel-heading {
  margin-bottom: 20px;
}

.panel-heading.row,
.panel-heading.with-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.auth-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex-wrap: wrap;
  gap: 8px;
}

.current-account {
  color: var(--accent);
  font-weight: 800;
}

.eyebrow {
  margin: 0 0 6px;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2 {
  margin: 0;
  line-height: 1.2;
}

h1 {
  font-size: 2rem;
}

h2 {
  font-size: 1.4rem;
}

.item-form,
.auth-form {
  display: grid;
  gap: 16px;
}

label {
  display: grid;
  gap: 8px;
  color: #333936;
  font-weight: 700;
}

input,
textarea {
  width: 100%;
  border: 1px solid #c8d2cc;
  border-radius: 6px;
  padding: 12px;
  color: var(--ink);
  font: inherit;
  background: #fff;
}

textarea {
  resize: vertical;
}

input:focus,
textarea:focus {
  outline: 3px solid rgba(36, 107, 79, 0.18);
  border-color: var(--accent);
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

button {
  border: 0;
  border-radius: 6px;
  padding: 12px 16px;
  min-height: 44px;
  color: white;
  background: var(--accent);
  font: inherit;
  font-weight: 800;
  cursor: pointer;
}

button:hover {
  background: var(--accent-dark);
}

button:disabled {
  cursor: progress;
  opacity: 0.68;
}

.secondary-button {
  color: var(--accent);
  background: #e8f1ec;
}

.secondary-button:hover {
  color: white;
}

.hidden {
  display: none;
}

.form-message {
  min-height: 22px;
  margin: 0;
  color: var(--muted);
  font-weight: 700;
}

.form-message.error {
  color: var(--danger);
}

.form-message.success {
  color: var(--accent);
}

.items-list {
  display: grid;
  gap: 12px;
}

.item-card {
  border: 1px solid var(--line);
  border-left: 5px solid var(--accent);
  border-radius: 8px;
  padding: 16px;
  background: var(--ok-bg);
}

.item-card.low-stock {
  border-left-color: var(--warning);
  background: var(--warning-bg);
}

.item-card header {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
}

.item-card h3 {
  margin: 0;
  font-size: 1.05rem;
}

.stock-badge {
  min-width: 70px;
  height: 32px;
  display: inline-grid;
  place-items: center;
  border-radius: 999px;
  color: #fff;
  background: var(--accent);
  font-weight: 900;
}

.low-stock .stock-badge {
  background: var(--warning);
}

.item-meta {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.empty-state {
  margin: 0;
  padding: 24px;
  border: 1px dashed #b8c2bd;
  border-radius: 8px;
  color: var(--muted);
  text-align: center;
}

.auth-modal {
  position: fixed;
  inset: 0;
  z-index: 10;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(0, 0, 0, 0.5);
}

.auth-modal.active {
  display: flex;
}

.auth-dialog {
  position: relative;
  width: min(100%, 380px);
  border-radius: 8px;
  padding: 24px;
  background: var(--panel);
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.24);
}

.auth-dialog h2 {
  margin-bottom: 18px;
}

.close-button {
  position: absolute;
  top: 10px;
  right: 10px;
  width: 36px;
  min-height: 36px;
  padding: 0;
  border-radius: 50%;
  color: var(--muted);
  background: transparent;
  font-size: 1.5rem;
  line-height: 1;
}

.close-button:hover {
  color: var(--ink);
  background: #eef2ef;
}

@media (max-width: 820px) {
  .app-shell {
    grid-template-columns: 1fr;
    width: min(100% - 24px, 560px);
    padding: 20px 0;
  }
}

@media (max-width: 520px) {
  .item-panel,
  .inventory-panel {
    padding: 18px;
  }

  .panel-heading.row,
  .panel-heading.with-actions,
  .item-card header {
    align-items: stretch;
    flex-direction: column;
  }

  .auth-actions {
    justify-content: flex-start;
  }

  .form-grid {
    grid-template-columns: 1fr;
  }
}