:root {
  color-scheme: light;
  --bg: #f5f7fb;
  --panel: #ffffff;
  --primary: #0f6b64;
  --primary-dark: #0b4f4a;
  --accent: #dff6f5;
  --text: #1b2430;
  --muted: #597084;
  --border: #dfe7ef;
  --danger: #c94f4f;
  --success: #1d7d5c;
  --shadow: 0 15px 35px rgba(20, 31, 48, 0.08);
}

body.dark {
  color-scheme: dark;
  --bg: #101821;
  --panel: #18252f;
  --primary: #74d0c2;
  --primary-dark: #a6e7df;
  --accent: #112b2b;
  --text: #edf5fb;
  --muted: #b0c7d8;
  --border: #2a3d4d;
  --danger: #ff8a8a;
  --success: #7ad9b0;
  --shadow: 0 15px 35px rgba(0, 0, 0, 0.35);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background: var(--bg);
  color: var(--text);
}

button,
input {
  font: inherit;
}

.container {
  width: min(1100px, 92%);
  margin: 0 auto;
}

.topbar {
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 10;
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 76px;
  padding: 10px 0;
}

.nav-wrap h1 {
  margin: 0;
  font-size: 1.5rem;
  white-space: nowrap;
  flex-shrink: 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.brand-logo {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  display: block;
  object-fit: contain;
}

.brand h1 {
  font-size: 1.5rem;
}

nav {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  flex: 1;
  justify-content: center;
}

.dashboard {
  display: block;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 14px;
  margin: 20px 0;
}

.stat-card,
.panel-block,
.history-item,
.comparison-item {
  background: #f9fbfd;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

body.dark .stat-card,
body.dark .panel-block,
body.dark .history-item,
body.dark .comparison-item {
  background: #13212b;
}

.stat-card span {
  display: block;
  color: var(--muted);
  font-size: 0.85rem;
  margin-bottom: 8px;
}

.stat-card strong {
  font-size: 1.55rem;
}

.stat-note {
  display: block;
  margin-top: 8px;
  color: var(--muted);
  font-size: 0.75rem;
  line-height: 1.4;
}

.dashboard-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px;
}

.history-list,
.comparison-list {
  display: grid;
  gap: 10px;
}

.history-item,
.comparison-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.history-item small,
.comparison-item small {
  color: var(--muted);
}

.history-actions {
  display: flex;
  gap: 8px;
  margin-left: auto;
}

.history-actions button {
  padding: 6px 9px;
  font-size: 0.8rem;
}

.history-actions .danger {
  color: #a12626;
  border-color: #e3aaaa;
  background: #fff5f5;
}

body.dark .history-actions .danger {
  color: #ffb0b0;
  border-color: #754141;
  background: #321d1d;
}

.dashboard-loading {
  margin: 18px 0;
  color: var(--muted);
}

.nav-btn,
.tab-btn,
.calc-tab,
button {
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text);
  border-radius: 8px;
  padding: 9px 14px;
  cursor: pointer;
  transition: all 0.15s ease;
  white-space: nowrap;
}

.nav-btn {
  flex-shrink: 0;
}

.nav-btn.active,
.tab-btn.active,
.calc-tab.active,
button.primary,
button.secondary {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

button.secondary {
  background: var(--panel);
  color: var(--primary);
  border-color: var(--primary);
  flex-shrink: 0;
}

button.primary {
  margin-top: 18px;
}

/* In dark mode the primary colour is light teal, so use a dark text for contrast. */
body.dark .nav-btn.active,
body.dark .tab-btn.active,
body.dark .calc-tab.active,
body.dark button.primary,
body.dark .auth-form button,
body.dark .primary {
  color: #0b4f4a;
}

body.dark button.secondary {
  color: #74d0c2;
  border-color: #74d0c2;
}

.auth-area {
  display: flex;
  align-items: center;
  gap: 12px;
}

.user-badge {
  font-weight: 700;
  color: var(--primary);
}

.main-panel {
  padding: 28px 0 60px;
}

.page {
  display: none;
}

.page.active {
  display: block;
}

.hero {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 26px;
  align-items: center;
}

.eyebrow {
  font-size: .8rem;
  letter-spacing: .12rem;
  text-transform: uppercase;
  color: var(--primary);
  font-weight: 700;
}

.hero h2 {
  font-size: clamp(2rem, 4vw, 3rem);
  margin: 0 0 12px;
}

.mini-summary {
  margin-top: 14px;
  padding: 10px 12px;
  background: #f9fbfd;
  border: 1px solid var(--border);
  border-radius: 10px;
}

body.dark .mini-summary {
  background: #13212b;
}

.auth-box,
.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
  padding: 22px;
}

.tabs,
.calc-tabs {
  display: flex;
  gap: 10px;
  margin-bottom: 16px;
}

.auth-form {
  display: none;
}

.auth-form.active {
  display: block;
}

label {
  display: block;
  margin-bottom: 14px;
  font-weight: 600;
  color: var(--text);
}

input {
  width: 100%;
  margin-top: 8px;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 11px 12px;
  background: var(--panel);
  color: var(--text);
}

.auth-form button,
.primary {
  width: 100%;
  padding: 12px 18px;
  border: none;
  border-radius: 10px;
  background: var(--primary);
  color: #fff;
  cursor: pointer;
}

.message {
  min-height: 24px;
  margin-top: 14px;
  color: var(--primary-dark);
  font-weight: 600;
}

.card h2 {
  margin-top: 0;
}

.calc-panel {
  display: none;
}

.calc-panel.active {
  display: block;
}

.field-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 12px;
}

.result-box {
  margin-top: 20px;
  background: var(--accent);
  border: 1px solid #bae3df;
  border-radius: 12px;
  padding: 16px;
}

.result-box h3 {
  margin-top: 0;
}

.result-box ul {
  margin: 10px 0 0;
  padding-left: 20px;
}

.deadline-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-bottom: 18px;
}

.deadline-item {
  background: #f9fbfd;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

body.dark .deadline-item {
  background: #13212b;
}

.guide-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin: 20px 0;
}

.payment-summary {
  margin: 18px 0;
  padding: 18px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--accent);
}

.example-box {
  margin-top: 20px;
  background: #f9fbfd;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

body.dark .example-box,
body.dark .payment-summary {
  background: #13212b;
}

.example-section {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
}

.example-links {
  margin-top: 18px;
}

.example-box a {
  display: block;
  margin-top: 10px;
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
}

/* Home "tax snapshot" panel */
.welcome-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 8px;
}

.welcome-head h3 {
  margin: 0;
}

.tax-year-chip {
  background: var(--accent);
  border: 1px solid var(--border);
  color: var(--primary-dark);
  font-weight: 700;
  font-size: 0.75rem;
  padding: 4px 10px;
  border-radius: 999px;
  white-space: nowrap;
}

body.dark .tax-year-chip {
  color: #74d0c2;
}

.welcome-name {
  margin: 4px 0 12px;
  color: var(--muted);
}

.home-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin: 12px 0;
}

.home-stat {
  background: #f9fbfd;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px;
}

body.dark .home-stat {
  background: #13212b;
}

.home-stat span {
  display: block;
  color: var(--muted);
  font-size: 0.72rem;
  margin-bottom: 6px;
}

.home-stat strong {
  font-size: 1.15rem;
}

.home-stat.highlight {
  border-color: var(--primary);
  background: var(--accent);
}

body.dark .home-stat.highlight {
  background: #13282c;
}

.muted-text {
  color: var(--muted);
  font-size: 0.72rem;
}

.home-actions {
  display: grid;
  grid-gap: 10px;
  margin-top: 14px;
}

.home-actions .primary {
  margin-top: 0;
}

/* Calculator expenses + set-aside + disclaimer */
.expenses-box {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

.set-aside {
  margin: 12px 0;
  padding: 12px 14px;
  background: var(--accent);
  border: 1px solid #bae3df;
  border-radius: 12px;
  display: flex;
  align-items: baseline;
  gap: 10px;
}

body.dark .set-aside {
  border-color: #2a3d4d;
}

.set-aside span {
  font-size: 1.15rem;
  color: var(--primary-dark);
}

.set-aside small {
  color: var(--muted);
}

.disclaimer {
  margin-top: 14px;
  color: var(--muted);
  font-size: 0.8rem;
}

/* Home update board / changelog */
.update-board {
  margin-top: 34px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.update-board h3 {
  margin: 0 0 14px;
}

.update-card {
  background: #f9fbfd;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px 18px;
}

body.dark .update-card {
  background: #13212b;
}

.update-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
}

.update-version {
  background: var(--accent);
  border: 1px solid #bae3df;
  color: var(--primary-dark);
  font-weight: 800;
  font-size: 0.8rem;
  padding: 3px 10px;
  border-radius: 6px;
}

body.dark .update-version {
  border-color: #2a3d4d;
}

.update-date {
  color: var(--muted);
  font-size: 0.78rem;
}

.update-list {
  margin: 0;
  padding-left: 18px;
}

.update-list li {
  margin-bottom: 10px;
  line-height: 1.5;
}

.update-list li:last-child {
  margin-bottom: 0;
}

.update-list strong {
  color: var(--primary-dark);
}

body.dark .update-list strong {
  color: inherit;
}

.hidden {
  display: none !important;
}

@media (max-width: 720px) {
  .nav-wrap {
    flex-direction: column;
    align-items: flex-start;
    padding: 16px 0;
  }

  nav {
    width: 100%;
    justify-content: flex-start;
  }

  .nav-btn,
  .tab-btn,
  .calc-tab,
  button,
  .secondary {
    width: auto;
    min-width: 0;
  }

  .auth-area {
    width: 100%;
    justify-content: space-between;
    flex-wrap: wrap;
  }

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

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

  .tabs,
  .calc-tabs {
    flex-wrap: wrap;
  }
}

@media (max-width: 480px) {
  .container {
    width: min(94%, 1100px);
  }

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

  .nav-wrap h1 {
    font-size: 1.2rem;
  }

  .card,
  .auth-box {
    padding: 16px;
  }

  .stat-card strong {
    font-size: 1.2rem;
  }
}