:root {
  color-scheme: dark;
  --bg: #0b0d10;
  --bg-accent: #131922;
  --panel: rgba(16, 20, 26, 0.96);
  --panel-strong: #10151b;
  --panel-soft: #1a222b;
  --text: #f5f7fa;
  --muted: #93a0ae;
  --line: rgba(255, 255, 255, 0.09);
  --accent: #ffb000;
  --accent-strong: #ffd364;
  --accent-contrast: #171200;
  --danger: #ff6b6b;
  --shadow: 0 18px 38px rgba(0, 0, 0, 0.32);
  --font-stack: "SF Pro Text", "SF Pro Display", ui-rounded, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --radius-lg: 1.2rem;
  --radius-md: 0.95rem;
  --radius-sm: 0.75rem;
  --keyboard-height: 15.2rem;
}

html[data-theme="daylight"] {
  color-scheme: light;
  --bg: #f4ecd9;
  --bg-accent: #dfd3bb;
  --panel: rgba(255, 250, 240, 0.97);
  --panel-strong: #fff9eb;
  --panel-soft: #efe4cb;
  --text: #15181d;
  --muted: #535b66;
  --line: rgba(21, 24, 29, 0.13);
  --accent: #b95d00;
  --accent-strong: #dc7a17;
  --accent-contrast: #fff4de;
  --danger: #a13030;
  --shadow: 0 16px 30px rgba(69, 49, 16, 0.14);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  height: 100%;
  overflow: hidden;
}

body {
  font-family: var(--font-stack);
  color: var(--text);
  background:
    radial-gradient(circle at top right, rgba(255, 176, 0, 0.09), transparent 28%),
    linear-gradient(180deg, var(--bg-accent), var(--bg));
  line-height: 1.35;
}

button,
input,
summary {
  font: inherit;
}

button,
input {
  border-radius: var(--radius-sm);
}

button {
  min-height: 2.65rem;
  border: 1px solid transparent;
  background: var(--accent);
  color: var(--accent-contrast);
  font-weight: 700;
  padding: 0.62rem 0.82rem;
  touch-action: manipulation;
}

button:focus-visible,
input:focus-visible,
summary:focus-visible {
  outline: 3px solid var(--accent-strong);
  outline-offset: 2px;
}

button:active {
  transform: translateY(1px);
}

input {
  width: 100%;
  min-height: 2.7rem;
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--panel-strong) 90%, transparent);
  color: var(--text);
  padding: 0.68rem 0.8rem;
}

::placeholder {
  color: var(--muted);
}

.app-shell {
  width: min(100%, 37rem);
  height: 100svh;
  margin: 0 auto;
  padding:
    calc(0.12rem + env(safe-area-inset-top))
    0.75rem
    calc(0.45rem + env(safe-area-inset-bottom));
  display: flex;
  flex-direction: column;
  gap: 0.32rem;
}

body.keyboard-open .app-shell {
  padding-bottom: calc(var(--keyboard-height) + 0.58rem + env(safe-area-inset-bottom));
}

body.keyboard-open .install-help {
  display: none;
}

body.keyboard-open:not([data-active-tool="calc"]) .display-panel {
  padding-block: 0.56rem;
}

body.keyboard-open:not([data-active-tool="calc"]) #primary-result {
  font-size: clamp(1.5rem, 5.5vw, 2rem);
}

body.keyboard-open:not([data-active-tool="calc"]) .secondary-results {
  display: none;
}

body.keyboard-open:not([data-active-tool="calc"]) .display-actions {
  margin-top: 0.45rem;
}

body.keyboard-open:not([data-active-tool="calc"]) .display-actions button {
  min-height: 2.1rem;
}

.top-bar,
.install-help,
.workspace-shell,
.tool-menu-sheet,
.keyboard-dock {
  background: var(--panel);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  backdrop-filter: blur(16px);
}

.top-bar {
  min-height: 2.25rem;
  border-radius: 0;
  border-width: 0 0 1px;
  box-shadow: none;
  backdrop-filter: none;
  background: transparent;
  padding: 0 0.15rem 0.18rem;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 0.35rem;
}

.top-button {
  min-height: 1.95rem;
  padding: 0.3rem 0.6rem;
  border-radius: 999px;
}

.brand-lockup {
  min-width: 0;
}

h1,
h2,
h3,
p {
  margin: 0;
}

h1 {
  font-size: clamp(1rem, 3vw, 1.2rem);
  line-height: 1;
  letter-spacing: -0.03em;
}

h2 {
  font-size: 1rem;
}

h3 {
  font-size: 0.9rem;
}

.brand-subtitle,
.tool-group-label,
.field span,
.secondary-results,
.list-meta,
.inline-help p,
.save-panel summary,
.display-mode,
.keyboard-target {
  color: var(--muted);
}

.brand-subtitle {
  display: none;
}

.top-actions,
.display-meta,
.display-actions,
.tool-window-head,
.panel-block-head,
.tool-menu-head,
.keyboard-bar,
.list-title,
.list-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.55rem;
}

.status-pill {
  display: inline-flex;
  align-items: center;
  min-height: 1.9rem;
  padding: 0.2rem 0.7rem;
  border-radius: 999px;
  background: color-mix(in srgb, var(--panel-soft) 90%, transparent);
  border: 1px solid var(--line);
  color: var(--text);
  font-size: 0.77rem;
  font-weight: 700;
}

#offline-badge {
  display: none;
}

.ghost-button {
  background: transparent;
  color: var(--text);
  border-color: var(--line);
}

.accent-button {
  background: linear-gradient(180deg, var(--accent-strong), var(--accent));
}

.install-help {
  border-radius: 0.85rem;
  padding: 0.34rem 0.55rem;
  display: flex;
  justify-content: space-between;
  gap: 0.45rem;
  align-items: center;
  font-size: 0.78rem;
}

.install-help h2 {
  display: none;
}

.install-help p {
  margin-top: 0;
  color: var(--muted);
  line-height: 1.2;
}

.workspace-shell {
  flex: 1;
  min-height: 0;
  display: grid;
  grid-template-rows: auto 1fr;
  gap: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.display-panel {
  border-radius: 0;
  padding: 0.62rem 0.72rem 0.5rem;
  overflow: hidden;
  background: transparent;
  border: 0;
  box-shadow: none;
  backdrop-filter: none;
  border-bottom: 1px solid var(--line);
}

.display-mode {
  font-size: 0.82rem;
  font-weight: 700;
}

#primary-result {
  display: block;
  margin-top: 0.32rem;
  font-size: clamp(1.85rem, 7vw, 2.6rem);
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.05em;
  overflow-wrap: anywhere;
}

.secondary-results {
  display: grid;
  gap: 0.12rem;
  margin-top: 0.35rem;
  font-size: 0.9rem;
}

.display-actions {
  margin-top: 0.46rem;
}

.display-actions button {
  flex: 1 1 0;
  min-height: 2.08rem;
}

.tool-window {
  min-height: 0;
  border-radius: 0;
  padding: 0.52rem 0.72rem 0.64rem;
  display: grid;
  grid-template-rows: auto 1fr;
  gap: 0.42rem;
  overflow: hidden;
  background: transparent;
  border: 0;
  box-shadow: none;
  backdrop-filter: none;
}

.tool-window-head {
  padding-bottom: 0.34rem;
  border-bottom: 1px solid var(--line);
}

.tool-group-label {
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.tool-window-body {
  min-height: 0;
  overflow: hidden;
  position: relative;
  display: grid;
}

.tool-view {
  height: 100%;
  display: grid;
  gap: 0.42rem;
  align-content: start;
  min-height: 0;
}

.tool-view[hidden] {
  display: none;
}

.tool-view:not([data-tool-view="calc"]):not([data-tool-view="saved"]) {
  grid-template-rows: auto minmax(0, 1fr);
}

.tool-view[data-tool-view="calc"] {
  grid-template-rows: auto auto minmax(0, 1fr);
}

.tool-view[data-tool-view="saved"] {
  grid-template-rows: minmax(0, 1fr);
}

.field-grid {
  display: grid;
  gap: 0.42rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.field-grid.two-up {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.field {
  display: grid;
  gap: 0.22rem;
}

.field span {
  font-size: 0.68rem;
  font-weight: 700;
}

.tool-form {
  display: grid;
  gap: 0.42rem;
  align-content: start;
}

.compact-form button {
  min-height: 2.08rem;
}

.calc-support-grid,
.saved-grid {
  display: grid;
  gap: 0.42rem;
  min-height: 0;
  overflow: hidden;
}

.saved-grid {
  grid-template-rows: repeat(2, minmax(0, 1fr));
}

.panel-block {
  min-height: 0;
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--panel-soft) 90%, transparent);
  padding: 0.48rem;
  display: grid;
  gap: 0.34rem;
  grid-template-rows: auto minmax(0, 1fr);
}

.tool-output {
  display: grid;
  gap: 0.3rem;
  min-height: 0;
  align-content: start;
  overflow: hidden;
}

.tool-output[hidden] {
  display: none;
}

.result-grid {
  display: grid;
  gap: 0.3rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.result-row {
  display: grid;
  gap: 0.18rem;
  padding: 0.42rem 0.5rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--panel-strong) 92%, transparent);
}

.result-row span:first-child {
  color: var(--muted);
  font-size: 0.66rem;
}

.result-row span:last-child {
  font-weight: 700;
  line-height: 1.2;
  font-size: 0.88rem;
}

.inline-help,
.save-panel {
  border-top: 1px solid var(--line);
  padding-top: 0.42rem;
}

.inline-help summary,
.save-panel summary {
  cursor: pointer;
  font-weight: 700;
}

.inline-help p {
  margin-top: 0.25rem;
  font-size: 0.74rem;
}

.save-panel[open] .field-grid {
  margin-top: 0.42rem;
}

.list-stack {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 0.34rem;
}

.compact-list {
  align-content: start;
  min-height: 0;
  overflow: hidden;
}

.list-item {
  display: grid;
  gap: 0.22rem;
  padding: 0.42rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--panel-strong) 92%, transparent);
}

.list-title strong {
  font-size: 0.8rem;
}

.list-actions button {
  min-height: 1.8rem;
  padding: 0.28rem 0.52rem;
}

.empty-state {
  padding: 0.8rem;
  border-radius: var(--radius-sm);
  border: 1px dashed var(--line);
  color: var(--muted);
}

.tool-menu {
  position: fixed;
  inset: 0;
  z-index: 15;
  background: rgba(8, 10, 14, 0.48);
  padding:
    calc(0.85rem + env(safe-area-inset-top))
    0.85rem
    calc(0.85rem + env(safe-area-inset-bottom));
}

.tool-menu[hidden] {
  display: none;
}

.tool-menu-sheet {
  width: min(100%, 37rem);
  max-height: 100%;
  margin: 0 auto;
  border-radius: var(--radius-lg);
  padding: 0.75rem;
  display: grid;
  gap: 0.7rem;
}

.tool-menu-grid {
  display: grid;
  gap: 0.7rem;
}

.tool-menu-group {
  display: grid;
  gap: 0.45rem;
}

.tool-menu-item {
  justify-content: flex-start;
  background: color-mix(in srgb, var(--panel-soft) 92%, transparent);
  color: var(--text);
  border-color: var(--line);
}

.tool-menu-item.is-active {
  background: color-mix(in srgb, var(--accent) 24%, var(--panel-soft));
  border-color: color-mix(in srgb, var(--accent) 55%, var(--line));
}

.keyboard-dock {
  position: fixed;
  left: 50%;
  transform: translateX(-50%);
  bottom: 0;
  width: min(100%, 37rem);
  padding:
    0.38rem
    0.65rem
    calc(0.56rem + env(safe-area-inset-bottom));
  border-radius: 1.3rem 1.3rem 0 0;
  z-index: 12;
}

.keyboard-dock[hidden] {
  display: none;
}

.keyboard-bar {
  margin-bottom: 0.25rem;
}

.keyboard-target {
  font-size: 0.85rem;
  font-weight: 700;
}

.keyboard-close {
  min-height: 2rem;
  padding: 0.28rem 0.68rem;
}

.fraction-strip {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 0.24rem;
  margin-bottom: 0.24rem;
}

.keypad {
  display: grid;
  gap: 0.24rem;
}

.keypad button[hidden],
.fraction-strip button[hidden] {
  display: none;
}

.keypad-main {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.keypad button,
.fraction-strip button {
  min-height: 2.08rem;
  padding: 0.28rem 0.2rem;
  border-color: var(--line);
}

.fraction-strip button {
  min-height: 1.52rem;
  font-size: 0.7rem;
}

.key-num {
  background: color-mix(in srgb, var(--panel-strong) 92%, transparent);
  color: var(--text);
}

.key-op,
.key-unit {
  background: color-mix(in srgb, var(--accent) 18%, var(--panel-soft));
  color: var(--text);
}

.key-util,
.key-frac {
  background: color-mix(in srgb, var(--panel-soft) 94%, transparent);
  color: var(--text);
}

@media (max-height: 820px) {
  :root {
    --keyboard-height: 13.7rem;
  }

  .app-shell {
    gap: 0.26rem;
    padding-inline: 0.6rem;
  }

  .top-bar,
  .keyboard-dock {
    padding-inline: 0.62rem;
  }

  .display-panel,
  .tool-window {
    padding-block: 0.48rem;
  }

  #primary-result {
    font-size: clamp(1.45rem, 5.9vw, 2rem);
  }

  .secondary-results {
    font-size: 0.76rem;
    gap: 0.08rem;
  }

  .display-actions button,
  .compact-form button,
  .top-button,
  .keyboard-close {
    min-height: 1.92rem;
  }

  input,
  button {
    font-size: 0.9rem;
  }

  .field span,
  .tool-group-label {
    font-size: 0.64rem;
  }

  .keypad button {
    min-height: 1.86rem;
    padding: 0.24rem 0.18rem;
  }

  .fraction-strip button {
    min-height: 1.4rem;
    font-size: 0.66rem;
  }
}

.error-box {
  padding: 0.75rem;
  border-radius: var(--radius-sm);
  border: 1px solid color-mix(in srgb, var(--danger) 46%, transparent);
  background: color-mix(in srgb, var(--danger) 10%, transparent);
  color: var(--text);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

@media (min-width: 36rem) {
  .calc-support-grid,
  .tool-menu-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .saved-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    grid-template-rows: none;
  }

  .field-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}