:root {
  /* SEA MOVES palette — sampled from site screenshot */
  --color-primary: #1b4b3a;       /* deep forest green — header, buttons, footer */
  --color-primary-dark: #123527;  /* darker shade for hover states */
  --color-accent: #3aae4a;        /* bright kelly green — logo accent, highlights */
  --color-background: #ffffff;
  --color-surface: #f6f7f6;       /* very light gray-green — card backgrounds */
  --color-text: #333333;
  --color-text-muted: #5c5c5c;
  --color-text-on-dark: #ffffff;
  --color-border: #e0e0e0;

  --font-base: 'Helvetica Neue', Arial, sans-serif;
  --radius: 8px;
  --spacing-unit: 1rem;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: var(--font-base);
  color: var(--color-text);
  background: var(--color-background);
  line-height: 1.5;
}

#calculator-root {
  max-width: 480px;
  margin: 2rem auto;
  padding: 2rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}

.calc-title {
  color: var(--color-primary);
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.calc-field {
  margin-bottom: 1rem;
}

.calc-field label {
  display: block;
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin-bottom: 0.25rem;
}

.calc-field input,
.calc-field select {
  width: 100%;
  padding: 0.6rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font-size: 1rem;
  color: var(--color-text);
}

.calc-field input:focus,
.calc-field select:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 2px rgba(58, 174, 74, 0.2);
}

.calc-submit {
  background: var(--color-primary);
  color: var(--color-text-on-dark);
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s ease;
}

.calc-submit:hover {
  background: var(--color-primary-dark);
}

.calc-results {
  margin-top: 1.5rem;
  padding: 1rem;
  background: #fff;
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius);
}

.calc-results .result-value {
  color: var(--color-primary);
  font-weight: 700;
  font-size: 1.25rem;
}


.slider-value {
  color: var(--color-primary);
  font-weight: 700;
}

input[type="range"] {
  width: 100%;
  accent-color: var(--color-accent);
  margin-top: 0.5rem;
}

.result-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--color-border);
}

.result-row:last-child {
  border-bottom: none;
}

.calc-output-title {
  color: var(--color-primary);
  font-size: 1.125rem;
  font-weight: 700;
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
}

.calc-reset {
  background: transparent;
  color: var(--color-primary);
  border: 1px solid var(--color-primary);
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease;
}

.calc-reset:hover {
  background: var(--color-primary);
  color: var(--color-text-on-dark);
}

@media (max-width: 480px) {
  #calculator-root {
    margin: 1rem;
    padding: 1.25rem;
  }

  .calc-title {
    font-size: 1.25rem;
  }

  .result-row {
    font-size: 0.9rem;
  }

  .calc-reset,
  .calc-submit {
    width: 100%;
    padding: 0.75rem;
  }
}

input[type="range"] {
  height: 44px; /* larger tap target for the slider track, thumb sizing is browser-default */
}