/* Using a modern font stack */
.calculator-container {
    font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans', sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol', 'Noto Color Emoji';
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Main calculator container */
.calculator-container {
    width: 100%;
    background-color: white;
    padding: 2rem;
    box-sizing: border-box; /* Ensures padding is contained within the width */
}

/* Heading */
.calculator-container h1 {
    font-size: 1.875rem; /* text-3xl */
    font-weight: 800; /* font-extrabold */
    color: #111827; /* text-gray-900 */
    text-align: center;
    margin-top: 0;
    margin-bottom: 2rem;
}

/* Grid layout for inputs */
.calculator-container .input-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.25rem; /* gap-5 */
    margin-bottom: 1.25rem;
}

.calculator-container .input-group {
    display: flex;
    flex-direction: column;
}

.calculator-container .input-group label {
    font-size: 0.875rem; /* text-sm */
    font-weight: 500;
    color: #4b5563; /* text-gray-700 */
    margin-bottom: 0.25rem; /* mb-1 */
}

.calculator-container .input-group input {
    width: 100%;
    box-sizing: border-box; /* Ensures padding doesn't affect width */
    border: 1px solid #d1d5db; /* border-gray-300 */
    font-size: 1.125rem; /* text-lg */
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
    border-radius: 0.375rem; /* Added for consistency */
}

.calculator-container .input-group input:focus {
    outline: none;
    border-color: #3b82f6; /* focus:border-blue-500 */
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.5); /* focus:ring-blue-500 */
}

.calculator-container #error-message {
    color: #dc2626; /* text-red-600 */
    font-size: 0.875rem; /* text-sm */
    font-weight: 600; /* font-semibold */
    background-color: #fee2e2; /* bg-red-100 */
    padding: 0.5rem; /* p-2 */
    border-radius: 0.375rem;
}

.calculator-container .hidden {
    display: none;
}

/* Results Section */
.calculator-container #results-section {
    padding-top: 1rem; /* pt-4 */
    border-top: 1px solid #e5e7eb; /* border-t border-gray-200 */
}

.calculator-container .results-grid {
     display: grid;
    grid-template-columns: 1fr;
    gap: 1rem; /* gap-4 */
}

@media (min-width: 640px) {
    .calculator-container .results-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.calculator-container .result-item {
    padding: 0.75rem; /* p-3 */
    text-align: center;
    border-radius: 0.375rem;
}

.calculator-container .result-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: #374151; /* text-gray-700 */
}

.calculator-container .result-value {
    display: block;
    font-size: 1.25rem; /* text-xl */
    font-weight: 700; /* font-bold */
    color: #111827; /* text-gray-900 */
}

.calculator-container .opacity-50 {
    opacity: 0.5;
}