:root {
    --primary-color: #2e7d32;
    --primary-light: #e8f5e9;
    --secondary-color: #1565c0;
    --accent-color: #f57c00;
    --text-color: #333;
    --bg-color: #f5f7fa;
    --card-bg: #ffffff;
    --border-color: #e0e0e0;
}

*, *::before, *::after {
    box-sizing: border-box;
}

body {
    font-family: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    padding: 16px;
    line-height: 1.6;
}

.container {
    max-width: 960px;
    margin: 0 auto;
}

header {
    text-align: center;
    margin-bottom: 40px;
}

header h1 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

header p {
    color: #666;
    margin: 0;
}

.card {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 24px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    border: 1px solid var(--border-color);
}

.calculator-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    margin-bottom: 24px;
}

@media (min-width: 900px) {
    .calculator-grid {
        grid-template-columns: 350px 1fr;
    }
}

/* Input Section */
.input-section h2 {
    margin-top: 0;
    margin-bottom: 20px;
    font-size: 1.2rem;
    color: var(--text-color);
    border-bottom: 2px solid var(--primary-light);
    padding-bottom: 10px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: bold;
    font-size: 0.9rem;
    color: #555;
}

.input-wrapper {
    display: flex;
    align-items: center;
    background: #fff;
    border: 1px solid #ccc;
    border-radius: 6px;
    padding: 0 12px;
    transition: border-color 0.3s;
}

.input-wrapper:focus-within {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px var(--primary-light);
}

.input-wrapper input {
    border: none;
    outline: none;
    width: 100%;
    padding: 10px 0;
    font-size: 1rem;
    text-align: right;
}

.unit {
    margin-left: 8px;
    color: #777;
    font-size: 0.9rem;
}

.range-slider {
    width: 100%;
    margin-top: 10px;
    cursor: pointer;
}

/* Result Section */
.summary-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
    margin-bottom: 24px;
}

.summary-card {
    background: var(--card-bg);
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    text-align: center;
    border-top: 4px solid #ccc;
}

.summary-card h3 {
    margin: 0 0 10px 0;
    font-size: 0.9rem;
    color: #666;
}

.summary-card p {
    margin: 0;
    font-size: 1.5rem;
    font-weight: bold;
}

.summary-card.total {
    border-top-color: var(--primary-color);
}
.summary-card.total p {
    color: var(--primary-color);
}

.summary-card.principal {
    border-top-color: var(--secondary-color);
}
.summary-card.principal p {
    color: var(--secondary-color);
}

.summary-card.interest {
    border-top-color: var(--accent-color);
}
.summary-card.interest p {
    color: var(--accent-color);
}

.chart-container {
    position: relative;
    height: 400px;
    width: 100%;
}

/* Table Section */
.table-section h2 {
    margin-top: 0;
    font-size: 1.2rem;
    margin-bottom: 20px;
}

.table-wrapper {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9rem;
}

th, td {
    padding: 12px;
    text-align: right;
    border-bottom: 1px solid #eee;
}

th {
    background-color: #f9f9f9;
    font-weight: bold;
    color: #555;
    white-space: nowrap;
}

th:first-child, td:first-child {
    text-align: center;
}

tr:hover {
    background-color: #f5f5f5;
}