body {
    font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    min-height: 100vh;
    margin: 0;
    padding: 20px;
    box-sizing: border-box;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: #fff;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.05);
}

h1 {
    text-align: center;
    color: #2c3e50;
    margin-bottom: 30px;
}

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

label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}

input[type="number"] {
    width: 100%;
    padding: 10px;
    font-size: 16px;
    border: 1px solid #ddd;
    border-radius: 4px;
    box-sizing: border-box;
    /* Ensures padding doesn't affect width */
}

button {
    display: block;
    width: 100%;
    padding: 12px;
    background-color: #3498db;
    color: #fff;
    border: none;
    border-radius: 4px;
    font-size: 18px;
    cursor: pointer;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #2980b9;
}

.result-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 30px;
}

.result-table th,
.result-table td {
    padding: 12px 15px;
    border-bottom: 1px solid #eee;
    text-align: left;
}

.result-table th {
    background-color: #f8f9fa;
    font-weight: bold;
    width: 40%;
}

.result-table td {
    text-align: right;
}

.result-table tr:last-child {
    border-bottom: 2px solid #2c3e50;
    font-weight: bold;
    font-size: 1.2em;
    background-color: #f0f7fb;
}

.note {
    font-size: 0.9em;
    color: #666;
    margin-top: 20px;
}

/* Index Page Styles */
.tool-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.tool-card {
    display: block;
    background: #fff;
    padding: 20px;
    border-radius: 8px;
    text-decoration: none;
    color: #333;
    border: 1px solid #eee;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
}

.tool-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    border-color: #3498db;
}

.tool-card.disabled {
    opacity: 0.6;
    cursor: default;
    background: #f9f9f9;
}

.tool-card.disabled:hover {
    transform: none;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    border-color: #eee;
}

.tool-card h2 {
    margin-top: 0;
    margin-bottom: 10px;
    font-size: 1.25em;
    color: #2c3e50;
    text-align: left;
    border-bottom: 1px solid #f0f0f0;
    padding-bottom: 10px;
}

.tool-card p {
    margin: 0;
    font-size: 0.95em;
    color: #666;
}

/* Navigation Links */
.nav-link {
    display: inline-block;
    margin-bottom: 20px;
    color: #3498db;
    text-decoration: none;
    font-weight: bold;
}

.nav-link:hover {
    text-decoration: underline;
}