/* --- Global Styles --- */
@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@400;700&display=swap');

:root {
    --bg-color: #f0f4f8;
    --card-bg-color: rgba(255, 255, 255, 0.6);
    --text-color: #333;
    --header-color: #2c3e50;
    --accent-color: #4a90e2;
    --border-color: rgba(255, 255, 255, 0.8);
    --shadow-color: rgba(0, 0, 0, 0.1);
}

.oil-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* --- Header --- */
.oil-main-header {
    text-align: center;
    margin-bottom: 40px;
    padding: 20px;
}

.oil-main-header h1 {
    font-size: 2.8rem;
    color: var(--header-color);
    margin-bottom: 10px;
    font-weight: 700;
}

.oil-subtitle {
    font-size: 1.2rem;
    color: #555;
}

/* --- Card Styles (Glassmorphism) --- */
.oil-card {
    background: var(--card-bg-color);
    border-radius: 15px;
    padding: 25px;
    margin-bottom: 30px;
    border: 1px solid var(--border-color);
    box-shadow: 0 8px 32px 0 var(--shadow-color);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    transition: transform 0.3s ease;
}

.oil-card:hover {
    transform: translateY(-5px);
}

h2 {
    font-size: 2rem;
    color: var(--header-color);
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--accent-color);
    font-weight: 700;
}

h3 {
    font-size: 1.5rem;
    color: var(--header-color);
    margin-bottom: 15px;
}

h2 .fas, h3 .fas {
    margin-right: 10px;
    color: var(--accent-color);
}

/* --- Grid Layout --- */
.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
}

/* --- Oil Guide Specific Styles --- */
.oil-grid {
    display: grid;
    gap: 30px;
}

/* --- Responsive Design for Grid --- */


.oil-card-large {
    background: var(--card-bg-color);
    border-radius: 20px;
    border: 1px solid var(--border-color);
    box-shadow: 0 8px 32px 0 var(--shadow-color);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.oil-card-large:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 40px 0 rgba(0, 0, 0, 0.15);
}

.oil-card-header {
    padding: 20px 20px 0 20px;
    text-align: center;
    background-color: rgba(255, 255, 255, 0.3);
}

.oil-card-header h3 {
    margin: 0;
    font-size: 1.8rem;
    color: var(--header-color);
}

.oil-icon {
    font-size: 3.5rem;
    display: block;
    margin-bottom: 10px;
}

.oil-card-body {
    padding: 0 25px 25px 25px;
    flex-grow: 1;
}

.oil-card-body h4 {
    font-size: 1.2rem;
    color: var(--accent-color);
    margin-top: 20px;
    margin-bottom: 10px;
    font-weight: 700;
    border-left: 4px solid var(--accent-color);
    padding-left: 8px;
}

.oil-card-body ul {
    list-style: none;
    padding-left: 10px;
}

.oil-card-body ul li {
    margin-bottom: 8px;
    position: relative;
    padding-left: 20px;
}

.oil-card-body ul li::before {
    content: '✅';
    position: absolute;
    left: 0;
    top: 0;
    color: var(--accent-color);
}

.oil-card-body p strong {
    color: #d63384; /* A highlight color */
}

/* --- Table Styles --- */
.table-container {
    overflow-x: auto;
    margin-top: 20px;
}

table {
    width: 100%;
    border-collapse: collapse;
    text-align: center;
}

th, td {
    padding: 12px 15px;
    border: 1px solid rgba(0,0,0,0.05);
}

thead {
    background-color: var(--accent-color);
    color: white;
    font-weight: bold;
}

thead th {
    font-size: 1.1rem;
}

tbody tr {
    transition: background-color 0.2s ease;
}

tbody tr:nth-of-type(even) {
    background-color: rgba(255, 255, 255, 0.5);
}

tbody tr:hover {
    background-color: rgba(74, 144, 226, 0.2);
}

.oil-emoji {
    font-size: 1.5rem;
    margin-right: 10px;
    vertical-align: middle;
}

td strong {
    color: var(--header-color);
}

.table-note {
    margin-top: 15px;
    font-size: 0.9rem;
    text-align: right;
    color: #666;
}

/* --- Checklist Styles --- */
.checklist {
    list-style: none;
    padding-left: 0;
}

.checklist li {
    font-size: 1.1rem;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
}

.checklist .fas {
    color: #27ae60;
    font-size: 1.5rem;
    margin-right: 15px;
}

/* --- References Styles --- */
.references-list {
    background: rgba(0,0,0,0.03);
    border-radius: 10px;
    padding: 20px;
    height: 250px;
    overflow-y: auto;
    font-size: 0.9rem;
}

.references-list ul {
    list-style-type: decimal;
    padding-left: 20px;
    margin: 0;
}

.references-list li {
    margin-bottom: 8px;
    color: #555;
}

/* --- Insight/Nuance Box --- */
.insight-box {
    background-color: rgba(74, 144, 226, 0.1);
    border-left: 5px solid var(--accent-color);
    padding: 15px 20px;
    margin: 20px 0;
    border-radius: 0 8px 8px 0;
}

.insight-box p {
    margin: 0;
    font-size: 1rem;
    color: #2c3e50;
}

.insight-box strong {
    color: var(--accent-color);
    font-weight: 700;
}

/* --- Responsive Design --- */
@media (max-width: 768px) {
    body {
        padding: 10px;
    }
    
    .oil-container {
        padding: 10px;
    }

    .oil-main-header h1 {
        font-size: 2.2rem;
    }

    h2 {
        font-size: 1.6rem;
    }

    h3 {
        font-size: 1.3rem;
    }

    .grid-container {
        grid-template-columns: 1fr;
    }

    .oil-grid {
        grid-template-columns: 1fr;
    }
}