:root {
    --primary: #007bff;
    --primary-dark: #0056b3;
    --secondary: #6c757d;
    --success: #28a745;
    --background: #f4f6f9;
    --surface: #ffffff;
    --text: #333333;
    --text-light: #666666;
    --border: #dee2e6;
    --shadow: 0 4px 6px rgba(0,0,0,0.05);
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--background);
    color: var(--text);
    margin: 0;
    padding: 2rem;
    line-height: 1.5;
}

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

header {
    text-align: center;
    margin-bottom: 3rem;
}

header h1 {
    font-size: 2.5rem;
    color: var(--primary-dark);
    margin-bottom: 0.5rem;
}

header p {
    color: var(--text-light);
    font-size: 1.1rem;
}

.disclaimer {
    font-size: 0.85rem;
    color: var(--text-light);
    margin-top: 0.5rem;
    opacity: 0.8;
}

.main-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 2rem;
}

@media (max-width: 768px) {
    .main-grid {
        grid-template-columns: 1fr;
    }
}

.card {
    background: var(--surface);
    border-radius: 12px;
    padding: 2rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
}

.card h2 {
    margin-top: 0;
    color: var(--primary-dark);
    font-size: 1.5rem;
    border-bottom: 2px solid var(--background);
    padding-bottom: 1rem;
    margin-bottom: 1.5rem;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.add-resource {
    display: flex;
    gap: 10px;
}

select {
    flex: 1;
    padding: 0.75rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 1rem;
}

.btn-add {
    background: var(--primary);
    color: white;
    border: none;
    padding: 0 1.5rem;
    border-radius: 6px;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-add:hover {
    background: var(--primary-dark);
}

.resource-list {
    margin: 1.5rem 0;
    max-height: 200px;
    overflow-y: auto;
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 0.5rem;
    background: #fafafa;
}

.resource-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem;
    border-bottom: 1px solid var(--border);
    background: white;
    margin-bottom: 4px;
    border-radius: 4px;
}

.resource-item:last-child {
    margin-bottom: 0;
}

.btn-remove {
    background: #ff4d4d;
    color: white;
    border: none;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
}

.stats {
    border-top: 2px solid var(--background);
    padding-top: 1rem;
}

.stat-row {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
}

.stat-row.highlight {
    font-weight: 700;
    color: var(--primary-dark);
    font-size: 1.1rem;
    margin-top: 1rem;
}

.result-card {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    text-align: center;
}

.result-card h2 {
    color: white;
    border-bottom-color: rgba(255,255,255,0.2);
}

.final-result {
    font-size: 1.5rem;
    font-weight: 500;
}

.final-result .value {
    display: block;
    font-size: 3.5rem;
    font-weight: 700;
    margin-top: 0.5rem;
}

.settings-section {
    margin-top: 3rem;
    text-align: center;
}

.btn-text {
    background: none;
    border: none;
    color: var(--text-light);
    text-decoration: underline;
    cursor: pointer;
    font-size: 0.9rem;
}

.settings-panel {
    margin-top: 1.5rem;
    background: var(--surface);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    text-align: left;
}

.settings-panel.hidden {
    display: none;
}

.settings-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

.setting-item input {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid var(--border);
    border-radius: 6px;
}

.btn-secondary {
    background: var(--secondary);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    cursor: pointer;
}