:root {
    --primary-color: #0056b3;
    --bg-color: #f4f7f6;
    --card-bg: #ffffff;
    --text-color: #333333;
    --border-radius: 12px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    padding: 0;
    line-height: 1.5;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
}

header {
    background: linear-gradient(135deg, #1e3c72, #2a5298);
    color: white;
    padding: 25px 0;
    text-align: center;
    position: relative;
}

.header-content h1 {
    margin: 0 0 8px 0;
    font-size: 1.7rem;
}

.header-content p {
    font-size: 0.9rem;
    opacity: 0.9;
    max-width: 700px;
    margin: 0 auto 10px auto;
    padding: 0 15px;
}

.lang-selector {
    position: absolute;
    top: 15px;
    right: 15px;
}

.lang-selector select {
    padding: 5px 8px;
    border-radius: 6px;
    border: none;
    background: white;
    font-weight: bold;
    cursor: pointer;
}

.card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 20px;
    margin-top: 15px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.03);
}

.card h2 {
    margin-top: 0;
    font-size: 1.2rem;
    color: #1e3c72;
    border-bottom: 2px solid #f0f0f0;
    padding-bottom: 8px;
}

.scenario-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 12px;
    margin-top: 12px;
}

.scenario-btn {
    background: #f8f9fa;
    border: 2px solid #e9ecef;
    border-radius: var(--border-radius);
    padding: 12px;
    font-size: 0.95rem;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    font-weight: 600;
}

.scenario-btn .icon {
    font-size: 1.8rem;
}

.scenario-btn:hover, .scenario-btn.active {
    border-color: var(--primary-color);
    background: #eef5ff;
    color: var(--primary-color);
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 6px;
    font-weight: 600;
}

.form-group select {
    width: 100%;
    padding: 8px;
    border-radius: 6px;
    border: 1px solid #ced4da;
    font-size: 0.95rem;
}

/* Блок додавання власних приладів */
.add-appliance-box {
    background: #f8f9fa;
    padding: 15px;
    border-radius: 8px;
    border: 1px dashed #cbd5e1;
    margin-bottom: 15px;
}

.add-appliance-box h3 {
    margin: 0 0 10px 0;
    font-size: 0.95rem;
    color: #334155;
}

.add-row {
    display: grid;
    grid-template-columns: 2fr 1fr 100px auto;
    gap: 8px;
}

@media(max-width: 650px) {
    .add-row {
        grid-template-columns: 1fr;
    }
}

.add-row input, .add-row select {
    padding: 8px;
    border-radius: 6px;
    border: 1px solid #ced4da;
    font-size: 0.9rem;
}

.btn-add {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 8px 16px;
    border-radius: 6px;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-add:hover {
    background: #004085;
}

.appliances-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 10px;
}

.appliance-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: #fdfdfd;
    border: 1px solid #e2e8f0;
    padding: 8px 12px;
    border-radius: 6px;
}

.appliance-item label {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    font-size: 0.9rem;
    margin: 0;
    flex-grow: 1;
}

.appliance-item input[type="checkbox"] {
    width: 16px;
    height: 16px;
    cursor: pointer;
}

.btn-delete {
    background: none;
    border: none;
    color: #e53e3e;
    cursor: pointer;
    font-size: 1.1rem;
    padding: 2px 6px;
    border-radius: 4px;
}

.btn-delete:hover {
    background: #fff5f5;
}

.results-card {
    background: #f8f9fa;
    border: 1px solid #dee2e6;
}

.result-metrics {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin-bottom: 20px;
}

@media(max-width: 600px) {
    .result-metrics {
        grid-template-columns: 1fr;
    }
    .lang-selector {
        position: static;
        margin-top: 10px;
    }
}

.metric-box {
    background: white;
    padding: 12px;
    border-radius: 6px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.03);
    text-align: center;
}

.metric-box span {
    display: block;
    font-size: 0.8rem;
    color: #666;
    margin-bottom: 4px;
}

.metric-box strong {
    font-size: 1.3rem;
    color: var(--primary-color);
}

.fuel-recommendations {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 12px;
    margin-top: 12px;
}

.fuel-card {
    background: white;
    border-radius: 6px;
    padding: 12px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.03);
    border-left: 4px solid var(--primary-color);
}

.fuel-card h4 {
    margin: 0 0 6px 0;
    font-size: 0.95rem;
}

.fuel-card p {
    margin: 0;
    font-size: 0.85rem;
    color: #555;
}

/* Стилі для підвалу (Footer) */
.site-footer {
    background-color: #ffffff;
    border-top: 1px solid #e2e8f0;
    margin-top: 40px;
    padding: 30px 0;
    text-align: center;
    color: #475569;
    box-shadow: 0 -4px 15px rgba(0,0,0,0.02);
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
}

.feedback-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background-color: #1877F2;
    color: #ffffff;
    padding: 12px 24px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    transition: background-color 0.3s, transform 0.2s;
    box-shadow: 0 4px 6px rgba(24, 119, 242, 0.2);
}

.feedback-link:hover {
    background-color: #166fe5;
    transform: translateY(-2px);
    color: #ffffff;
}

.visitor-counter {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.9rem;
    font-weight: 600;
    background: #f8f9fa;
    padding: 8px 16px;
    border-radius: 20px;
    border: 1px solid #e2e8f0;
}

.visitor-counter img {
    border-radius: 4px;
}

.author-info {
    font-size: 0.9rem;
    color: #64748b;
    margin-top: 5px;
}

.author-info strong {
    color: var(--primary-color);
    font-weight: 700;
    letter-spacing: 0.5px;
}