* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

.calc-container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 auto;
}

.calc-header {
    text-align: center;
    margin-bottom: 30px;
    padding: 30px 20px;
    background: linear-gradient(135deg, #249749 0%, #002811 100%);
    border-radius: 12px;
    color: white;
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.3);
}

.calc-header h2 {
    font-size: 2.2rem;
    margin-bottom: 10px;
    font-weight: 700;
}

.calc-header p {
    font-size: 1.05rem;
    opacity: 0.95;
}

.tab-navigation {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 25px;
    background: white;
    padding: 15px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
}

.tab-ibtn {
    flex: 1;
    min-width: 140px;
    padding: 12px 16px;
    background: #f7fafc;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.95rem;
    font-weight: 600;
    color: #4a5568;
    text-align: center;
}

.tab-ibtn:hover {
    background: #edf2f7;
    border-color: #cbd5e0;
    transform: translateY(-2px);
}

.tab-ibtn.active {
    background: linear-gradient(135deg, #249749 0%, #002811 100%);
    color: white;
    border-color: #249749;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.calc-panel {
    display: none;
    background: white;
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    margin-bottom: 20px;
}

.calc-panel.active {
    display: block;
    animation: fadeIn 0.3s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #2d3748;
    font-size: 0.95rem;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.3s ease;
    background: #f7fafc;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #249749;
    background: white;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.calc-ibutton {
    width: 100%;
    padding: 14px 24px;
    background: linear-gradient(135deg, #249749 0%, #002811 100%);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.05rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-top: 15px;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

.calc-ibutton:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
}

.calc-ibutton:active {
    transform: translateY(0);
}

.result-box {
    margin-top: 25px;
    padding: 25px;
    background: linear-gradient(135deg, #f0fff4 0%, #e6fffa 100%);
    border-left: 5px solid #48bb78;
    border-radius: 8px;
    display: none;
}

.result-box.show {
    display: block;
    animation: slideIn 0.4s ease;
}

@keyframes slideIn {
    from { opacity: 0; transform: translateX(-20px); }
    to { opacity: 1; transform: translateX(0); }
}

.result-box h3 {
    color: #22543d;
    margin-bottom: 15px;
    font-size: 1.3rem;
}

.result-item {
    padding: 12px 0;
    border-bottom: 1px solid #c6f6d5;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.result-item:last-child {
    border-bottom: none;
}

.result-label {
    font-weight: 600;
    color: #2d3748;
}

.result-value {
    font-size: 1.2rem;
    font-weight: 700;
    color: #2f855a;
}

.info-box {
    background: #ebf8ff;
    border-left: 4px solid #4299e1;
    padding: 15px;
    margin: 20px 0;
    border-radius: 6px;
    font-size: 0.9rem;
    color: #2c5282;
}

.unit-toggle {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    justify-content: center;
}

.unit-ibtn {
    padding: 8px 20px;
    background: #f7fafc;
    border: 2px solid #e2e8f0;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
}

.unit-ibtn.active {
    background: #249749;
    color: white;
    border-color: #249749;
}

.grid-type-selector {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin: 15px 0;
}

.grid-type-ibtn {
    padding: 12px;
    background: #f7fafc;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    cursor: pointer;
    text-align: center;
    transition: all 0.3s ease;
    font-weight: 600;
}

.grid-type-ibtn:hover {
    border-color: #cbd5e0;
}

.grid-type-ibtn.active {
    background: #249749;
    color: white;
    border-color: #249749;
}

.seo-intro {
    max-width: 1000px;
    margin: 0 auto;
    padding: 20px;
    background: white;
    border-radius: 10px;
    margin-bottom: 20px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.how-to-guide {
    max-width: 1000px;
    margin: 20px auto;
    padding: 30px;
    background: white;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.how-to-use {
    color: #2d3748;
    margin-bottom: 20px;
    font-size: 1.8rem;
}

.how-to-step {
    color: 2d3748;
    margin: 20px 0 10px 0;
    font-size: 1.3rem;
}

.faqpage {
    max-width: 1000px;
    margin: 20px auto;
    padding: 30px;
    background: white;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.faq-item {
    color: #2d3748;
    margin-bottom: 20px;
    font-size: 1.8rem;
}

.question {
    color: #2d3748;
    margin: 20px 0 10px 0;
    font-size: 1.2rem;
}

.answer {
    color: #4a5568;
    margin-bottom: 15px;
    line-height: 1.6;
}

@media (max-width: 768px) {
    .calc-header h2 {
        font-size: 1.6rem;
    }
    
    .tab-ibtn {
        min-width: 100px;
        padding: 10px 12px;
        font-size: 0.85rem;
    }
    
    .calc-panel {
        padding: 20px;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .grid-type-selector {
        grid-template-columns: 1fr;
    }
}