.date-interval-section {
    min-height: 100vh;
    padding: 40px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.date-interval-section .container {
    max-width: 600px;
    margin: 0 auto;
    padding: 0 20px;
}

.calculator-header {
    text-align: center;
    margin-bottom: 30px;
}

.calculator-title {
    font-size: 28px;
    font-weight: 700;
    color: #fff;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.calculator-title i {
    font-size: 32px;
}

.calculator-subtitle {
    font-size: 16px;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 15px;
}

.calculator-badge {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
}

.badge-item {
    padding: 5px 15px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    font-size: 14px;
    color: #fff;
}

.calculator-main {
    background: #fff;
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

.input-section {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin-bottom: 25px;
}

.date-input-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.date-input-group label {
    font-weight: 600;
    color: #333;
    display: flex;
    align-items: center;
    gap: 8px;
}

.date-input-group label i {
    color: #667eea;
}

.form-control {
    width: 100%;
    padding: 14px 16px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 16px;
    transition: all 0.3s ease;
    box-sizing: border-box;
}

.form-control:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.time-input {
    margin-top: 8px;
}

.date-arrow {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 10px 0;
}

.date-arrow i {
    font-size: 24px;
    color: #667eea;
}

.calculate-btn-wrapper {
    display: flex;
    gap: 15px;
    margin-bottom: 30px;
}

.calculate-btn {
    flex: 1;
    padding: 15px 20px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.calculate-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.4);
}

.swap-btn {
    padding: 15px 20px;
    background: #f0f0f0;
    color: #666;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: all 0.2s ease;
}

.swap-btn:hover {
    background: #e0e0e0;
}

.result-section {
    background: #f8f9fa;
    border-radius: 15px;
    padding: 25px;
    margin-bottom: 25px;
}

.result-title {
    font-size: 18px;
    font-weight: 600;
    color: #333;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.result-title i {
    color: #667eea;
}

.result-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 15px;
    margin-bottom: 20px;
}

.result-card {
    background: #fff;
    border-radius: 12px;
    padding: 15px;
    text-align: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.result-value {
    display: block;
    font-size: 28px;
    font-weight: 700;
    color: #667eea;
    margin-bottom: 5px;
}

.result-label {
    font-size: 14px;
    color: #888;
}

.result-detail {
    border-top: 1px solid #e0e0e0;
    padding-top: 15px;
}

.detail-item {
    display: flex;
    justify-content: space-between;
    padding: 8px 0;
    border-bottom: 1px solid #f0f0f0;
}

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

.detail-label {
    color: #666;
    font-size: 14px;
}

.date-add-section {
    background: #f8f9fa;
    border-radius: 15px;
    padding: 25px;
    margin-bottom: 25px;
}

.section-title {
    font-size: 18px;
    font-weight: 600;
    color: #333;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.section-title i {
    color: #667eea;
}

.add-input-group {
    display: flex;
    gap: 10px;
    margin-bottom: 15px;
}

.add-input-group .form-control {
    flex: 1;
}

.num-input {
    max-width: 120px;
}

.btn {
    padding: 14px 20px;
    border: none;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.4);
}

.add-result {
    padding: 15px;
    background: #fff;
    border-radius: 10px;
    font-size: 16px;
}

.add-label {
    color: #666;
}

#add-result {
    color: #667eea;
    font-weight: 600;
    margin-left: 10px;
}

.tips-section {
    background: #fffbe6;
    border: 1px solid #ffe066;
    border-radius: 12px;
    padding: 20px;
}

.tips-list {
    margin: 0;
    padding-left: 20px;
}

.tips-list li {
    padding: 8px 0;
    color: #8b7355;
    font-size: 14px;
}

@media (max-width: 480px) {
    .calculator-main {
        padding: 20px;
    }

    .result-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .calculate-btn-wrapper {
        flex-direction: column;
    }

    .add-input-group {
        flex-direction: column;
    }

    .num-input {
        max-width: 100%;
    }
}