.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 40px 20px;
}

.header {
    text-align: center;
    margin-bottom: 40px;
    padding-bottom: 30px;
    border-bottom: 1px solid var(--border-color);
}

.header-icon {
    font-size: 3rem;
    margin-bottom: 15px;
}

.header h1 {
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 10px;
    letter-spacing: -0.025em;
}

.header p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 550px;
    margin: 0 auto;
}

.nav-back {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    margin-bottom: 20px;
    font-size: 1rem;
}

.nav-back:hover {
    color: var(--primary-hover);
}

.tax-info {
    background: var(--bg-light);
    padding: 30px;
    border-radius: 12px;
    margin-bottom: 30px;
}

.tax-info h2 {
    font-size: 1.35rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--text-primary);
    text-align: center;
}

.tax-rates {
    display: grid;
    gap: 15px;
}

.tax-rate-item {
    background: #ffffff;
    padding: 16px 20px;
    border-radius: 10px;
    border-left: 4px solid var(--primary-color);
    display: flex;
    align-items: flex-start;
    gap: 15px;
}

.tax-rate-percent {
    background: var(--primary-color);
    color: white;
    padding: 6px 14px;
    border-radius: 20px;
    font-weight: 700;
    font-size: 1.1rem;
    white-space: nowrap;
}

.tax-rate-desc {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
}

.calculator-card {
    background: var(--bg-article);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 35px;
    margin-bottom: 24px;
    transition: box-shadow 0.2s ease;
}

.calculator-card:hover {
    box-shadow: var(--shadow-md);
}

.card-header {
    display: flex;
    align-items: center;
    margin-bottom: 20px;
    gap: 12px;
}

.card-number {
    background: var(--primary-color);
    color: white;
    width: 36px;
    height: 36px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    font-weight: 700;
    flex-shrink: 0;
}

.card-title {
    font-size: 1.35rem;
    font-weight: 600;
    color: var(--text-primary);
}

.card-description {
    color: var(--text-secondary);
    margin-bottom: 20px;
    font-size: 1.05rem;
    line-height: 1.7;
    background: #ffffff;
    padding: 16px 18px;
    border-radius: 8px;
    border-left: 3px solid var(--primary-color);
}

.example {
    background: #ffffff;
    padding: 14px 18px;
    border-radius: 8px;
    margin-bottom: 20px;
    font-size: 1rem;
    color: var(--text-secondary);
    border-left: 3px solid var(--warning-color);
}

.example strong {
    color: var(--warning-color);
}

.input-group {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.input-group label {
    font-weight: 500;
    color: var(--text-primary);
}

.input-group select {
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1.05rem;
    background: #ffffff;
    color: var(--text-primary);
    cursor: pointer;
    min-width: 200px;
}

.input-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.input-group input {
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1.15rem;
    width: 160px;
    transition: all 0.2s;
    text-align: right;
    color: var(--text-primary);
    background: #ffffff;
}

.input-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.input-group input::placeholder {
    color: #9ca3af;
}

.input-group span {
    font-size: 1.05rem;
    color: var(--text-secondary);
}

.btn-calculate {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 12px 28px;
    border-radius: 8px;
    font-size: 1.05rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

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

.btn-calculate:active {
    transform: scale(0.98);
}

.result-box {
    background: #dcfce7;
    padding: 24px;
    border-radius: 10px;
    text-align: center;
    margin-top: 16px;
    display: none;
    border: 2px solid #86efac;
}

.result-box.show {
    display: block;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-5px); }
    to { opacity: 1; transform: translateY(0); }
}

.result-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px dashed #86efac;
}

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

.result-label {
    font-size: 1rem;
    color: var(--text-secondary);
}

.result-value {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--success-color);
}

.result-value.highlight {
    font-size: 1.5rem;
    color: var(--primary-color);
}

.result-divider {
    height: 2px;
    background: #86efac;
    margin: 12px 0;
}

.divider {
    border: none;
    height: 1px;
    background: var(--border-color);
    margin: 40px 0;
}

.note {
    background: #fef3c7;
    border: 1px solid #fcd34d;
    padding: 16px 20px;
    border-radius: 8px;
    margin-top: 15px;
    font-size: 0.95rem;
    color: #92400e;
}

.note strong {
    color: #b45309;
}

@media (max-width: 640px) {
    .container {
        padding: 20px 15px;
    }

    .header h1 {
        font-size: 1.6rem;
    }

    .calculator-card {
        padding: 20px;
    }

    .input-group {
        flex-direction: column;
        align-items: stretch;
    }

    .input-group input,
    .input-group select {
        width: 100%;
    }

    .btn-calculate {
        width: 100%;
        margin-top: 10px;
    }

    .tax-rate-item {
        flex-direction: column;
        gap: 10px;
    }

    .result-row {
        flex-direction: column;
        gap: 5px;
        text-align: left;
    }
}