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

body {
    font-family: monospace;
    background: #f5f6fa;
    color: #333;
    line-height: 1.5;
}

.main-content {
    max-width: 1000px;
    margin: 0 auto;
    padding: 30px;
    background: white;
    min-height: 100vh;
}

.invoice-header {
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px solid #e1e8ed;
}

.invoice-header h1 {
    font-size: 24px;
    color: #2c3e50;
    font-weight: 600;
}

.status-badge {
    background: #f39c12;
    color: white;
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.invoice-form {
    width: 100%;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 20px;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    font-size: 11px;
    font-weight: 500;
    color: #6b7280;
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: .1em;
}

.form-group input,
.form-group select,
.form-group textarea {
    padding: 11px 14px;
    border: 1px solid #d1d5db;
    border-radius: 6px;
    font-size: 13px;
    font-weight: 400;
    background: white;
    color: #374151;
    font-family: inherit;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 3px rgba(52,152,219,.1);
}

.items-section {
    margin: 30px 0;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 8px;
}

.items-section h3 {
    margin-bottom: 20px;
    color: #2c3e50;
    font-size: 18px;
}

.items-header {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr 50px;
    gap: 15px;
    padding: 10px 0;
    border-bottom: 1px solid #ddd;
    font-size: 11px;
    font-weight: 500;
    color: #6b7280;
    text-transform: uppercase;
    letter-spacing: .1em;
}

.item-row {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr 50px;
    gap: 15px;
    align-items: center;
    padding: 15px 0;
    border-bottom: 1px solid #eee;
}

.item-row input {
    padding: 10px 12px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 13px;
    font-family: inherit;
}

.item-total {
    font-weight: 600;
    color: #2c3e50;
}

.btn-remove-item {
    width: 40px;
    height: 40px;
    border: none;
    background: #dc3545;
    color: white;
    border-radius: 6px;
    cursor: pointer;
    font-size: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    font-weight: 500;
    font-family: monospace;
}

.btn-remove-item:hover {
    background: #c82333;
    transform: translateY(-1px);
    box-shadow: 0 2px 4px rgba(220,53,69,0.3);
}

.btn-add-item {
    margin-top: 15px;
    padding: 14px 28px;
    background: #28a745;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 16px;
    font-weight: 600;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-family: monospace;
}

.btn-add-item:hover {
    background: #218838;
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(40,167,69,0.25);
}

.tax-discount-row {
    display: grid;
    grid-template-columns: 1fr 80px 20px 100px;
    gap: 10px;
    align-items: center;
    margin-bottom: 10px;
    min-height: 42px;
}

.tax-label,
.discount-label {
    padding: 11px 14px;
    border: 1px solid #d1d5db;
    border-radius: 6px;
    font-size: 14px;
}

.tax-percent,
.discount-percent {
    padding: 11px 14px;
    border: 1px solid #d1d5db;
    border-radius: 6px;
    text-align: center;
    font-size: 14px;
    font-family: inherit;
}

.percent-symbol {
    color: #7f8c8d;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    min-height: 42px;
}

.tax-amount,
.discount-amount {
    font-weight: 600;
    text-align: right;
    color: #2c3e50;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    font-size: 14px;
    min-height: 42px;
}

.message-section {
    margin-top: 25px;
}

.form-actions {
    display: flex;
    gap: 15px;
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid #e1e8ed;
    justify-content: flex-end;
}

.btn-reset {
    padding: 12px 24px;
    background: #3498db;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    font-family: monospace;
}

.btn-cancel {
    padding: 12px 24px;
    background: transparent;
    color: #7f8c8d;
    border: 1px solid #ddd;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    font-family: monospace;
}

.btn-generate {
    padding: 12px 24px;
    background: #c05b3c;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    font-family: monospace;
}

.invoice-summary {
    width: 100%;
    margin: 30px 0 0 0;
    background: white;
    border: 1px solid #e1e8ed;
    border-radius: 8px;
    padding: 20px;
}

.summary-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px solid #f1f3f4;
    font-size: 14px;
}

.total-row {
    font-size: 18px;
    font-weight: 600;
    color: #2c3e50;
    border-top: 2px solid #e1e8ed;
    padding-top: 15px;
    margin-top: 10px;
}

.success-message {
    position: fixed;
    top: 20px;
    right: 20px;
    background: #27ae60;
    color: white;
    padding: 15px 20px;
    border-radius: 6px;
    z-index: 1000;
    transform: translateX(100%);
}

.success-message.show {
    transform: translateX(0);
}

@media (max-width: 768px) {
    input[type="text"],
    input[type="number"],
    input[type="date"],
    select,
    textarea {
        font-size: 16px !important;
    }

    .main-content {
        padding: 20px;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .items-header,
    .item-row {
        grid-template-columns: 1fr;
        gap: 10px;
    }

    .tax-discount-row {
        grid-template-columns: 1fr 70px 25px 90px;
        gap: 8px;
        align-items: center;
        min-height: 48px;
    }

    .form-actions {
        flex-direction: column;
    }

    .btn-reset,
    .btn-cancel,
    .btn-generate {
        width: 100%;
    }
}