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

:root {
    --primary-color: #0066cc;
    --primary-hover: #0052a3;
    --secondary-color: #6c757d;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --light-bg: #f8f9fa;
    --border-color: #dee2e6;
    --text-color: #212529;
    --text-muted: #6c757d;
    --shadow: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-lg: 0 4px 12px rgba(0,0,0,0.15);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    overflow: hidden;
}

/* 헤더 */
header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 40px 30px;
    text-align: center;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    font-weight: 700;
}

.subtitle {
    font-size: 1.1rem;
    opacity: 0.95;
}

/* 탭 */
.tabs {
    display: flex;
    background: var(--light-bg);
    border-bottom: 2px solid var(--border-color);
}

.tab-button {
    flex: 1;
    padding: 18px 20px;
    border: none;
    background: transparent;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-muted);
    transition: all 0.3s ease;
    position: relative;
}

.tab-button:hover {
    background: rgba(102, 126, 234, 0.1);
    color: var(--primary-color);
}

.tab-button.active {
    color: var(--primary-color);
    background: white;
}

.tab-button.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--primary-color);
}

/* 탭 콘텐츠 */
.tab-content {
    display: none;
    padding: 30px;
    animation: fadeIn 0.3s ease;
}

.tab-content.active {
    display: block;
}

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

/* 폼 */
.calculator-form h2 {
    color: var(--primary-color);
    margin-bottom: 25px;
    font-size: 1.8rem;
    border-bottom: 2px solid var(--light-bg);
    padding-bottom: 10px;
}

.form-section {
    margin-bottom: 30px;
    padding: 20px;
    background: var(--light-bg);
    border-radius: 12px;
}

.form-section h3 {
    color: var(--text-color);
    font-size: 1.3rem;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.form-section h3::before {
    content: '●';
    color: var(--primary-color);
    margin-right: 10px;
    font-size: 0.8rem;
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--text-color);
}

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

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

.form-group small {
    display: block;
    margin-top: 5px;
    color: var(--text-muted);
    font-size: 0.85rem;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

.checkbox-group label {
    display: flex;
    align-items: center;
    cursor: pointer;
    font-weight: normal;
}

.checkbox-group input[type="checkbox"] {
    width: auto;
    margin-right: 8px;
    cursor: pointer;
    transform: scale(1.2);
}

.daily-wage-group {
    margin-bottom: 20px;
    padding: 15px;
    background: white;
    border-radius: 8px;
}

.daily-wage-group label {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 10px;
    display: block;
}

/* 버튼 */
.button-group {
    display: flex;
    gap: 15px;
    margin-top: 30px;
}

.btn {
    flex: 1;
    padding: 15px 30px;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: none;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: var(--secondary-color);
    color: white;
}

.btn-secondary:hover {
    background: #5a6268;
    transform: translateY(-2px);
}

/* 결과 영역 */
.result-area {
    margin: 30px;
    padding: 30px;
    background: linear-gradient(135deg, #667eea15 0%, #764ba215 100%);
    border-radius: 12px;
    border: 2px solid var(--primary-color);
    animation: slideIn 0.5s ease;
}

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

.result-area h2 {
    color: var(--primary-color);
    margin-bottom: 20px;
    font-size: 1.8rem;
}

.result-content {
    background: white;
    padding: 25px;
    border-radius: 8px;
    margin-bottom: 20px;
}

.result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
    border-bottom: 1px solid var(--border-color);
}

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

.result-label {
    font-weight: 600;
    color: var(--text-color);
    font-size: 1.1rem;
}

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

.result-value.total {
    font-size: 1.8rem;
    color: var(--success-color);
}

.result-error {
    padding: 20px;
    background: #f8d7da;
    border: 1px solid #f5c6cb;
    border-radius: 8px;
    color: #721c24;
}

.result-disclaimer {
    padding: 20px;
    background: #fff3cd;
    border: 1px solid #ffc107;
    border-radius: 8px;
    font-size: 0.9rem;
    color: #856404;
}

.result-disclaimer p {
    margin-bottom: 8px;
}

.result-disclaimer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
}

.result-disclaimer a:hover {
    text-decoration: underline;
}

/* 푸터 */
footer {
    padding: 20px 30px;
    background: var(--light-bg);
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

footer a {
    color: var(--primary-color);
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

/* 반응형 디자인 */
@media (max-width: 768px) {
    body {
        padding: 10px;
    }

    header h1 {
        font-size: 1.8rem;
    }

    .subtitle {
        font-size: 0.95rem;
    }

    .container {
        border-radius: 12px;
    }

    .tab-content {
        padding: 20px;
    }

    .form-row {
        grid-template-columns: 1fr;
        gap: 0;
    }

    .button-group {
        flex-direction: column;
    }

    .tab-button {
        font-size: 0.9rem;
        padding: 15px 10px;
    }

    .result-area {
        margin: 20px;
        padding: 20px;
    }

    .result-value {
        font-size: 1.1rem;
    }

    .result-value.total {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    header {
        padding: 30px 20px;
    }

    header h1 {
        font-size: 1.5rem;
    }

    .tab-button {
        font-size: 0.85rem;
        padding: 12px 8px;
    }
}