:root {
    --primary-color: #4a90e2;
    --primary-hover: #357abd;
    --secondary-color: #f5f5f7;
    --text-color: #333;
    --text-light: #666;
    --border-color: #ddd;
    --error-color: #e74c3c;
    --success-color: #2ecc71;
    --background-color: #fff;
    --card-bg: #f9f9f9;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --radius: 8px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #f0f2f5;
    display: flex;
    justify-content: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 800px;
    background-color: var(--background-color);
    padding: 40px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

header {
    text-align: center;
    margin-bottom: 40px;
}

header h1 {
    font-size: 2rem;
    margin-bottom: 10px;
    color: #2c3e50;
}

header p {
    color: var(--text-light);
}

section {
    margin-bottom: 30px;
}

h2 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: #2c3e50;
    border-bottom: 2px solid var(--secondary-color);
    padding-bottom: 10px;
}

.description {
    font-size: 0.95rem;
    color: var(--text-light);
    margin-bottom: 15px;
}

.textarea-wrapper {
    margin-bottom: 15px;
}

textarea {
    width: 100%;
    height: 120px;
    padding: 15px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-family: inherit;
    font-size: 1rem;
    resize: vertical;
    transition: border-color 0.3s;
}

textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(74, 144, 226, 0.1);
}

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

button {
    padding: 10px 20px;
    border: none;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
}

button:active {
    transform: translateY(1px);
}

.primary-btn {
    background-color: var(--primary-color);
    color: white;
    flex: 1;
}

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

.secondary-btn {
    background-color: var(--secondary-color);
    color: var(--text-color);
    border: 1px solid var(--border-color);
}

.secondary-btn:hover {
    background-color: #e4e6e9;
}

.text-btn {
    background: none;
    color: var(--primary-color);
    font-weight: normal;
    text-decoration: underline;
    padding: 10px;
}

.text-btn:hover {
    color: var(--primary-hover);
}

.error-message {
    color: var(--error-color);
    background-color: #fdecea;
    padding: 10px;
    border-radius: var(--radius);
    font-size: 0.9rem;
    margin-top: 10px;
}

.summary-cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-bottom: 30px;
}

.card {
    background-color: var(--card-bg);
    padding: 20px;
    border-radius: var(--radius);
    text-align: center;
    border: 1px solid var(--secondary-color);
}

.card.highlight {
    background-color: #e8f4fc;
    border-color: #bbdefb;
}

.card-label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-light);
    margin-bottom: 5px;
}

.card-value {
    display: block;
    font-size: 1.5rem;
    font-weight: 700;
    color: #2c3e50;
}

.card-sub {
    display: block;
    font-size: 0.75rem;
    color: var(--text-light);
    margin-top: 5px;
}

.chart-container {
    background-color: white;
    padding: 20px 0;
    margin-bottom: 30px;
    height: 150px; /* 차트 높이 줄임 */
}

.range-details {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.range-item {
    padding: 15px;
    border-radius: var(--radius);
    border-left: 4px solid #ddd;
}

.range-item.min {
    background-color: #f0f9eb;
    border-left-color: var(--success-color);
}

.range-item.max {
    background-color: #fef6f6;
    border-left-color: var(--error-color);
}

.range-item .label {
    display: block;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 5px;
}

.range-item .value {
    display: block;
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 5px;
}

.range-item .desc {
    font-size: 0.8rem;
    color: var(--text-light);
}

.info-section {
    background-color: #fcfcfc;
    border-top: 1px solid var(--border-color);
    padding-top: 30px;
}

.info-section h3 {
    font-size: 1.1rem;
    margin-bottom: 10px;
}

.info-section p {
    font-size: 0.9rem;
    color: var(--text-light);
    margin-bottom: 15px;
}

.info-section ul {
    padding-left: 20px;
    font-size: 0.9rem;
    color: var(--text-light);
}

footer {
    text-align: center;
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid var(--secondary-color);
    font-size: 0.8rem;
    color: #999;
}

.hidden {
    display: none;
}

/* Responsive */
@media (max-width: 600px) {
    .container {
        padding: 20px;
    }
    
    .summary-cards {
        grid-template-columns: 1fr;
    }
    
    .range-details {
        grid-template-columns: 1fr;
    }
}