:root {
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --text-color: #f1f5f9;
    --accent-color: #38bdf8;
    --profit-color: #4ade80;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
    margin: 0;
    padding: 20px;
    display: flex;
    justify-content: center;
}

.container {
    max-width: 800px;
    width: 100%;
}

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

h1 {
    font-size: 2rem;
    margin: 0;
    background: linear-gradient(to right, #38bdf8, #818cf8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.ad-banner {
    background-color: #334155;
    height: 80px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #94a3b8;
    margin-bottom: 20px;
    border: 1px dashed #475569;
}

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

@media (min-width: 768px) {
    .calculator-grid {
        grid-template-columns: 1fr 1fr;
    }
}

.controls-card, .result-card {
    background-color: var(--card-bg);
    padding: 20px;
    border-radius: 15px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

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

.input-group label {
    display: flex;
    justify-content: space-between;
    margin-bottom: 8px;
    font-weight: 500;
}

.highlight {
    color: var(--accent-color);
    font-weight: bold;
}

input[type="range"] {
    width: 100%;
    height: 6px;
    background: #334155;
    border-radius: 5px;
    outline: none;
    -webkit-appearance: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 20px;
    height: 20px;
    background: var(--accent-color);
    border-radius: 50%;
    cursor: pointer;
    transition: transform 0.1s;
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

.total-amount {
    font-size: 2.5rem;
    font-weight: bold;
    color: var(--text-color);
    margin: 10px 0 20px 0;
    word-break: keep-all;
}

.breakdown .item {
    display: flex;
    justify-content: space-between;
    margin-bottom: 8px;
    font-size: 0.9rem;
    color: #94a3b8;
}

.breakdown .profit {
    color: var(--profit-color);
    font-weight: bold;
}

.chart-container {
    background-color: var(--card-bg);
    padding: 20px;
    border-radius: 15px;
    height: 300px;
    position: relative;
}