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

body {
    font-family: 'Noto Sans KR', sans-serif;
    background: #f5f7fa;
    padding: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.calculator-container {
    width: 100%;
    max-width: 560px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    overflow: hidden;
}

/* 헤더 */
.header {
    background: white;
    padding: 20px;
    border-bottom: 1px solid #e8ecef;
    display: flex;
    align-items: center;
    gap: 12px;
}

.header .icon {
    font-size: 24px;
}

.header .title {
    font-size: 14px;
    color: #4a5568;
    line-height: 1.5;
}

/* 계산 폼 */
.calc-form {
    padding: 30px 20px;
}

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

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: #2d3748;
    margin-bottom: 8px;
}

.form-group select,
.form-group input {
    width: 100%;
    padding: 12px 16px;
    font-size: 15px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-family: 'Noto Sans KR', sans-serif;
    transition: all 0.2s;
    background: white;
}

.form-group select:focus,
.form-group input:focus {
    outline: none;
    border-color: #3182ce;
}

.form-group select {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg width='12' height='8' viewBox='0 0 12 8' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1.5L6 6.5L11 1.5' stroke='%234a5568' stroke-width='2' stroke-linecap='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 16px center;
    padding-right: 40px;
}

/* 폼 행 (2열 레이아웃) */
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.form-group.half {
    position: relative;
}

.form-group .unit {
    position: absolute;
    right: 16px;
    top: 40px;
    font-size: 14px;
    color: #718096;
    pointer-events: none;
}

/* 계산 버튼 */
.calc-button {
    width: 100%;
    padding: 16px;
    background: #3182ce;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    font-family: 'Noto Sans KR', sans-serif;
    margin-top: 10px;
}

.calc-button:hover {
    background: #2c5aa0;
}

.calc-button:active {
    transform: scale(0.98);
}

/* 결과 섹션 */
.result-section {
    background: #2d3748;
    padding: 24px 20px;
    animation: slideUp 0.3s ease-out;
}

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

.result-item {
    margin-bottom: 16px;
}

.result-item:last-child {
    margin-bottom: 0;
}

.result-label {
    font-size: 13px;
    color: #a0aec0;
    margin-bottom: 6px;
}

.result-value {
    font-size: 24px;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.result-value.notional {
    color: #63b3ed;
}

.result-value.margin {
    color: #68d391;
}

.result-value.ratio {
    color: #cbd5e0;
    font-size: 20px;
}

/* 반응형 */
@media (max-width: 600px) {
    body {
        padding: 10px;
    }

    .calculator-container {
        border-radius: 8px;
    }

    .header {
        padding: 16px;
    }

    .header .title {
        font-size: 13px;
    }

    .calc-form {
        padding: 24px 16px;
    }

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

    .result-value {
        font-size: 20px;
    }

    .result-value.ratio {
        font-size: 18px;
    }

    .result-section {
        padding: 20px 16px;
    }
}

/* 입력 필드 숫자 스피너 제거 (Chrome, Safari) */
input[type="number"]::-webkit-inner-spin-button,
input[type="number"]::-webkit-outer-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

/* 입력 필드 숫자 스피너 제거 (Firefox) */
input[type="number"] {
    -moz-appearance: textfield;
}