:root {
    --primary: #fbbf24;
    --primary-dark: #f59e0b;
    --bg-dark: #0f172a;
    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    --text-main: #f8fafc;
    --text-dim: #94a3b8;
    --warning: #f87171;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: 'Pretendard', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    padding: 40px 20px;
}

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

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

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-bottom: 10px;
}

.logo-icon {
    font-size: 3.5rem;
}

h1 {
    font-size: 3rem;
    font-weight: 900;
    letter-spacing: -1px;
}

.subtitle {
    font-size: 1.25rem;
    font-weight: 500;
    color: var(--text-dim);
}

.glass {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 30px;
}

.calc-card {
    display: flex;
    flex-direction: column;
    gap: 25px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    margin-bottom: 40px;
}

.input-group label {
    display: block;
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--primary);
}

/* Radio buttons */
.radio-group {
    display: flex;
    gap: 15px;
}

.radio-label {
    flex: 1;
    cursor: pointer;
}

.radio-label input {
    display: none;
}

.radio-custom {
    display: block;
    background: rgba(255, 255, 255, 0.05);
    border: 2px solid var(--glass-border);
    padding: 20px;
    border-radius: 12px;
    text-align: center;
    font-weight: 700;
    transition: all 0.2s;
}

.radio-label input:checked+.radio-custom {
    background: var(--primary);
    color: black;
    border-color: var(--primary);
    transform: scale(1.02);
}

/* Number inputs */
.price-input,
.weight-input {
    display: flex;
    align-items: center;
    background: rgba(0, 0, 0, 0.3);
    border: 2px solid var(--glass-border);
    border-radius: 12px;
    overflow: hidden;
}

.price-input:focus-within,
.weight-input:focus-within {
    border-color: var(--primary);
}

.unit {
    padding: 0 15px;
    font-size: 1.3rem;
    font-weight: 800;
    color: var(--text-dim);
}

input[type="number"],
select {
    width: 100%;
    background: transparent;
    border: none;
    color: white;
    padding: 18px 20px;
    font-size: 1.5rem;
    font-weight: 700;
    outline: none;
}

select {
    background: rgba(0, 0, 0, 0.3);
    border: 2px solid var(--glass-border);
    border-radius: 12px;
    cursor: pointer;
}

.primary-btn {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: black;
    border: none;
    padding: 20px;
    border-radius: 12px;
    font-size: 1.4rem;
    font-weight: 900;
    cursor: pointer;
    transition: transform 0.2s;
    margin-top: 10px;
}

.primary-btn:hover {
    transform: translateY(-2px);
    opacity: 0.9;
}

/* Result Area */
.result-area.hidden {
    display: none;
}

.result-card {
    text-align: center;
    margin-bottom: 30px;
    border-left: 8px solid var(--primary);
}

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

.result-main h2 {
    font-size: 3.5rem;
    font-weight: 900;
    color: var(--primary);
    margin: 10px 0;
}

.result-details {
    margin-top: 25px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.detail-item {
    display: flex;
    justify-content: space-between;
    font-size: 1.2rem;
    font-weight: 600;
    padding: 10px 0;
    border-bottom: 1px dashed var(--glass-border);
}

.alert {
    color: var(--warning);
}

.warning-box {
    background: rgba(248, 113, 113, 0.1);
    border: 1px solid var(--warning);
    border-radius: 12px;
    padding: 15px;
    margin-top: 25px;
    color: var(--warning);
    font-weight: 700;
}

.ad-slot {
    text-align: center;
    min-height: 100px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    margin-bottom: 30px;
    border: 2px dashed var(--glass-border);
}

.affiliate-box h3 {
    margin-bottom: 20px;
    font-size: 1.3rem;
}

.aff-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}

.aff-card {
    background: rgba(255, 255, 255, 0.05);
    padding: 20px;
    border-radius: 12px;
    text-align: center;
    text-decoration: none;
    color: white;
    font-weight: 700;
    border: 1px solid transparent;
    transition: all 0.2s;
}

.aff-card:hover {
    border-color: var(--primary);
    transform: translateY(-3px);
}

footer {
    text-align: center;
    margin-top: 50px;
    padding-bottom: 40px;
    color: var(--text-dim);
    font-size: 1rem;
}

@media (max-width: 600px) {
    body {
        padding: 20px 10px;
    }

    h1 {
        font-size: 2.22rem;
    }

    .logo-icon {
        font-size: 2.5rem;
    }

    .glass {
        padding: 20px;
    }

    .radio-custom {
        padding: 15px 5px;
        font-size: 0.9rem;
    }

    input[type="number"],
    select {
        font-size: 1.2rem;
        padding: 15px;
    }

    .result-main h2 {
        font-size: 2.5rem;
    }

    .detail-item {
        font-size: 1rem;
    }

    .primary-btn {
        font-size: 1.2rem;
    }
}