:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border-color: #334155;
    --accent-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

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

body {
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.app-container {
    width: 100%;
    max-width: 1200px;
    background-color: rgba(30, 41, 59, 0.5);
    backdrop-filter: blur(20px);
    border-radius: 24px;
    padding: 40px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: var(--shadow-lg);
}

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

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    margin-bottom: 8px;
    color: var(--primary-color);
}

h1 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-main);
}

.subtitle {
    color: var(--text-muted);
    font-size: 1rem;
}

.calculator-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 40px;
}

section {
    background-color: var(--card-bg);
    padding: 30px;
    border-radius: 20px;
    border: 1px solid var(--border-color);
}

h2 {
    font-size: 1.25rem;
    margin-bottom: 24px;
    color: var(--text-main);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 12px;
}

h3 {
    font-size: 0.95rem;
    color: var(--text-muted);
    margin-bottom: 16px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-weight: 600;
}

.input-group {
    margin-bottom: 32px;
}

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

.input-field {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

label {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-muted);
    text-align: center;
    white-space: nowrap;
}

input {
    background-color: #0f172a;
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 10px;
    color: var(--text-main);
    font-size: 0.95rem;
    transition: all 0.2s ease;
    width: 100%;
    text-align: center;
}

input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
}

input::placeholder {
    color: #475569;
}

.help-text {
    font-size: 0.8rem;
    color: #64748b;
}

.grid-inputs {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 8px;
    align-items: end;
}

.badge {
    font-size: 0.75rem;
    background-color: #334155;
    padding: 2px 6px;
    border-radius: 4px;
    margin-left: 6px;
    color: #94a3b8;
}

/* Result Panel Styles */
.result-panel {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.result-card {
    background-color: #0f172a;
    border-radius: 16px;
    padding: 24px;
    border: 1px solid var(--border-color);
}

.result-card.primary {
    background: linear-gradient(to bottom right, #1e293b, #0f172a);
    border: 1px solid var(--primary-color);
}

.result-header {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
}

.result-value-group {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.result-value-group.vertical {
    grid-template-columns: 1fr;
    gap: 16px;
}

.result-value-group.vertical .result-item {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 12px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.result-value-group.vertical .result-item:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.result-value-group.vertical .result-item .value {
    font-size: 1.25rem;
}

.result-item {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.result-item .label {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.result-item .value {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-color);
}





footer {
    text-align: center;
    margin-top: 40px;
    color: #475569;
    font-size: 0.9rem;
}

.save-btn {
    width: 100%;
    padding: 16px;
    border-radius: 12px;
    border: none;
    background: var(--card-bg);
    color: var(--text-main);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    border: 1px solid var(--border-color);
    margin-top: 20px;
}

.save-btn:hover {
    background: var(--primary-color);
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.save-btn .icon {
    font-size: 1.2rem;
}

/* Responsive adjustments */
@media (max-width: 900px) {
    .calculator-grid {
        grid-template-columns: 1fr;
    }
}