:root {
    --bg-color: #0f172a;
    --panel-bg: rgba(30, 41, 59, 0.7);
    --panel-border: rgba(255, 255, 255, 0.1);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-color: #8b5cf6;
    --accent-hover: #7c3aed;
    --success-color: #10b981;
    --glass-blur: blur(16px);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    background-image: 
        radial-gradient(circle at 15% 50%, rgba(139, 92, 246, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 85% 30%, rgba(16, 185, 129, 0.1) 0%, transparent 50%);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    padding: 2rem;
}

.app-container {
    max-width: 1200px;
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.app-header {
    text-align: center;
    margin-bottom: 1rem;
}

.app-header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -0.025em;
    margin-bottom: 0.5rem;
}

.app-header h1 span {
    color: var(--accent-color);
}

.app-header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.main-content {
    display: grid;
    grid-template-columns: 1fr 350px;
    gap: 2rem;
    align-items: start;
}

.calculator-panel {
    background: var(--panel-bg);
    border: 1px solid var(--panel-border);
    border-radius: 24px;
    padding: 2rem;
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
}

.section-header {
    margin-bottom: 2rem;
    display: flex;
    align-items: baseline;
    gap: 1rem;
}

.section-header h2 {
    font-size: 1.5rem;
    font-weight: 600;
}

.section-header .subtitle {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.options-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.option-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 16px;
    padding: 1.25rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    transition: var(--transition);
    cursor: pointer;
}

.option-card:hover {
    background: rgba(255, 255, 255, 0.06);
    border-color: rgba(255, 255, 255, 0.1);
    transform: translateY(-2px);
}

.option-card.active {
    background: rgba(139, 92, 246, 0.1);
    border-color: var(--accent-color);
}

.option-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.option-title-group {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.custom-checkbox {
    width: 24px;
    height: 24px;
    border-radius: 6px;
    border: 2px solid var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.option-card.active .custom-checkbox {
    background: var(--accent-color);
    border-color: var(--accent-color);
}

.custom-checkbox svg {
    width: 14px;
    height: 14px;
    fill: none;
    stroke: white;
    stroke-width: 3;
    stroke-linecap: round;
    stroke-linejoin: round;
    opacity: 0;
    transform: scale(0.5);
    transition: var(--transition);
}

.option-card.active .custom-checkbox svg {
    opacity: 1;
    transform: scale(1);
}

.option-title {
    font-size: 1rem;
    font-weight: 600;
}

.option-impacts {
    display: flex;
    gap: 1rem;
    font-size: 0.875rem;
}

.impact-time {
    color: var(--accent-color);
    font-weight: 600;
}

.impact-cost {
    color: var(--success-color);
    font-weight: 600;
}

.impact-none {
    color: var(--text-secondary);
}

/* Dynamic Inputs inside options */
.option-inputs {
    display: none;
    padding-top: 1rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    animation: fadeIn 0.3s ease;
}

.option-card.active .option-inputs.has-inputs {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.input-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.input-group label {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.input-group input[type="number"] {
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: white;
    border-radius: 8px;
    padding: 0.5rem;
    width: 70px;
    font-family: 'Inter', sans-serif;
    outline: none;
    transition: var(--transition);
}

.input-group input[type="number"]:focus {
    border-color: var(--accent-color);
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-5px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Summary Panel */
.summary-panel-container {
    position: sticky;
    top: 2rem;
}

.summary-panel {
    background: var(--panel-bg);
    border: 1px solid var(--panel-border);
    border-radius: 24px;
    padding: 2rem;
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.summary-panel h2 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.summary-metric {
    background: rgba(0, 0, 0, 0.2);
    border-radius: 16px;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.summary-metric.highlight {
    background: linear-gradient(145deg, rgba(139, 92, 246, 0.15), rgba(139, 92, 246, 0.05));
    border: 1px solid rgba(139, 92, 246, 0.2);
}

.metric-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-weight: 600;
}

.metric-value {
    font-size: 3rem;
    font-weight: 700;
    line-height: 1;
    display: flex;
    align-items: baseline;
    gap: 0.25rem;
}

.metric-value .unit {
    font-size: 1rem;
    color: var(--text-secondary);
    font-weight: 400;
}

.metric-value .currency {
    font-size: 2rem;
    color: var(--success-color);
}

.summary-metric.highlight .metric-value {
    color: white;
}

.metric-breakdown {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.active-addons {
    margin-top: 1rem;
}

.active-addons h3 {
    font-size: 0.875rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 1rem;
}

.active-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.active-list li {
    font-size: 0.875rem;
    display: flex;
    justify-content: space-between;
    padding: 0.5rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.active-list li:last-child {
    border-bottom: none;
}

.active-list .empty-state {
    color: var(--text-secondary);
    font-style: italic;
    justify-content: center;
    border: none;
}

.addon-name {
    color: var(--text-primary);
}

.addon-details {
    color: var(--accent-color);
    font-weight: 600;
}

@media (max-width: 900px) {
    .main-content {
        grid-template-columns: 1fr;
    }
    
    .summary-panel-container {
        position: static;
        order: -1;
    }
}