:root {
    --bg-primary: #f5f7fa;
    --bg-secondary: #ffffff;
    --bg-card: #ffffff;
    --text-primary: #0b1220;
    --text-muted: #64748b;
    --border-color: #e2e8f0;
    --accent: #06b6d4;
    --accent-hover: #0891b2;
    --secondary-bg: #f1f5f9;
    --secondary-hover: #e2e8f0;
}

* {
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    margin: 0;
    padding: 20px;
    line-height: 1.6;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
}

header {
    margin-bottom: 24px;
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 20px;
}

header > div {
    flex: 1;
}

.card {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 20px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
    margin-bottom: 16px;
}

.hidden {
    display: none !important;
}

/* Responsive (Minimal necessary adjustments) */
@media (max-width: 800px) {
    header {
        text-align: center;
        flex-direction: column;
        align-items: stretch;
    }

    .print-header-btn {
        width: 100%;
    }
}