:root {
    --container-width: 1200px;
    --container-padding: 20px;
    --header-height: 64px;
    --footer-height: auto;
    --sidebar-width: 280px;

    --font-ui: 'Roboto', system-ui, -apple-system, sans-serif;
    --font-code: 'JetBrains Mono', monospace;

    --transition-duration: 0.2s;
    --md-easing: cubic-bezier(0.2, 0, 0, 1);
    --transition-theme: background-color 0.3s var(--md-easing), color 0.3s var(--md-easing), border-color 0.3s var(--md-easing);

    --shape-small: 8px;
    --shape-medium: 12px;
    --shape-large: 16px;
    --shape-pill: 100px;

    --bg-color: #121316;
    --surface-color: #1E1F22;
    --surface-variant: #2B2D31;

    --primary-color: #3ddc84;
    --on-primary: #00391B;

    --text-primary: #E2E2E5;
    --text-secondary: #A0A0A5;

    --color-h2: #6CB6FF;
    --color-h3: #7986CB;
    --color-h4: #4DB6AC;

    --border-color: rgba(255, 255, 255, 0.08);
    --hover-overlay: rgba(255, 255, 255, 0.05);
    --active-overlay: rgba(61, 220, 132, 0.12);

    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -2px rgba(0, 0, 0, 0.3);

    --brand-gradient: linear-gradient(90deg, var(--color-h2), var(--color-h3), var(--color-h4), var(--primary-color));
}

[data-theme="light"] {
    --bg-color: #F8FDF9;
    --surface-color: #FFFFFF;
    --surface-variant: #E8F0EA;

    --primary-color: #1E8E3E;
    --on-primary: #FFFFFF;

    --text-primary: #1A1C19;
    --text-secondary: #424940;

    --color-h2: #005CC5;
    --color-h3: #3949AB;
    --color-h4: #00796B;

    --border-color: rgba(0, 0, 0, 0.08);
    --hover-overlay: rgba(0, 0, 0, 0.04);
    --active-overlay: rgba(30, 142, 62, 0.12);

    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -2px rgba(0, 0, 0, 0.03);

    --brand-gradient: linear-gradient(90deg, var(--color-h2), var(--color-h3), var(--color-h4), var(--primary-color));
}

body {
    margin: 0;
    padding: 0;
    font-family: var(--font-ui);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    background: var(--bg-color);
    color: var(--text-primary);
    transition: var(--transition-theme);
    -webkit-font-smoothing: antialiased;
}

.main-container {
    display: flex;
    min-height: calc(100vh - var(--header-height));
    flex: 1;
    width: clamp(1200px, 60%, 1800px);
    margin: 0 auto;
    box-sizing: border-box;
    position: relative;
}

::selection {
    background: var(--color-h3);
    color: #ffffff;
}

::-moz-selection {
    background: var(--color-h3);
    color: #ffffff;
}