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

* {
    cursor: default;
}

:root {
    --bg: #0b0f19;
    --text: #a9dce3;
    --text-dim: #8fa9a3;
    --tile-bg: #111722;
    --tile-border: #202936;
    --tile-accent: #38bdf8;
    --font-display: "Space Grotesk", -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: "JetBrains Mono", ui-monospace, monospace;
    --gap: 16px;
    --max-width: 1040px;
    --shadow-sm: 0 8px 20px rgba(0, 0, 0, 0.4), 0 10px 18px rgba(56, 189, 248, 0.07);
    --shadow-hover: 0 20px 40px -10px rgba(0, 0, 0, 0.6), 0 14px 24px rgba(56, 189, 248, 0.12);
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
}

html {
    color-scheme: dark;
    text-rendering: optimizeLegibility;
    scrollbar-gutter: stable;
    scroll-behavior: smooth;
    scrollbar-color: var(--tile-accent) var(--tile-border);
}

body {
    min-height: 100vh;
    background: var(--bg);
    color: var(--text);
    font-family: var(--font-display);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transition: background 0.3s var(--ease-out), color 0.3s var(--ease-out);
}

a {
    color: inherit;
    text-decoration: none;
    cursor: pointer;
}

button {
    font-family: inherit;
}

/* container */
.container {
    width: 100%;
    max-width: var(--max-width);
    min-height: 100vh;
    min-height: 100dvh;
    margin: 0 auto;
    padding: 32px 24px 48px;
    display: flex;
    flex-direction: column;
}

/* section index */
.section-index {
    display: flex;
    align-items: center;
    gap: 14px;
    color: var(--text-dim);
    font-family: var(--font-mono);
    font-weight: 500;
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.section-index span:first-child {
    color: var(--tile-accent);
}

/* buttons */
.btn-primary,
.btn-secondary {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    border: 1px solid var(--tile-border);
    border-radius: 999px;
    font-family: var(--font-mono);
    font-weight: 500;
    cursor: pointer;
    transition:
        transform 0.25s var(--ease-out),
        color 0.25s ease,
        border-color 0.25s ease,
        background-color 0.25s ease;
}

.btn-primary *,
.btn-secondary * {
    cursor: pointer;
}

.btn-primary {
    background: var(--tile-accent);
    border-color: var(--tile-accent);
    color: var(--bg);
}

.btn-secondary {
    background: transparent;
    color: var(--text);
}

.btn-primary:hover,
.btn-secondary:hover {
    transform: translateY(-3px);
}

.btn-primary:hover {
    background: transparent;
    color: var(--tile-accent);
}

.btn-secondary:hover {
    border-color: var(--tile-accent);
    color: var(--tile-accent);
}

/* pills */
.pill {
    display: inline-flex;
    align-items: center;
    padding: 5px 10px;
    border: 1px solid var(--tile-border);
    border-radius: 999px;
    background: color-mix(in srgb, var(--text) 4%, transparent);
    color: var(--text-dim);
    font-family: var(--font-mono);
    font-size: 0.75rem;
    line-height: 1;
    transition:
        border-color 0.25s ease,
        color 0.25s ease,
        background-color 0.25s ease;
}

.pill:hover {
    border-color: var(--tile-accent);
    color: var(--tile-accent);
    background: color-mix(in srgb, var(--tile-accent) 8%, transparent);
}

@media (max-width: 800px) {
    .site-header {
        position: relative;
        z-index: 60;
    }

    .brand i,
    .brand-title {
        font-size: 1.2rem;
    }

    .menu-toggle {
        display: inline-flex;
    }

    .site-nav {
        position: fixed;
        top: 20px;
        left: 16px;
        right: 16px;
        display: flex;
        flex-direction: column;
        align-items: flex-start;
        gap: 0;
        padding: 12px 20px;
        background: rgba(17, 23, 34, 0.72);
        border: 1px solid rgba(56, 189, 248, 0.12);
        border-radius: 18px;
        backdrop-filter: blur(18px);
        -webkit-backdrop-filter: blur(18px);
        box-shadow: var(--shadow-sm);
        transform: translateY(-20px);
        opacity: 0;
        visibility: hidden;
        pointer-events: none;
        z-index: 50;
        transition: transform 0.35s var(--ease-out), opacity 0.25s ease, visibility 0.35s ease;
    }

    .site-nav.open {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
        pointer-events: auto;
    }

    .site-nav a {
        display: flex;
        align-items: center;
        justify-content: flex-start;
        width: 100%;
        min-height: 50px;
        padding: 8px 0;
        border-bottom: 1px solid rgba(32, 41, 54, 0.7);
        color: var(--text-dim);
        font-size: 1.15rem;
        text-align: left;
        transition: color 0.2s ease;
    }

    .site-nav a:last-child {
        border-bottom: none;
    }

    .site-nav a:hover {
        color: var(--tile-accent);
    }
}