/* Explain: Base styles, resets, and typography defaults. */
* {
    box-sizing: border-box;
}

html {
    background: var(--background-color);
    scroll-behavior: smooth;
}

body {
    overflow-x: hidden;
    font-family: var(--font-body);
    color: var(--text-color);
    background: var(--background-color);
    -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4 {
    font-family: var(--font-heading);
    color: var(--text-color);
    letter-spacing: -0.01em;
}

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

img {
    max-width: 100%;
    display: block;
}

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

/* Section rhythm */
.section {
    padding: 5rem 0;
}

@media (max-width: 640px) {
    .section {
        padding: 3.5rem 0;
    }
}

/* Reveal on scroll */
.reveal {
    opacity: 0;
    transform: translateY(18px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.is-visible {
    opacity: 1;
    transform: none;
}

@media (prefers-reduced-motion: reduce) {
    .reveal {
        opacity: 1;
        transform: none;
        transition: none;
    }

    html {
        scroll-behavior: auto;
    }
}