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

html {
    scroll-behavior: smooth;
    color-scheme: dark;
    overflow-x: hidden;
}

body.light-mode {
    color-scheme: light;
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }
}

body {
    background: var(--bg);
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: 1rem;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    transition: background var(--dur-md) var(--ease), color var(--dur-md) var(--ease);
}

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

.sprite-sheet {
    position: absolute;
    width: 0;
    height: 0;
    overflow: hidden;
}

.icon {
    width: 1em;
    height: 1em;
    fill: none;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
    vertical-align: -0.125em;
    flex-shrink: 0;
    display: inline-block;
}

.icon-brand {
    fill: currentColor;
    stroke: none;
}

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

ul,
ol {
    list-style: none;
}

button {
    font: inherit;
    color: inherit;
    background: none;
    border: none;
    cursor: pointer;
}

h1,
h2,
h3,
h4 {
    line-height: 1.15;
    font-weight: 700;
    letter-spacing: -0.01em;
}

.container {
    width: 100%;
    max-width: var(--container);
    margin-inline: auto;
    padding-inline: var(--gutter);
}

.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 0.5em;
    font-family: var(--font-mono);
    font-size: 0.78rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--accent);
}

.eyebrow::before {
    content: "";
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: currentColor;
}

.section-head {
    max-width: 640px;
    margin-bottom: clamp(2rem, 5vw, 3.5rem);
}

.section-head h2 {
    font-size: clamp(1.7rem, 3.2vw, 2.4rem);
    margin-top: 0.6rem;
}

.section-head p {
    color: var(--text-secondary);
    margin-top: 0.85rem;
    font-size: 1.02rem;
    max-width: 56ch;
}

section {
    position: relative;
    padding-block: clamp(4rem, 9vw, 7rem);
}

[hidden] {
    display: none !important;
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
    white-space: nowrap;
}

.skip-link {
    position: fixed;
    top: -100px;
    left: 1rem;
    z-index: 999;
    background: var(--accent);
    color: #0a0d12;
    padding: 0.7rem 1.1rem;
    border-radius: var(--radius-sm);
    font-weight: 600;
    transition: top var(--dur-sm) var(--ease);
}

.skip-link:focus {
    top: 1rem;
}

:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 3px;
    border-radius: 4px;
}

/* buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    padding: 0.85rem 1.4rem;
    border-radius: var(--radius-sm);
    font-weight: 600;
    font-size: 0.95rem;
    transition: transform var(--dur-sm) var(--ease), border-color var(--dur-sm) var(--ease), background var(--dur-sm) var(--ease);
    border: 1px solid var(--border-strong);
}

.btn:hover {
    transform: translateY(-2px);
}

.btn-primary {
    background: var(--accent);
    color: #06090d;
    border-color: transparent;
}

.btn-primary:hover {
    background: var(--accent-strong);
}

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

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

.tag-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tag {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    letter-spacing: 0.02em;
    padding: 0.3rem 0.65rem;
    border-radius: 999px;
    border: 1px solid var(--border);
    color: var(--text-secondary);
    background: var(--bg-elevated);
    white-space: nowrap;
}

::selection {
    background: var(--accent);
    color: #06090d;
}

/* scroll reveal base */
[data-reveal] {
    opacity: 0;
    transform: translateY(18px);
    transition: opacity var(--dur-lg) var(--ease), transform var(--dur-lg) var(--ease);
}

[data-reveal].is-visible {
    opacity: 1;
    transform: translateY(0);
}

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