/* MONO — base.css : typography and base element styling */
body {
    font-family: var(--font-sans);
    background: var(--background);
    color: var(--text-primary);
    font-size: 15px;
    transition: background-color var(--duration-base) var(--easing), color var(--duration-base) var(--easing);
}

h1 { font-size: 28px; font-weight: 700; letter-spacing: -0.02em; }
h2 { font-size: 22px; font-weight: 600; letter-spacing: -0.01em; }
h3 { font-size: 17px; font-weight: 600; }
h4 { font-size: 15px; font-weight: 600; }
small, .text-sm { font-size: 13px; }
.text-xs { font-size: 12px; }
.text-secondary { color: var(--text-secondary); }
.text-tertiary { color: var(--text-tertiary); }
.mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }

a.link { color: var(--text-primary); text-decoration: underline; text-underline-offset: 3px; }
a.link:hover { color: var(--text-secondary); }

hr { border: none; border-top: 1px solid var(--border); }

:focus-visible {
    outline: 2px solid var(--focus-ring);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

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

.skip-link {
    position: absolute;
    left: 8px; top: -48px;
    background: var(--text-primary);
    color: var(--background);
    padding: 10px 16px;
    border-radius: var(--radius-sm);
    z-index: 200;
    transition: top var(--duration-fast) var(--easing);
}
.skip-link:focus { top: 8px; }

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

::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: var(--radius-full); }
::-webkit-scrollbar-track { background: transparent; }