/* 리셋 + 레이아웃 프리미티브 */
*, *::before, *::after { box-sizing: border-box; }

html { color-scheme: light dark; }
:root[data-theme="light"] { color-scheme: light; }
:root[data-theme="dark"] { color-scheme: dark; }

body {
    margin: 0;
    font-family: var(--font-sans);
    font-size: var(--fs-14);
    line-height: var(--lh-normal);
    background: var(--surface-page);
    color: var(--text-primary);
    -webkit-font-smoothing: antialiased;
    /* 한국어는 띄어쓰기 단위로만 줄바꿈되게(단어 중간 절단 방지), 끊을 수 없는 긴 토큰만 예외적으로 강제 줄바꿈 */
    word-break: keep-all;
    overflow-wrap: break-word;
}

h1, h2, h3, h4 {
    margin: 0;
    color: var(--text-primary);
    font-weight: 700;
    line-height: var(--lh-tight);
    letter-spacing: var(--tracking-tight);
}
h1 { font-weight: 800; }
p { margin: 0; }

a { color: var(--link-color); text-decoration: none; }
a:hover { text-decoration: underline; }

button, input, select, textarea { font-family: inherit; font-size: inherit; color: inherit; }

:focus-visible {
    outline: 2px solid var(--color-primary-500);
    outline-offset: 2px;
}

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

.icon {
    width: 1em;
    height: 1em;
    fill: none;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
    vertical-align: -0.125em;
}

.page {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-24) var(--space-16) var(--space-64);
}

.page--wide { max-width: 1600px; }

@media (min-width: 640px) {
    .page { padding-left: var(--space-32); padding-right: var(--space-32); }
}

/* --- 상단 내비게이션 --- */
.topnav {
    position: sticky;
    top: 0;
    z-index: var(--z-nav);
    background: var(--surface-card);
    border-bottom: 1px solid var(--border-default);
}

.topnav__inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-16);
    height: var(--topnav-height);
    display: flex;
    align-items: center;
    gap: var(--space-8);
}

.topnav__brand {
    font-weight: 800;
    font-size: var(--fs-16);
    color: var(--text-primary);
    margin-right: var(--space-8);
    white-space: nowrap;
}
.topnav__brand:hover { text-decoration: none; }

.topnav__links {
    display: flex;
    gap: var(--space-4);
    overflow-x: auto;
    flex: 1;
    scrollbar-width: none;
}
.topnav__links::-webkit-scrollbar { display: none; }

.topnav__link {
    padding: var(--space-8) var(--space-12);
    border-radius: var(--radius-8);
    color: var(--text-secondary);
    font-weight: 600;
    font-size: var(--fs-14);
    white-space: nowrap;
    transition: background var(--transition-fast), color var(--transition-fast);
}
.topnav__link:hover { background: var(--surface-sunken); color: var(--text-primary); text-decoration: none; }
.topnav__link.is-active { color: var(--color-primary-500); background: var(--color-primary-100); }

.topnav__badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 18px;
    height: 18px;
    padding: 0 5px;
    margin-left: var(--space-4);
    border-radius: var(--radius-pill);
    background: var(--color-danger);
    color: #fff;
    font-size: 11px;
    font-weight: 700;
    line-height: 18px;
    vertical-align: middle;
}

.topnav__actions {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    margin-left: auto;
}

@media (min-width: 640px) {
    .page { padding-top: var(--space-32); }
}