/* ============================================================
   Need IT 官網 — 自訂導覽列
   取代 Weebly 佈景的 unite-header，行為完全自控。
   ============================================================ */

:root {
  --nit-nav-h:        84px;   /* 桌機版頁首高度 */
  --nit-nav-h-mobile: 64px;
  --nit-text:         #333;
  --nit-accent:       #24678d;
  --nit-border:       #e6e6e6;
  --nit-bg:           #fff;
  --nit-max:          1400px;
}

/* ── 版面骨架 ────────────────────────────────────────────── */

.nit-header {
  position: sticky;
  top: 0;
  z-index: 9999;
  background: var(--nit-bg);
  border-bottom: 1px solid var(--nit-border);
}

.nit-header__inner {
  max-width: var(--nit-max);
  margin: 0 auto;
  padding: 0 24px;
  height: var(--nit-nav-h);
  display: flex;
  align-items: center;
  gap: 24px;
}

.nit-logo {
  flex: 0 0 auto;
  display: block;
  line-height: 0;
}

.nit-logo img {
  height: 56px;
  width: auto;
  display: block;
}

/* ── 選單 ────────────────────────────────────────────────── */

.nit-nav {
  flex: 1 1 auto;
  min-width: 0;              /* 允許收縮，overflow 偵測才會生效 */
}

.nit-nav__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: nowrap;         /* 不換行，改用「更多…」收合 */
  justify-content: center;
  align-items: center;
  gap: 26px;
  overflow: hidden;          /* 配合 scrollWidth 判斷是否溢位 */
}

.nit-nav__item { flex: 0 0 auto; }

.nit-nav__link {
  display: block;
  padding: 6px 0;
  color: var(--nit-text);
  font-size: 15px;
  font-weight: 500;
  line-height: 1.4;
  text-decoration: none;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  transition: color .18s, border-color .18s;
}

.nit-nav__link:hover { color: var(--nit-accent); }

.nit-nav__item.is-active > .nit-nav__link {
  color: var(--nit-accent);
  border-bottom-color: var(--nit-accent);
}

/* ── 「更多…」收合選單 ──────────────────────────────────── */

.nit-nav__more { position: relative; flex: 0 0 auto; }
.nit-nav__more[hidden] { display: none; }

.nit-nav__more-btn {
  background: none;
  border: 0;
  padding: 6px 0;
  font: inherit;
  font-size: 15px;
  font-weight: 500;
  color: var(--nit-text);
  cursor: pointer;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
}

.nit-nav__more-btn::after {
  content: '';
  display: inline-block;
  margin-left: 6px;
  border: 4px solid transparent;
  border-top-color: currentColor;
  transform: translateY(2px);
}

.nit-nav__more-btn:hover { color: var(--nit-accent); }

.nit-nav__more.is-active > .nit-nav__more-btn {
  color: var(--nit-accent);
  border-bottom-color: var(--nit-accent);
}

.nit-nav__more-list {
  list-style: none;
  margin: 0;
  padding: 8px 0;
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  min-width: 220px;
  background: var(--nit-bg);
  border: 1px solid var(--nit-border);
  box-shadow: 0 8px 24px rgba(0, 0, 0, .1);
  display: none;
}

.nit-nav__more[aria-expanded='true'] .nit-nav__more-list { display: block; }

.nit-nav__more-list .nit-nav__link {
  padding: 11px 20px;
  border-bottom: 0;
}

.nit-nav__more-list .nit-nav__link:hover { background: #f5f7f9; }

.nit-nav__more-list .nit-nav__item.is-active > .nit-nav__link {
  border-bottom: 0;
  background: #f5f7f9;
}

/* ── 手機版 ──────────────────────────────────────────────── */

.nit-burger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  margin-left: auto;
  padding: 0;
  background: none;
  border: 0;
  cursor: pointer;
}

.nit-burger span {
  display: block;
  width: 24px;
  height: 2px;
  margin: 0 auto;
  background: var(--nit-text);
  transition: transform .2s, opacity .2s;
}

.nit-header.is-open .nit-burger span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nit-header.is-open .nit-burger span:nth-child(2) { opacity: 0; }
.nit-header.is-open .nit-burger span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

@media (max-width: 980px) {
  .nit-header__inner { height: var(--nit-nav-h-mobile); padding: 0 16px; }
  .nit-logo img      { height: 42px; }
  .nit-burger        { display: flex; }

  .nit-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--nit-bg);
    border-bottom: 1px solid var(--nit-border);
    box-shadow: 0 8px 24px rgba(0, 0, 0, .08);
    max-height: calc(100vh - var(--nit-nav-h-mobile));
    overflow-y: auto;
  }

  .nit-header.is-open .nit-nav { display: block; }

  .nit-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    overflow: visible;        /* 手機版不收合，全部展開 */
  }

  .nit-nav__item { border-top: 1px solid #f0f0f0; }
  .nit-nav__item:first-child { border-top: 0; }

  .nit-nav__link {
    padding: 15px 20px;
    border-bottom: 0;
  }

  .nit-nav__item.is-active > .nit-nav__link {
    border-bottom: 0;
    background: #f5f7f9;
  }

  .nit-nav__more { display: none !important; }
}

/* 未套用 JS 時（或 JS 失效）仍看得到完整選單 */
.nit-nav__list.is-measuring { visibility: hidden; }