/* ==========================================================
   Components: header, navigation, brand, buttons, tags, cursor
   ========================================================== */

/* ---------- Header ---------- */
.site-header {
  position: fixed;
  top: 0;
  inset-inline: 0;
  z-index: 100;
  padding-top: env(safe-area-inset-top, 0px);
  border-bottom: 1px solid transparent;
  transition: background-color var(--dur-slow) var(--ease-out),
              border-color var(--dur-slow) var(--ease-out),
              transform var(--dur-slow) var(--ease-out);
}
.site-header.is-scrolled {
  background: var(--surface-glass);
  -webkit-backdrop-filter: blur(18px) saturate(140%);
  backdrop-filter: blur(18px) saturate(140%);
  border-bottom-color: var(--border);
}
.site-header.is-hidden { transform: translateY(-100%); }

.site-header__inner {
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: var(--space-6);
}
.site-header__tools { display: flex; align-items: center; gap: var(--space-3); margin-inline-start: auto; }

/* ---------- Brand ---------- */
.brand { display: inline-flex; align-items: center; gap: var(--space-2); flex-shrink: 0; }
.brand__mark { width: 26px; height: 26px; fill: var(--accent); transition: transform var(--dur-slow) var(--ease-spring); }
.brand:hover .brand__mark { transform: rotate(45deg); }
.brand__ar { font-size: 1.25rem; font-weight: 500; letter-spacing: 0.04em; }
.brand__en { font-size: 1.05rem; font-weight: 400; color: var(--text-secondary); letter-spacing: 0.01em; }

/* ---------- Navigation ---------- */
.nav { position: relative; }
.nav__list { display: flex; gap: var(--space-1); }
.nav__link {
  position: relative;
  display: block;
  padding: var(--space-2) var(--space-3);
  font-size: var(--fs-sm);
  font-weight: 400;
  color: var(--text-secondary);
  border-radius: var(--radius-xs);
  transition: color var(--dur-base) var(--ease-out);
}
.nav__link:hover, .nav__link[aria-current="true"] { color: var(--text-primary); }
.nav__indicator {
  position: absolute;
  bottom: -2px;
  left: 0;
  height: 2px;
  width: 0;
  background: var(--accent);
  border-radius: 2px;
  opacity: 0;
  transition: transform var(--dur-slow) var(--ease-out), width var(--dur-slow) var(--ease-out), opacity var(--dur-base);
}
.nav__indicator.is-visible { opacity: 1; }

/* ---------- Buttons ---------- */
.btn {
  --btn-pad-y: 0.85rem;
  --btn-pad-x: 1.6rem;
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--btn-pad-y) var(--btn-pad-x);
  font-size: var(--fs-base);
  font-weight: 400;
  line-height: 1.2;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  isolation: isolate;
  overflow: hidden;
  transition: color var(--dur-base) var(--ease-out),
              border-color var(--dur-base) var(--ease-out),
              background-color var(--dur-base) var(--ease-out),
              transform var(--dur-base) var(--ease-out);
  will-change: transform;
}
.btn--small { --btn-pad-y: 0.55rem; --btn-pad-x: 1.1rem; font-size: var(--fs-sm); }
.btn--large { --btn-pad-y: 1rem; --btn-pad-x: 2rem; }

.btn--solid { background: var(--accent); color: var(--accent-ink); }
.btn--solid::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background: var(--accent-strong);
  clip-path: circle(0% at var(--mx, 50%) var(--my, 50%));
  transition: clip-path var(--dur-slow) var(--ease-out);
}
.btn--solid:hover::before { clip-path: circle(140% at var(--mx, 50%) var(--my, 50%)); }

.btn--ghost { border-color: var(--border-strong); color: var(--text-primary); background: var(--surface); }
.btn--ghost:hover { border-color: var(--accent); background: var(--accent-soft); }

.icon-btn {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  border: 1px solid var(--border);
  color: var(--text-primary);
  transition: border-color var(--dur-base), background-color var(--dur-base);
}
.icon-btn:hover { border-color: var(--border-strong); background: var(--surface-strong); }
.icon { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }

.theme-toggle .icon { grid-area: 1 / 1; transition: transform var(--dur-slow) var(--ease-spring), opacity var(--dur-base); }
.theme-toggle .icon--moon { opacity: 0; transform: rotate(-60deg) scale(0.6); }
:root[data-theme="light"] .theme-toggle .icon--sun { opacity: 0; transform: rotate(60deg) scale(0.6); }
:root[data-theme="light"] .theme-toggle .icon--moon { opacity: 1; transform: none; }

.menu-toggle { display: none; gap: 5px; align-content: center; }
.menu-toggle__bar {
  display: block;
  width: 18px;
  height: 1.5px;
  background: currentColor;
  border-radius: 2px;
  transition: transform var(--dur-base) var(--ease-out);
}
.menu-toggle[aria-expanded="true"] .menu-toggle__bar:first-child { transform: translateY(3.25px) rotate(45deg); }
.menu-toggle[aria-expanded="true"] .menu-toggle__bar:last-child { transform: translateY(-3.25px) rotate(-45deg); }

/* ---------- Text link ---------- */
.text-link {
  background-image: linear-gradient(currentColor, currentColor);
  background-size: 0% 1px;
  background-repeat: no-repeat;
  background-position: 100% 100%;
  padding-bottom: 2px;
  transition: background-size var(--dur-slow) var(--ease-out), color var(--dur-base);
}
.text-link:hover { background-size: 100% 1px; color: var(--accent-strong); }
[dir="ltr"].text-link { background-position: 0 100%; }

/* ---------- Tags ---------- */
.tags { display: flex; flex-wrap: wrap; gap: var(--space-2); }
.tags li {
  font-size: var(--fs-xs);
  padding: 0.3rem 0.75rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border);
  color: var(--text-secondary);
}

/* ---------- Custom cursor (desktop, fine pointer only) ---------- */
.cursor {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 300;
  width: 34px;
  height: 34px;
  margin: -17px 0 0 -17px;
  display: grid;
  place-items: center;
  border: 1px solid var(--accent);
  border-radius: 50%;
  pointer-events: none;
  opacity: 0;
  transform: translate3d(-100px, -100px, 0);
  transition: width var(--dur-base) var(--ease-out), height var(--dur-base) var(--ease-out),
              margin var(--dur-base) var(--ease-out), background-color var(--dur-base),
              border-color var(--dur-base), opacity var(--dur-base);
}
.has-cursor .cursor { opacity: 1; }
.cursor.is-hover { width: 56px; height: 56px; margin: -28px 0 0 -28px; background: var(--accent-soft); }
.cursor.is-label { width: 84px; height: 84px; margin: -42px 0 0 -42px; background: var(--accent); border-color: var(--accent); }
.cursor.is-down { width: 26px; height: 26px; margin: -13px 0 0 -13px; }
.cursor__label {
  font-size: var(--fs-sm);
  font-weight: 500;
  color: var(--accent-ink);
  opacity: 0;
  transform: scale(0.6);
  transition: opacity var(--dur-fast), transform var(--dur-base) var(--ease-spring);
}
.cursor.is-label .cursor__label { opacity: 1; transform: none; }
.cursor.is-hidden { opacity: 0; }