/* =========================
   HEADER
========================= */

.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;

    background: var(--header-glass-bg);

    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);

    border-bottom: 1px solid var(--header-glass-border);

    transition:
        background-color 0.3s ease,
        box-shadow 0.3s ease,
        border-color 0.3s ease;
}

/* =========================
   SCROLLED STATE
========================= */

.site-header.scrolled {
    background: var(--header-glass-bg-solid);

    box-shadow: var(--shadow-sm);

    border-bottom:
        1px solid rgba(var(--color-primary-rgb), 0.08);
}

/* =========================
   LAYOUT
========================= */

.header-container {
    position: relative;

    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;

    min-height: 92px;

    transition: min-height 0.3s ease;
}

.site-header.scrolled .header-container {
    min-height: 78px;
}

/* =========================
   BRAND
========================= */

.brand {
    display: flex;
    align-items: center;
    gap: 14px;

    text-decoration: none;
}

.brand-image img {
    width: 64px;
    height: 64px;

    border-radius: 50%;
    object-fit: cover;

    border: 2px solid var(--color-light);

    transition: transform 0.3s ease;
}

.site-header.scrolled .brand-image img {
    transform: scale(0.92);
}

.brand-title {
    font-family: 'Poppins', sans-serif;
    font-size: 1.15rem;
    font-weight: 600;
    line-height: 1.2;

    color: var(--color-heading);

    transition: font-size 0.3s ease;
}

.site-header.scrolled .brand-title {
    font-size: 1.05rem;
}

.brand-subtitle {
    display: block;

    font-size: 0.85rem;
    font-weight: 500;

    color: var(--color-text-muted);
}

/* =========================
   NAVIGATION
========================= */

.main-nav {
    position: relative;
    display: inline-block;
}

.main-nav ul {
    display: flex;
    align-items: center;
    gap: 26px;

    margin: 0;
    padding: 0;

    list-style: none;
}

.main-nav a {
    position: relative;

    text-decoration: none;

    font-size: 0.95rem;
    font-weight: 500;

    color: var(--color-text-dark);

    padding: 8px 2px;

    transition:
        color 0.25s ease,
        opacity 0.25s ease;
}

.main-nav a:hover {
    color: var(--color-primary);
    opacity: 0.9;
}

.main-nav a.active {
    color: var(--color-primary);
    text-shadow: 0 0 10px rgba(var(--color-primary-rgb), 0.12);
}

/* =========================
   ACTIVE INDICATOR
========================= */

.nav-indicator {
    position: absolute;
    left: 0;
    bottom: 0;

    height: 2px;

    background: linear-gradient(
        90deg,
        var(--color-primary-solid),
        var(--color-primary-light)
    );

    border-radius: 999px;

    transition:
        transform 0.4s cubic-bezier(0.25, 1, 0.5, 1),
        width 0.35s ease;

    will-change:
        transform,
        width;

    box-shadow:
        0 0 10px rgba(var(--color-primary-rgb), 0.2);
}

/* =========================
   THEME TOGGLE
========================= */

.theme-toggle {
    display: flex;
    align-items: center;
    justify-content: center;

    /* Impinge theme-toggle (si tot ce urmeaza dupa el in ordinea
       din HTML: nav-toggle, nav) spre dreapta, grupat, in loc sa fie
       distribuit la mijloc de justify-content: space-between de pe
       .header-container. */
    margin-left: auto;

    width: 40px;
    height: 40px;

    padding: 8px;

    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: 999px;
    cursor: pointer;

    color: var(--color-text-dark);

    transition:
        background-color var(--transition-fast),
        border-color var(--transition-fast),
        color var(--transition-fast),
        transform var(--transition-fast);
}

.theme-toggle:hover,
.theme-toggle:focus-visible {
    background: var(--color-alt-surface);
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.theme-toggle:active {
    transform: scale(0.92);
}

.theme-toggle-icon {
    width: 20px;
    height: 20px;
}

/* Implicit (tema deschisa): luna vizibila — "apasa ca sa treci la
   tema intunecata". Soarele apare doar cand tema activa e dark. */
.theme-toggle-icon-sun {
    display: none;
}

.theme-toggle-icon-moon {
    display: block;
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) .theme-toggle-icon-sun {
        display: block;
    }

    :root:not([data-theme="light"]) .theme-toggle-icon-moon {
        display: none;
    }
}

:root[data-theme="dark"] .theme-toggle-icon-sun {
    display: block;
}

:root[data-theme="dark"] .theme-toggle-icon-moon {
    display: none;
}

/* =========================
   MOBILE MENU TOGGLE
========================= */

.nav-toggle {
    display: none;

    flex-direction: column;
    justify-content: center;
    gap: 5px;

    width: 40px;
    height: 40px;

    padding: 8px;

    background: transparent;
    border: none;
    cursor: pointer;

    z-index: 1001;
}

.nav-toggle-bar {
    display: block;

    width: 100%;
    height: 2px;

    background: var(--color-heading);
    border-radius: 999px;

    transition:
        transform 0.3s ease,
        opacity 0.3s ease;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) {
    opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* =========================
   TABLET
========================= */

@media (max-width: 992px) {

    .header-container {
        min-height: 84px;
    }

    .site-header.scrolled .header-container {
        min-height: 72px;
    }

    .brand-image img {
        width: 56px;
        height: 56px;
    }

    .brand-title {
        font-size: 1rem;
    }

    .brand-subtitle {
        font-size: 0.8rem;
    }
}

/* =========================
   MOBILE NAV
========================= */

@media (max-width: 768px) {

    .nav-toggle {
        display: flex;
    }

    .main-nav {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;

        max-height: 0;
        overflow: hidden;

        background: var(--header-glass-bg-solid);
        backdrop-filter: blur(14px);

        border-bottom: 1px solid var(--header-glass-border-solid);

        transition: max-height 0.35s ease;
    }

    .main-nav.open {
        max-height: 400px;
    }

    .main-nav ul {
        flex-direction: column;
        align-items: stretch;

        gap: 0;

        padding: 12px 0;
    }

    .main-nav a {
        display: block;

        padding: 14px 24px;
        font-size: 1rem;
    }

    .nav-indicator {
        display: none;
    }
}

/* =========================
   MOTION ACCESSIBILITY
========================= */

@media (prefers-reduced-motion: reduce) {

    .site-header,
    .header-container,
    .brand-image img,
    .brand-title,
    .main-nav,
    .main-nav a,
    .nav-indicator,
    .nav-toggle-bar {
        transition: none !important;
    }
}