/* ============================================================
   Components — Buttons, cards, tags, badges, switches, widgets
   ============================================================ */

/* ---- Buttons ---- */
.btn {
    padding: 14px 28px;
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: transform var(--transition), box-shadow var(--transition),
                background var(--transition), border-color var(--transition),
                color var(--transition);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    border: none;
    letter-spacing: 0.3px;
    white-space: nowrap;
}
.btn:active { transform: translateY(0) scale(0.98); }

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #fff;
    box-shadow: 0 4px 20px rgba(110, 164, 212, 0.3);
    font-size: 15px;
    padding: 16px 32px;
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 32px rgba(110, 164, 212, 0.48);
}

.btn-ghost {
    background: transparent;
    color: var(--text-muted);
    border: 1.5px solid var(--border-strong);
}
.btn-ghost:hover {
    background: rgba(255, 255, 255, 0.04);
    border-color: var(--border-hover);
    color: var(--text-bright);
    transform: translateY(-2px);
}

.btn-channel {
    background: rgba(56, 189, 248, 0.1);
    color: var(--info);
    border: 1.5px solid rgba(56, 189, 248, 0.28);
}
.btn-channel:hover {
    background: rgba(56, 189, 248, 0.2);
    border-color: rgba(56, 189, 248, 0.45);
    transform: translateY(-2px);
}

/* Hub button — violet gradient, the main site link */
.btn-hub {
    background: linear-gradient(135deg, var(--violet), #7c3aed);
    color: #fff;
    box-shadow: 0 4px 20px rgba(167, 139, 250, 0.3);
    font-size: 15px;
    padding: 16px 32px;
}
.btn-hub:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(167, 139, 250, 0.5);
}

/* Neon GitHub button */
.btn-github-neon {
    background: rgba(110, 164, 212, 0.06);
    color: var(--accent);
    border: 1.5px solid rgba(110, 164, 212, 0.5);
    box-shadow: 0 0 15px rgba(110, 164, 212, 0.2),
                inset 0 0 10px rgba(110, 164, 212, 0.05);
    position: relative;
    overflow: hidden;
    animation: neonFlicker 4s infinite alternate;
}
.btn-github-neon::before {
    content: '';
    position: absolute;
    inset: -1px;
    background: linear-gradient(45deg, var(--primary), var(--accent), var(--primary));
    border-radius: var(--radius-md);
    opacity: 0.2;
    z-index: -1;
    filter: blur(6px);
}
.btn-github-neon:hover {
    box-shadow: 0 0 30px rgba(110, 164, 212, 0.45),
                inset 0 0 20px rgba(110, 164, 212, 0.1);
    border-color: var(--accent);
    transform: translateY(-2px);
    color: var(--text-bright);
}

/* ---- Card base ---- */
.card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    transition: border-color var(--transition), transform var(--transition),
                box-shadow var(--transition);
    position: relative;
}

/* ---- Tags ---- */
.tag {
    padding: 5px 12px;
    background: rgba(110, 164, 212, 0.08);
    border: 1px solid rgba(110, 164, 212, 0.18);
    border-radius: var(--radius-sm);
    font-size: 12px;
    color: var(--accent);
    font-weight: 600;
    display: inline-block;
}
.tag-mono {
    font-family: var(--font-mono);
    font-size: 11px;
    padding: 4px 10px;
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    color: var(--text-muted);
    border-radius: 6px;
}
.tag-pill {
    padding: 6px 14px;
    background: rgba(110, 164, 212, 0.08);
    border: 1px solid rgba(158, 200, 232, 0.25);
    border-radius: var(--radius-full);
    font-size: 11px;
    color: var(--accent);
    font-weight: 700;
    font-family: var(--font-mono);
    box-shadow: inset 0 0 12px rgba(158, 200, 232, 0.05),
                0 0 12px rgba(110, 164, 212, 0.08);
    transition: all var(--transition);
}

/* ---- Badge ---- */
.badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 5px 12px;
    background: rgba(110, 164, 212, 0.1);
    border: 1px solid rgba(110, 164, 212, 0.22);
    border-radius: var(--radius-sm);
    font-size: 11px;
    color: var(--accent);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* ---- Language switcher ---- */
.lang-switch {
    position: fixed;
    top: 24px;
    right: 24px;
    z-index: 1000;
    display: flex;
    gap: 4px;
    background: var(--bg-glass);
    padding: 5px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    transition: border-color var(--transition);
}
.lang-switch:hover { border-color: var(--border-hover); }
.lang-btn {
    padding: 8px 16px;
    border: none;
    background: transparent;
    color: var(--text-dim);
    cursor: pointer;
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 13px;
    font-weight: 600;
    transition: all var(--transition);
    letter-spacing: 0.5px;
}
.lang-btn.active {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 4px 15px rgba(110, 164, 212, 0.3);
}
.lang-btn:hover:not(.active) {
    color: var(--text);
    background: rgba(255, 255, 255, 0.05);
}

/* ---- Section header ---- */
.section-header { text-align: center; margin-bottom: 56px; }
.section-label {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 3px;
    color: var(--primary);
    margin-bottom: 16px;
}
.section h2 {
    font-size: clamp(1.8rem, 3.5vw, 2.6rem);
    margin-bottom: 12px;
    letter-spacing: -0.5px;
    color: var(--text-bright);
}
.section-desc {
    color: var(--text-muted);
    font-size: 1.05rem;
    max-width: 520px;
    margin: 0 auto;
    line-height: 1.7;
}

/* ---- Scroll progress indicator ---- */
.scroll-progress {
    position: fixed;
    top: 0; left: 0;
    height: 3px;
    width: 0%;
    background: linear-gradient(90deg, var(--primary), var(--accent), var(--violet));
    z-index: 1500;
    transition: width 0.1s linear;
    box-shadow: 0 0 10px rgba(110, 164, 212, 0.5);
}

/* ---- Back to top button ---- */
.back-to-top {
    position: fixed;
    bottom: 24px;
    right: 24px;
    z-index: 1000;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--bg-glass);
    border: 1px solid var(--border-strong);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    color: var(--accent);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition);
}
.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
.back-to-top:hover {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(110, 164, 212, 0.35);
}