/* Fixed Top Header - PC Version */
.fixed-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--bg-primary);
    padding: 20px 40px;
    z-index: 999;
    border-bottom: 1px solid var(--border-primary);
    display: flex;
    flex-wrap: nowrap;
    justify-content: space-between;
    align-items: center;
    gap: 8px;
    min-height: auto;
}

.header-content {
    max-width: 1400px;
    margin: 0 auto;
    flex: 1;
}

.title {
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
    letter-spacing: -0.5px;
}

.subtitle {
    font-size: 0.95rem;
    font-weight: 400;
    color: var(--text-secondary);
    display: block;
}

/* Large Desktop: 1440px and up */
@media (min-width: 1440px) {
    .fixed-header {
        padding: 24px 60px;
    }
    
    .title {
        font-size: 2.5rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
}

/* Header Actions */
.header-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

/* Instruments Selector */
.instruments-selector {
    position: relative;
}

.instruments-btn {
    padding: 8px 16px;
    border: none;
    background: var(--bg-secondary);
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    transition: all 0.2s ease;
    font-size: 0.9375rem;
    font-weight: 500;
}

.instruments-btn:hover {
    background: var(--bg-hover);
    transform: translateY(-1px);
}

.instruments-btn-text {
    display: flex;
    align-items: center;
    gap: 6px;
}

/* Instruments Dropdown */
.instruments-dropdown {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    width: 640px;
    max-height: 520px;
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(30px) saturate(180%);
    -webkit-backdrop-filter: blur(30px) saturate(180%);
    border-radius: 20px;
    border: 0.5px solid rgba(255, 255, 255, 0.1);
    box-shadow: 
        0 8px 32px rgba(0, 0, 0, 0.2),
        0 2px 8px rgba(0, 0, 0, 0.1),
        inset 0 1px 0 rgba(255, 255, 255, 0.1);
    z-index: 1000;
    overflow: hidden;
}

.instruments-dropdown.hidden {
    display: none;
}

.instruments-dropdown-content {
    padding: 0;
    max-height: 520px;
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: var(--accent-primary) var(--bg-secondary);
}

.instruments-dropdown-content::-webkit-scrollbar {
    width: 8px;
}

.instruments-dropdown-content::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 4px;
}

.instruments-dropdown-content::-webkit-scrollbar-thumb {
    background: var(--accent-primary);
    border-radius: 4px;
}

.instruments-dropdown-content::-webkit-scrollbar-thumb:hover {
    background: var(--accent-hover);
}

/* Theme Selector */
.theme-selector {
    position: relative;
}

.theme-btn {
    width: 40px;
    height: 40px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.2s ease;
    padding: 0;
}

.theme-btn:hover {
    color: var(--text-primary);
    background: var(--bg-hover);
    transform: scale(1.1);
}

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

/* Theme Dropdown */
.theme-dropdown {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    width: 200px;
    background: var(--bg-secondary);
    border-radius: 8px;
    border: 1px solid var(--border-primary);
    box-shadow: 0 8px 32px var(--shadow-md);
    z-index: 1000;
    overflow: hidden;
}

.theme-dropdown.hidden {
    display: none;
}

.theme-dropdown-header {
    padding: 12px 16px;
    border-bottom: 1px solid var(--border-primary);
}

.theme-dropdown-header span {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.theme-list {
    padding: 8px 0;
}

.theme-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    cursor: pointer;
    transition: background 0.2s ease;
    color: var(--text-primary);
    font-size: 0.9375rem;
}

.theme-item:hover {
    background: var(--bg-hover);
}

.theme-item.active {
    background: var(--bg-hover);
    color: var(--accent-primary);
}

.theme-item-icon {
    font-size: 1.25rem;
    width: 24px;
    text-align: center;
}

.theme-item-name {
    flex: 1;
}

.theme-item-check {
    width: 16px;
    height: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.2s ease;
}

.theme-item.active .theme-item-check {
    opacity: 1;
}

.theme-item-check svg {
    width: 16px;
    height: 16px;
    color: var(--accent-primary);
}