/* Header */
.app-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 56px;
    background-color: var(--surface-color);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 16px;
    z-index: 100;
    box-shadow: 0 1px 0 var(--border-color);
    transition: transform 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    max-width: 600px;
    margin: 0 auto;
}

.app-header.hidden-header {
    transform: translateY(-100%);
}

.header-title {
    font-weight: 700;
    font-size: 18px;
    color: var(--text-primary);
    letter-spacing: -0.3px;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 4px;
}

/* Bottom Navigation - Modern Glass Effect */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: 72px;
    background: var(--nav-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    display: flex;
    justify-content: space-around;
    align-items: center;
    z-index: 100;
    border-top: 1px solid var(--border-color);
    max-width: 600px;
    margin: 0 auto;
    padding: 0 8px;
    padding-bottom: env(safe-area-inset-bottom, 0);
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--nav-inactive);
    font-size: 11px;
    font-weight: 500;
    gap: 4px;
    padding: 8px 16px;
    border-radius: 16px;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    min-width: 64px;
}

.nav-item:active {
    transform: scale(0.92);
}

.nav-item.active {
    color: var(--nav-active);
}

.nav-item.active::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 24px;
    height: 3px;
    background: var(--nav-active);
    border-radius: 0 0 4px 4px;
}

.nav-item svg {
    width: 24px;
    height: 24px;
    stroke-width: 1.5;
    transition: transform 0.2s ease;
}

.nav-item:hover svg {
    transform: translateY(-2px);
}

.nav-item span {
    letter-spacing: 0.2px;
}

/* Fullscreen Layouts (Login/Register) */
.fullscreen-layout {
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-height: 100vh;
    padding: 32px 24px;
    background-color: var(--bg-color);
}

/* Search Modal */
.search-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    display: flex;
    align-items: flex-start;
    justify-content: center;
    padding-top: 60px;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    backdrop-filter: blur(4px);
}

.search-modal.active {
    opacity: 1;
    visibility: visible;
}

.search-modal-content {
    width: 90%;
    max-width: 500px;
    background: var(--card-color);
    border-radius: 16px;
    padding: 16px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    transform: translateY(-20px);
    transition: transform 0.3s ease;
}

.search-modal.active .search-modal-content {
    transform: translateY(0);
}