/* Sidebar default: hidden on mobile */
.app-sidebar {
    display: none;
}
.app-layout {
    display: block;
}
.app-main {
    width: 100%;
}

/* Desktop Sidebar: shown on screen sizes 1080px and wider */
@media (min-width: 1080px) {
    .app-layout {
        display: flex;
        height: 100vh;
        background-color: #f8fafc;
        overflow: hidden;
    }
    .app-main {
        flex: 1;
        min-width: 0;
        margin-left: 280px; /* Leave space for the fixed sidebar */
        height: 100vh;
        display: flex;
        flex-direction: column;
        overflow: hidden;
    }
    .app-sidebar {
        display: flex;
        width: 280px;
        background: linear-gradient(180deg, #12093a 0%, #211456 100%);
        color: #ffffff;
        font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
        flex-direction: column;
        padding: 0;
        flex-shrink: 0;
        position: fixed; /* Keep locked in place */
        left: 0;
        top: 0;
        height: 100vh;
        overflow-y: hidden; /* Sidebar content always fits 100vh; auto caused scrollbar flicker on ChordTrainer */
        box-shadow: 4px 0 20px rgba(0, 0, 0, 0.15);
        z-index: 100;
    }
    
    .sidebar-brand {
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        padding: 30px 20px;
        border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }
    .brand-logo {
        width: 140px;
        height: 140px;
        border-radius: 32px;
        object-fit: cover;
        box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
        transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    }
    .brand-logo:hover {
        transform: scale(1.06);
    }
    .brand-text-logo {
        width: 210px;
        height: auto;
        margin-top: 14px;
        border-radius: 9999px;
        overflow: hidden;
        transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    }
    .brand-text-logo:hover {
        transform: scale(1.04);
    }

    /* Nav menu items */
    .sidebar-nav {
        display: flex;
        flex-direction: column;
        gap: 4px;
        padding: 20px 12px;
    }
    .nav-item {
        display: flex;
        align-items: center;
        gap: 12px;
        padding: 12px 16px;
        color: #c7d2fe;
        text-decoration: none;
        font-size: 14px;
        font-weight: 600;
        line-height: 1.6; /* Explicit: prevents inheriting different line-height from each page's body */
        border-radius: 10px;
        transition: all 0.2s ease;
    }
    .nav-item:hover {
        background: rgba(255, 255, 255, 0.06);
        color: #ffffff;
    }
    .nav-item.active {
        background: linear-gradient(135deg, #6366f1 0%, #4f46e5 100%);
        color: #ffffff;
        box-shadow: 0 4px 12px rgba(79, 70, 229, 0.3);
    }
    .nav-icon {
        font-size: 18px;
        width: 24px;
        text-align: center;
    }

    /* Playlists section */
    .sidebar-section {
        padding: 9px 16px 18px;
        border-top: 1px solid rgba(255, 255, 255, 0.08);
    }
    .section-header {
        display: flex;
        align-items: center;
        justify-content: space-between;
        font-size: 11px;
        font-weight: 700;
        text-transform: uppercase;
        letter-spacing: 0.08em;
        color: rgba(255, 255, 255, 0.4);
        margin-bottom: 12px;
        padding: 0 12px;
    }
    .add-playlist-btn {
        background: transparent;
        border: none;
        color: rgba(255, 255, 255, 0.6);
        font-size: 16px;
        cursor: pointer;
        padding: 0;
        line-height: 1;
        transition: color 0.2s;
    }
    .add-playlist-btn:hover {
        color: #ffffff;
    }
    .playlist-items {
        display: flex;
        flex-direction: column;
        gap: 4px;
    }
    .playlist-item {
        display: flex;
        align-items: center;
        gap: 12px;
        padding: 8px 12px;
        color: #c7d2fe;
        text-decoration: none;
        border-radius: 8px;
        transition: all 0.2s ease;
    }
    .playlist-item:hover {
        background: rgba(255, 255, 255, 0.04);
        color: #ffffff;
    }
    .playlist-item.active {
        background: rgba(255, 255, 255, 0.1);
        color: #ffffff;
        font-weight: 700;
    }
    .playlist-icon {
        width: 28px;
        height: 28px;
        border-radius: 6px;
        object-fit: cover;
        opacity: 0.8;
    }
    .playlist-info {
        display: flex;
        flex-direction: column;
    }
    .playlist-name {
        font-size: 13px;
        font-weight: 600;
        line-height: 1.2;
    }
    .playlist-count {
        font-size: 10px;
        color: rgba(255, 255, 255, 0.45);
    }

    /* Upgrade Card (Pro) */
    .pro-card {
        margin: auto 16px 20px;
        background: linear-gradient(135deg, rgba(255, 255, 255, 0.05) 0%, rgba(255, 255, 255, 0.02) 100%);
        border: 1px solid rgba(255, 255, 255, 0.08);
        backdrop-filter: blur(10px);
        padding: 16px;
        border-radius: 16px;
        text-align: center;
    }
    .pro-badge {
        font-size: 12px;
        font-weight: 700;
        color: #fbbf24;
        text-transform: uppercase;
        letter-spacing: 0.05em;
        margin-bottom: 8px;
    }
    .pro-text {
        font-size: 11px;
        color: rgba(255, 255, 255, 0.7);
        line-height: 1.4;
        margin: 0 0 12px;
    }
    .pro-btn {
        width: 100%;
        background: linear-gradient(135deg, #6366f1 0%, #4f46e5 100%);
        border: none;
        color: #ffffff;
        padding: 10px;
        border-radius: 10px;
        font-size: 13px;
        font-weight: 700;
        cursor: pointer;
        box-shadow: 0 4px 12px rgba(79, 70, 229, 0.2);
        transition: all 0.2s;
    }
    .pro-btn:hover {
        transform: translateY(-1px);
        box-shadow: 0 6px 16px rgba(79, 70, 229, 0.3);
    }
}

/* Stack of CDs/Records for My Library */
.cd-stack {
    position: relative;
    display: inline-flex !important;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
}
.cd-stack .cd-item {
    position: absolute;
    font-size: 14px;
    line-height: 1;
}
.cd-stack .cd-item:nth-child(1) {
    transform: translate(3px, 3px);
    z-index: 1;
    opacity: 0.6;
}
.cd-stack .cd-item:nth-child(2) {
    transform: translate(0px, 0px);
    z-index: 2;
    opacity: 0.85;
}
.cd-stack .cd-item:nth-child(3) {
    transform: translate(-3px, -3px);
    z-index: 3;
}