:root {
    --transition-speed: 0.3s;
}

/* Dark Theme Variables */
[data-bs-theme="dark"] {
    --body-bg: radial-gradient(circle at 10% 20%, rgb(15, 15, 25) 0%, rgb(5, 5, 10) 90.2%);
    --navbar-bg: rgba(20, 20, 30, 0.8);
    --card-bg: rgba(25, 25, 38, 0.6);
    --glass-border: rgba(255, 255, 255, 0.08);
    --text-main: #f7fafc;
    --text-muted: #a0aec0;
    --accent-primary: #8b5cf6; /* Indigo/Purple for frontend */
    --accent-secondary: #ec4899; /* Pink */
    --card-hover-border: rgba(139, 92, 246, 0.4);
    --nav-active-bg: rgba(139, 92, 246, 0.15);
    --input-bg: rgba(255, 255, 255, 0.05);
    --input-bg-focus: rgba(255, 255, 255, 0.08);
    --dropdown-bg: #14141e;
}

/* Light Theme Variables */
[data-bs-theme="light"] {
    --body-bg: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    --navbar-bg: rgba(255, 255, 255, 0.85);
    --card-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(0, 0, 0, 0.08);
    --text-main: #2d3748;
    --text-muted: #4a5568;
    --accent-primary: #7c3aed;
    --accent-secondary: #db2777;
    --card-hover-border: rgba(124, 58, 237, 0.4);
    --nav-active-bg: rgba(124, 58, 237, 0.1);
    --input-bg: rgba(255, 255, 255, 0.7);
    --input-bg-focus: rgba(255, 255, 255, 0.9);
    --dropdown-bg: #ffffff;
}

body {
    font-family: 'Outfit', sans-serif;
    background: var(--body-bg);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background var(--transition-speed) ease, color var(--transition-speed) ease;
}

/* Glassmorphic Navbar */
.glass-navbar {
    background: var(--navbar-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px); /* iOS Safari support */
    border-bottom: 1px solid var(--glass-border);
    z-index: 1050;
    transition: background var(--transition-speed) ease;
}

.brand-link {
    font-weight: 700;
    font-size: 1.5rem;
    text-decoration: none;
    background: linear-gradient(45deg, var(--accent-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    display: flex;
    align-items: center;
}

/* Cards and premium boxes */
.glass-card {
    background: var(--card-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.glass-card:hover {
    border-color: var(--card-hover-border);
    transform: translateY(-2px);
}

/* Shared Book Card Cover Styles */
.book-cover-shared {
    position: relative;
    border-radius: 6px !important;
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.25);
    transition: transform 0.4s ease, box-shadow 0.4s ease;
    overflow: hidden;
    aspect-ratio: 3/4;
    background: #1a1a2e;
    will-change: transform, box-shadow;
}

.book-cover-shared .book-cover-img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
    will-change: transform;
}

/* Buttons styling */
.btn-premium {
    background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 100%);
    color: white !important;
    border: none;
    font-weight: 600;
    padding: 10px 24px;
    border-radius: 12px;
    transition: all 0.3s ease;
}

.btn-premium:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.4);
}

.btn-outline-premium {
    background: transparent;
    border: 1px solid var(--accent-primary);
    color: var(--text-main);
    font-weight: 600;
    padding: 9px 23px;
    border-radius: 12px;
    transition: all 0.3s ease;
}

.btn-outline-premium:hover {
    background: var(--accent-primary);
    color: white !important;
    transform: translateY(-2px);
}

/* Custom inputs */
.form-control, .form-select {
    background-color: var(--input-bg) !important;
    border-color: var(--glass-border) !important;
    color: var(--text-main) !important;
    border-radius: 10px;
}

.form-control:focus, .form-select:focus {
    background-color: var(--input-bg-focus);
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 0.25rem rgba(139, 92, 246, 0.2);
}

/* Custom dropdowns */
.glass-dropdown {
    background: var(--dropdown-bg) !important;
    border: 1px solid var(--glass-border) !important;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25) !important;
    border-radius: 12px !important;
}

.glass-dropdown .dropdown-item {
    color: var(--text-main) !important;
    transition: all 0.2s ease;
}

.glass-dropdown .dropdown-item:hover {
    background: var(--nav-active-bg) !important;
    color: var(--accent-primary) !important;
    transform: translateX(3px);
}

/* Dark / Light Toggle Button */
.theme-toggle-btn {
    background: transparent;
    border: 1px solid var(--glass-border);
    color: var(--text-main);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    cursor: pointer;
}

.theme-toggle-btn:hover {
    background: rgba(255, 255, 255, 0.08);
    transform: rotate(15deg);
}

/* Typography spacing & overrides */
.text-muted {
    color: var(--text-muted) !important;
}

/* iOS Safari optimization */
@supports (-webkit-touch-callout: none) {
    body {
        /* prevent scrolling bounce on iOS Safari */
        -webkit-overflow-scrolling: touch;
    }
}
/* Floating Theme Toggle Button */
.floating-theme-toggle {
    position: fixed;
    bottom: 25px;
    right: 25px;
    z-index: 1060;
    background: var(--card-bg, rgba(25, 25, 38, 0.85));
    border: 1px solid var(--glass-border, rgba(255, 255, 255, 0.15));
    color: var(--text-main);
    border-radius: 50%;
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    cursor: pointer;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.floating-theme-toggle:hover {
    transform: scale(1.1) rotate(15deg);
    background: var(--accent-primary);
    color: #fff;
    box-shadow: 0 6px 20px rgba(139, 92, 246, 0.4);
}
/* Custom notification dropdown item styles */
.notification-item.unread {
    background: rgba(139, 92, 246, 0.06);
}
.notification-item:hover {
    background: var(--nav-active-bg, rgba(139, 92, 246, 0.15)) !important;
}
/* APK Promo Banner Styling (Default/Dark) */
.apk-banner {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.15) 0%, rgba(139, 92, 246, 0.15) 100%);
    border: 1px solid rgba(139, 92, 246, 0.25);
    border-radius: 16px;
    position: relative;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
}
.apk-banner::before {
    content: "";
    position: absolute;
    top: -50%;
    right: -10%;
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, rgba(139, 92, 246, 0.2) 0%, rgba(0,0,0,0) 70%);
    z-index: 1;
    pointer-events: none;
}
.apk-banner .banner-title {
    color: #ffffff !important;
}
.apk-banner .banner-text {
    color: #a0aec0 !important;
}
.apk-banner .banner-subtext {
    color: #718096 !important;
}
.apk-banner .banner-badge {
    font-size: 0.8rem;
    font-weight: 600;
    background: rgba(139, 92, 246, 0.2) !important;
    border: 1px solid rgba(139, 92, 246, 0.35) !important;
    color: #c084fc !important;
}

/* Light Theme Overrides */
[data-bs-theme="light"] .apk-banner {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.08) 0%, rgba(139, 92, 246, 0.08) 100%);
    border: 1px solid rgba(99, 102, 241, 0.18);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
}
[data-bs-theme="light"] .apk-banner .banner-title {
    color: #1a202c !important;
}
[data-bs-theme="light"] .apk-banner .banner-text {
    color: #4a5568 !important;
}
[data-bs-theme="light"] .apk-banner .banner-subtext {
    color: #718096 !important;
}
[data-bs-theme="light"] .apk-banner .banner-badge {
    background: rgba(99, 102, 241, 0.1) !important;
    border: 1px solid rgba(99, 102, 241, 0.25) !important;
    color: #4f46e5 !important;
}
.apk-btn {
    background: linear-gradient(135deg, #8b5cf6 0%, #6366f1 100%);
    border: none;
    color: white !important;
    font-weight: 600;
    padding: 10px 24px;
    border-radius: 30px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.4);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}
.apk-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(139, 92, 246, 0.6);
}

.win-btn {
    background: linear-gradient(135deg, #06b6d4 0%, #3b82f6 100%);
    border: none;
    color: white !important;
    font-weight: 600;
    padding: 10px 24px;
    border-radius: 30px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(6, 182, 212, 0.4);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}
.win-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(6, 182, 212, 0.6);
}

.ios-btn {
    background: linear-gradient(135deg, #1e1e24 0%, #2a2a35 100%);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: white !important;
    font-weight: 600;
    padding: 10px 24px;
    border-radius: 30px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}
[data-bs-theme="light"] .ios-btn {
    background: linear-gradient(135deg, #000000 0%, #1c1c1e 100%);
    border-color: rgba(0, 0, 0, 0.2);
}
.ios-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.4);
}

@media (max-width: 575.98px) {
    .apk-btn, .win-btn, .ios-btn {
        width: 100% !important;
        display: flex !important;
        justify-content: center !important;
    }
}

/* Custom Mobile Navbar Optimization */
@media (max-width: 991.98px) {
    .navbar-collapse {
        background: var(--navbar-bg) !important;
        backdrop-filter: blur(25px) !important;
        -webkit-backdrop-filter: blur(25px) !important;
        border-top: 1px solid var(--glass-border) !important;
        padding: 0.35rem 0.75rem !important;
        margin-top: 5px !important;
    }

    .navbar-nav {
        margin-bottom: 1rem !important;
        gap: 5px;
    }

    .navbar-nav .nav-link {
        padding: 0.6rem 1rem !important;
        border-radius: 10px !important;
        color: var(--text-main) !important;
        display: flex;
        align-items: center;
        font-weight: 500;
    }

    .navbar-nav .nav-link:hover, .navbar-nav .nav-link:focus {
        background: var(--nav-active-bg) !important;
        color: var(--accent-primary) !important;
    }

    /* Search Form */
    .navbar-collapse form {
        max-width: 100% !important;
        margin: 0 !important;
    }
    .navbar-collapse form .form-control {
        padding: 0.45rem 0.9rem !important;
        font-size: 0.85rem !important;
        height: 38px !important;
    }
    .navbar-collapse form .btn {
        padding: 0.45rem 0.75rem !important;
        font-size: 0.85rem !important;
        height: 38px !important;
        display: inline-flex !important;
        align-items: center !important;
        justify-content: center !important;
    }

    /* Right menu on mobile */
    .navbar-collapse .d-flex.align-items-center.gap-2 {
        width: 100%;
        justify-content: flex-start !important;
        gap: 12px !important;
        padding-top: 15px;
        border-top: 1px dashed var(--glass-border);
    }

    .navbar-collapse .theme-toggle-btn {
        border-radius: 50% !important;
        width: 42px !important;
        height: 42px !important;
        display: flex !important;
        justify-content: center !important;
        align-items: center !important;
        background: rgba(255, 255, 255, 0.05) !important;
        border: 1px solid var(--glass-border) !important;
    }
    [data-bs-theme="dark"] .navbar-collapse .theme-toggle-btn {
        background: rgba(0, 0, 0, 0.03) !important;
    }

    .navbar-collapse .dropdown .btn-outline-premium {
        border-radius: 20px !important;
        padding: 8px 16px !important;
        font-size: 0.85rem !important;
        height: 42px !important;
        width: auto !important;
        display: inline-flex !important;
        align-items: center !important;
        justify-content: center !important;
    }
}