:root {
    --nav-width: 280px;
    --transition-speed: 0.3s;
    --primary-color: #4b0082; /* Deep Indigo */
    --secondary-color: #6a0dad; /* Royal Purple */
    --accent-color: #9370db; /* Soft Violet */
    --text-color: #e6e6fa; /* Lavender */
    --hover-color: #8a2be2; /* Blue Violet */
    --overlay-color: rgba(0, 0, 0, 0.5);
    --highlight-color: #da70d6; /* Orchid */

    /* Dark mode variables */
    --dark-bg: #1a1a1a;
    --dark-primary: #3a0070;
    --dark-secondary: #52008a;
    --dark-accent: #7a3ebf;
    --dark-text: #dcdcdc;
    --dark-overlay: rgba(0, 0, 0, 0.8);
}

body.dark-mode {
    --primary-color: var(--dark-primary);
    --secondary-color: var(--dark-secondary);
    --accent-color: var(--dark-accent);
    --text-color: var(--dark-text);
    --overlay-color: var(--dark-overlay);
}

/* Reset */
* {
    box-sizing: border-box;
}

/* Hamburger / menu toggle button */
.menu-toggle {
    position: fixed;
    top: 15px;
    left: 15px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    border: none;
    color: var(--text-color);
    font-size: 24px;
    cursor: pointer;
    z-index: 1101;
    padding: 10px;
    border-radius: 50%;
    transition: all var(--transition-speed) ease;
    box-shadow: 0 2px 10px rgba(0,0,0,0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 45px;
    height: 45px;
    cursor: pointer;
}

/* Hamburger icon animation */
.menu-toggle i {
    transition: transform 0.3s ease;
    cursor: pointer;
}

.menu-toggle.open i.fa-bars {
    transform: rotate(90deg);
}

.menu-toggle.open i.fa-times {
    transform: rotate(0deg);
}

.menu-toggle:hover {
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--accent-color) 100%);
    transform: scale(1.1);
}

.menu-toggle:focus {
    outline: none;
    box-shadow: 0 0 0 3px var(--accent-color);
}

/* Sidebar nav */
nav {
    background: linear-gradient(180deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    height: 100vh;
    width: var(--nav-width);
    position: fixed;
    top: 0;
    left: calc(-1 * var(--nav-width));
    transition: left var(--transition-speed) ease-in-out;
    z-index: 1100;
    padding-top: 20px;
    box-shadow: 5px 0 15px rgba(0,0,0,0.2);
    display: flex;
    flex-direction: column;
    border-right: 4px solid var(--accent-color);
    overflow-y: auto;
    -webkit-overflow-scrolling: touch; /* smooth scrolling on iOS */
}

nav.show {
    left: 0;
}

/* Nav header */
.nav-header {
    padding: 15px;
    color: var(--text-color);
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0,0,0,0.1);
    border-bottom: 2px solid var(--accent-color);
    position: relative;
}
.nav-header i {
    margin-right: 10px;
    color: var(--highlight-color);
}

/* Nav links */
nav ul {
    list-style-type: none;
    margin: 0;
    padding: 0;
    flex-grow: 1;
}

nav ul li a {
    color: var(--text-color);
    text-decoration: none;
    padding: 15px 25px;
    display: flex;
    align-items: center;
    transition: all var(--transition-speed) ease;
    position: relative;
    margin: 5px 10px;
    border-radius: 8px;
    font-size: 1rem;
}

nav ul li a:hover {
    background: linear-gradient(90deg, rgba(138, 43, 226, 0.3) 0%, transparent 100%);
    transform: translateX(5px);
}

nav ul li a::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 3px;
    background: var(--highlight-color);
    transform: scaleY(0);
    transition: transform 0.2s ease;
    transform-origin: bottom;
}

nav ul li a:hover::before {
    transform: scaleY(1);
    transform-origin: top;
}

nav ul li a i {
    margin-right: 12px;
    width: 20px;
    text-align: center;
    color: var(--accent-color);
}

/* Active link styling */
nav ul li a.active {
    background: linear-gradient(90deg, rgba(138, 43, 226, 0.4) 0%, transparent 100%);
    border-left: 3px solid var(--highlight-color);
}

nav ul li a.active i {
    color: var(--highlight-color);
}

/* Cart icon badge */
.cart-icon {
    position: relative;
}

.cart-count {
    position: absolute;
    top: -5px;
    right: -3px;
    background: var(--highlight-color);
    color: white;
    border-radius: 50%;
    padding: 3px 7px;
    font-size: 12px;
    font-weight: bold;
    line-height: 1;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

/* Notification badge (for inbox, etc) */
.badge {
    background: var(--highlight-color);
    color: white;
    border-radius: 50%;
    padding: 3px 7px;
    font-size: 12px;
    font-weight: bold;
    line-height: 1;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
    position: absolute;
    top: 10px;
    right: 15px;
}

/* Overlay */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: var(--overlay-color);
    z-index: 1050;
    display: none;
    opacity: 0;
    transition: opacity var(--transition-speed) ease-in-out;
}

.overlay.show {
    display: block;
    opacity: 1;
}

/* Slide-in animation for menu items */
@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

nav.show ul li {
    animation: slideIn 0.3s ease forwards;
}

nav.show ul li:nth-child(1) { animation-delay: 0.1s; }
nav.show ul li:nth-child(2) { animation-delay: 0.15s; }
nav.show ul li:nth-child(3) { animation-delay: 0.2s; }
nav.show ul li:nth-child(4) { animation-delay: 0.25s; }
nav.show ul li:nth-child(5) { animation-delay: 0.3s; }
nav.show ul li:nth-child(6) { animation-delay: 0.35s; }
nav.show ul li:nth-child(7) { animation-delay: 0.4s; }
nav.show ul li:nth-child(8) { animation-delay: 0.45s; }
nav.show ul li:nth-child(9) { animation-delay: 0.5s; }

/* User avatar dropdown */
.user-menu {
    position: relative;
    margin: 5px 10px;
}

.user-menu img#userAvatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    border: 2px solid var(--accent-color);
    transition: box-shadow 0.3s ease;
}

.user-menu img#userAvatar:hover,
.user-menu img#userAvatar:focus {
    box-shadow: 0 0 8px var(--highlight-color);
    outline: none;
}

.user-dropdown {
    display: none;
    position: absolute;
    top: 50px;
    right: 0;
    background: linear-gradient(180deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    border-radius: 8px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    min-width: 160px;
    z-index: 1100;
    flex-direction: column;
    padding: 10px 0;
}

.user-dropdown li {
    list-style: none;
}

.user-dropdown li a {
    color: var(--text-color);
    text-decoration: none;
    padding: 10px 20px;
    display: block;
    transition: background 0.3s ease;
}

.user-dropdown li a:hover {
    background: var(--hover-color);
    color: white;
}

/* Show dropdown when user-menu has .open */
.user-menu.open .user-dropdown {
    display: flex;
}

/* Responsive for tablets and larger phones */
@media (min-width: 480px) and (max-width: 767px) {
    :root {
        --nav-width: 260px;
    }
    nav ul li a {
        padding: 14px 22px;
        font-size: 0.95rem;
    }
    .nav-header {
        font-size: 1.4rem;
        padding: 12px 15px;
    }
}

/* Responsive for mobile phones (smallest screens) */
@media (max-width: 479px) {
    :root {
        --nav-width: 220px;
    }

    nav {
        width: var(--nav-width);
        padding-top: 15px;
        box-shadow: none;
        border-right: none;
        background: var(--primary-color);
    }

    nav ul li a {
        padding: 12px 18px;
        font-size: 0.9rem;
        margin: 5px 5px;
    }

    .nav-header {
        font-size: 1.3rem;
        padding: 10px;
    }

    /* Ensure menu toggle button is visible */
    .menu-toggle {
        display: flex;
        z-index: 1101;
    }

    /* Overlay full screen for mobile */
    .overlay {
        background-color: var(--overlay-color);
        display: none;
        opacity: 0;
        position: fixed;
        top: 0;
        left: 0;
        width: 100vw;
        height: 100vh;
        z-index: 1050;
        transition: opacity var(--transition-speed) ease-in-out;
    }

    .overlay.show {
        display: block;
        opacity: 1;
    }
}

/* For desktop, show nav always and hide menu toggle */
@media (min-width: 768px) {
    .menu-toggle {
        display: none;
    }

    nav {
        left: 0;
        width: var(--nav-width);
        box-shadow: 5px 0 15px rgba(0,0,0,0.2);
    }

    .overlay {
        display: none !important;
    }
}