:root {
    --neon-green: #39ff14;
    --carbon-black: #1a1a1a;
    --vibrant-purple: #9b30ff;
    --bg-light: #f8f9fa;
    --border-color: #000000;
    --shadow-color: #000000;
    --border-width: 2px;
    --card-bg: #ffffff;

    /* Global Bootstrap variables overrides to support theme styling */
    --bs-border-radius: 0;
    --bs-border-radius-sm: 0;
    --bs-border-radius-lg: 0;
    --bs-border-radius-xl: 0;
    --bs-border-radius-xxl: 0;
    --bs-border-width: var(--border-width);
    --bs-border-color: var(--border-color);
}

[data-bs-theme='dark'] {
    --bg-light: #121212;
    --carbon-black: #f8f9fa;
    --border-color: #000000; /* Keep borders dark */
    --shadow-color: #000000; /* Keep shadows dark */
    --card-bg: #1e1e1e; /* Slightly lighter than background for contrast */
    --neon-green: #2ea043; /* Softer green for dark mode */
    --vibrant-purple: #8957e5; /* Softer purple for dark mode */
}

[data-bs-theme='dark'] .bg-light {
    background-color: var(--card-bg) !important;
}


/* Unavailable Button styling using Bootstrap's button variables */
.btn-unavailable {
    --bs-btn-bg: transparent;
    --bs-btn-color: #6c757d;
    --bs-btn-border-color: #6c757d;
}

[data-bs-theme='dark'] .btn-unavailable {
    --bs-btn-color: #adb5bd;
    --bs-btn-border-color: #444;
}

.btn-unavailable:hover {
    --bs-btn-hover-bg: rgba(0, 0, 0, 0.05);
    --bs-btn-hover-border-color: #6c757d;
    --bs-btn-hover-color: #6c757d;
}

[data-bs-theme='dark'] .btn-unavailable:hover {
    --bs-btn-hover-bg: rgba(255, 255, 255, 0.05);
    --bs-btn-hover-border-color: #444;
    --bs-btn-hover-color: #adb5bd;
}

html, body {
    font-family: 'Montserrat', sans-serif;
    background-color: var(--bg-light);
    color: var(--carbon-black);
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: -1px;
}

/* Sharp Corners & Bold Borders */
.card, .card-header, .card-footer, .btn, .form-control, .input-group-text, .list-group-item, .alert, .badge {
    border-radius: 0;
    border: var(--border-width) solid var(--border-color);
}

/* Sharp Shadows */
.sharp-shadow {
    box-shadow: 6px 6px 0px var(--shadow-color);
}

.card {
    background-color: var(--card-bg);
    box-shadow: 4px 4px 0px var(--shadow-color);
    margin-bottom: 1.5rem;
}

/* Primary Button Styling (Neon Green) using Bootstrap button variables */
.btn-primary {
    --bs-btn-bg: var(--neon-green);
    --bs-btn-border-color: var(--border-color);
    --bs-btn-color: #000;
    --bs-btn-hover-bg: var(--neon-green);
    --bs-btn-hover-border-color: var(--border-color);
    --bs-btn-hover-color: #000;
    --bs-btn-active-bg: var(--neon-green);
    --bs-btn-active-border-color: var(--border-color);
    --bs-btn-active-color: #000;

    font-weight: 700;
    text-transform: uppercase;
    transition: transform 0.1s;
}

.btn-primary:hover {
    transform: translate(-2px, -2px);
    box-shadow: 4px 4px 0px var(--shadow-color);
}

.btn-primary:active {
    transform: translate(2px, 2px);
    box-shadow: none;
}

/* Secondary/Info Button (Purple) using Bootstrap button variables */
.btn-info {
    --bs-btn-bg: var(--vibrant-purple);
    --bs-btn-border-color: var(--border-color);
    --bs-btn-color: #fff;
    --bs-btn-hover-bg: var(--vibrant-purple);
    --bs-btn-hover-border-color: var(--border-color);
    --bs-btn-hover-color: #fff;
    --bs-btn-active-bg: var(--vibrant-purple);
    --bs-btn-active-border-color: var(--border-color);
    --bs-btn-active-color: #fff;

    font-weight: 700;
}

/* Availability Selection (Checked state) */
.btn-check:checked + .btn-outline-primary {
    background-color: var(--neon-green);
    color: #000;
    border-color: var(--border-color);
    font-weight: 900;
    transform: scale(1.05);
    z-index: 2;
}

/* Unchecked state */
.btn-outline-primary {
    background-color: #fff;
    color: #000;
    border-color: var(--border-color);
    font-weight: 500;
}

[data-bs-theme='dark'] .btn-outline-primary {
    background-color: #222;
    color: #fff;
}

.btn-outline-primary:hover {
    background-color: #eee;
    color: #000;
}

[data-bs-theme='dark'] .btn-outline-primary:hover {
    background-color: #333;
    color: #fff;
}

/* Success Button styling using Bootstrap variables */
.btn-success {
    --bs-btn-bg: var(--neon-green);
    --bs-btn-border-color: var(--border-color);
    --bs-btn-color: #000;
    --bs-btn-hover-bg: var(--neon-green);
    --bs-btn-hover-border-color: var(--border-color);
    --bs-btn-hover-color: #000;
    --bs-btn-active-bg: var(--neon-green);
    --bs-btn-active-border-color: var(--border-color);
    --bs-btn-active-color: #000;

    font-weight: 700;
}

/* Form Inputs */
.form-control:focus {
    box-shadow: 4px 4px 0px var(--neon-green);
    border-color: var(--border-color);
    outline: none;
}

[data-bs-theme='dark'] .form-control {
    background-color: #222;
    color: #fff;
}

/* Layout Adjustments */
.navbar-brand {
    font-weight: 900;
    letter-spacing: -2px;
    font-size: 1.5rem;
    color: var(--neon-green);
}

@media (min-width: 768px) {
    .row-cols-md-7 > * {
        flex: 0 0 auto;
        width: 14.285714%;
    }
}

.card-header {
    background-color: rgba(0, 0, 0, 0.03);
    border-bottom: var(--border-width) solid var(--border-color);
    font-weight: 700;
}

[data-bs-theme='dark'] .card-header {
    background-color: rgba(255, 255, 255, 0.05);
}

/* 
   Bootstrap utility class overrides.
   Note: Bootstrap declares utility classes (like .bg-primary or .text-primary) with !important in its source.
   To override them, we must also use !important.
*/
.bg-primary {
    background-color: var(--neon-green) !important;
    color: #000 !important;
}

.bg-success {
    background-color: var(--neon-green) !important;
    color: #000 !important;
}

.bg-info {
    background-color: var(--vibrant-purple) !important;
    color: #fff !important;
}

.bg-warning {
    background-color: #ffea00 !important;
    color: #000 !important;
}

.text-primary, .text-info {
    color: var(--carbon-black) !important;
    font-weight: 700;
}

/* Hover transitions and highlights for attendee list items */
.list-group-item {
    transition: background-color 0.2s ease, color 0.2s ease;
}

.attendee-highlight-available {
    background-color: var(--neon-green);
    color: #000;
}

.attendee-highlight-available .text-muted,
.attendee-highlight-available small {
    color: rgba(0, 0, 0, 0.6);
}

.attendee-highlight-available .text-primary {
    color: #000;
}

.attendee-highlight-available .badge {
    background-color: #000;
    color: #fff;
    border-color: #000;
}

.attendee-highlight-maybe {
    background-color: var(--vibrant-purple);
    color: #fff;
}

.attendee-highlight-maybe .text-muted,
.attendee-highlight-maybe small {
    color: rgba(255, 255, 255, 0.75);
}

.attendee-highlight-maybe .text-primary {
    color: #fff;
}

.attendee-highlight-maybe .badge {
    background-color: #fff;
    color: #000;
    border-color: #fff;
}

/* Scheduled Event Finalized Box */
.scheduled-time-box {
    background-color: var(--bg-light);
    border: var(--border-width) solid var(--border-color);
    color: var(--carbon-black);
}

.scheduled-date {
    font-weight: 800;
    font-family: 'Montserrat', sans-serif;
}

.scheduled-time {
    color: var(--vibrant-purple);
    font-weight: 700;
}

[data-bs-theme='dark'] .scheduled-time {
    color: var(--neon-green);
}