:root {
    --primary: #c2ff47; /* Neon Pickleball Green */
    --primary-hover: #a1d830;
    --bg-dark: #121212;
    --bg-card: #1e1e1e;
    --text-light: #f5f5f5;
    --text-muted: #a0a0a0;
    --danger: #ff4757;
    --radius: 12px;
    --transition: 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Outfit', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-light);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Typography */
h1, h2, h3 {
    font-weight: 800;
    line-height: 1.2;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

/* Navigation */
.navbar {
    background: rgba(18, 18, 18, 0.8);
    backdrop-filter: blur(10px);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
}

.logo span {
    color: var(--primary);
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    font-weight: 600;
}

.nav-links a:hover {
    color: var(--primary);
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    flex-direction: column;
    gap: 5px;
}

.menu-toggle span {
    width: 25px;
    height: 3px;
    background: var(--text-light);
    border-radius: 2px;
    transition: var(--transition);
}

/* Main Content */
main {
    flex: 1;
}

/* Hero Section */
.hero {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 4rem 2rem;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(194, 255, 71, 0.05) 0%, rgba(18, 18, 18, 0) 50%);
    z-index: -1;
}

.hero-img {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid var(--primary);
    box-shadow: 0 0 20px rgba(194, 255, 71, 0.3);
    margin-bottom: 2rem;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.2rem;
    color: var(--text-muted);
    max-width: 600px;
    margin-bottom: 2.5rem;
}

/* Buttons */
.btn {
    display: inline-block;
    background: var(--primary);
    color: var(--bg-dark);
    padding: 1rem 2.5rem;
    border-radius: 50px;
    font-weight: 800;
    font-size: 1.1rem;
    box-shadow: 0 4px 15px rgba(194, 255, 71, 0.4);
    border: none;
    cursor: pointer;
}

.btn:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(194, 255, 71, 0.6);
}

.btn:disabled {
    background: #444;
    color: #888;
    box-shadow: none;
    cursor: not-allowed;
    transform: none;
}

/* Sections & Cards */
.section-container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 4rem 2rem;
}

.card {
    background: var(--bg-card);
    border-radius: var(--radius);
    padding: 2rem;
    border: 1px solid rgba(255, 255, 255, 0.05);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

/* Forms & Calendar */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-muted);
}

.form-control {
    width: 100%;
    padding: 1rem;
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    color: var(--text-light);
    font-family: inherit;
    font-size: 1rem;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(194, 255, 71, 0.2);
}

.slots-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}

.slot-btn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-light);
    padding: 1rem;
    border-radius: 8px;
    cursor: pointer;
    text-align: center;
    transition: var(--transition);
}

.slot-btn:hover:not(:disabled) {
    border-color: var(--primary);
    background: rgba(194, 255, 71, 0.1);
}

.slot-btn.selected {
    background: var(--primary);
    color: var(--bg-dark);
    font-weight: bold;
}

.slot-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    background: rgba(0, 0, 0, 0.3);
}

/* Messages */
.msg {
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
    font-weight: 600;
}
.msg.success { background: rgba(194, 255, 71, 0.2); color: var(--primary); border: 1px solid var(--primary); }
.msg.error { background: rgba(255, 71, 87, 0.2); color: var(--danger); border: 1px solid var(--danger); }

/* Calendar Grid Layout */
.booking-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    align-items: start;
}

.calendar-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.btn-icon {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-light);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.btn-icon:hover {
    background: var(--primary);
    color: var(--bg-dark);
    border-color: var(--primary);
}

.calendar-days-header {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    text-align: center;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-muted);
}

.calendar-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 8px;
}

.calendar-day {
    min-height: 120px;
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 8px;
    padding: 0.5rem;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.calendar-day:hover:not(.disabled) {
    border-color: var(--primary);
    background: rgba(194, 255, 71, 0.05);
}

.calendar-day.selected {
    border-color: var(--primary);
    box-shadow: 0 0 10px rgba(194, 255, 71, 0.2);
}

.calendar-day.disabled {
    opacity: 0.5;
    cursor: not-allowed;
    background: transparent;
}

.day-number {
    font-weight: 800;
    font-size: 1.2rem;
    margin-bottom: 0.2rem;
}

.day-indicators {
    font-size: 0.75rem;
    display: flex;
    flex-direction: column;
    gap: 3px;
    flex: 1;
}

.indicator {
    padding: 2px 4px;
    border-radius: 4px;
    background: rgba(255, 255, 255, 0.1);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    display: flex;
    flex-direction: column;
}

.indicator.has-spots {
    background: rgba(194, 255, 71, 0.15);
    color: var(--primary);
}

.indicator.full {
    background: rgba(255, 71, 87, 0.15);
    color: var(--danger);
}

.student-name {
    font-size: 0.65rem;
    color: var(--text-muted);
    line-height: 1.1;
}

/* Modal Styles */
.modal {
    display: none; /* Hidden by default */
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(5px);
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: var(--bg-card);
    margin: auto;
    padding: 2rem;
    border: 1px solid rgba(255, 255, 255, 0.1);
    width: 90%;
    max-width: 500px;
    border-radius: var(--radius);
    position: relative;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
    animation: modalSlideIn 0.3s ease;
    max-height: 90vh;
    overflow-y: auto;
}

@keyframes modalSlideIn {
    from { transform: translateY(-50px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.close-btn {
    color: var(--text-muted);
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    transition: var(--transition);
    line-height: 1;
    position: absolute;
    top: 15px;
    right: 20px;
}

.close-btn:hover,
.close-btn:focus {
    color: var(--danger);
    text-decoration: none;
}

/* Footer */
footer {
    background: var(--bg-card);
    padding: 3rem 0;
    text-align: center;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.footer-logo {
    font-size: 1.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
}

/* Footer */
footer {
    background: var(--bg-card);
    padding: 3rem 0;
    text-align: center;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

/* Mobile Responsiveness Improvements */
@media (max-width: 768px) {
    .section-container {
        padding: 0.5rem;
    }

    .calendar-days-header {
        display: none; /* Hide the Sun-Sat header on mobile */
    }

    .calendar-grid {
        grid-template-columns: 1fr; /* Single column list */
        gap: 10px;
    }

    .calendar-day {
        flex-direction: row; /* Horizontal row */
        align-items: center;
        justify-content: space-between;
        min-height: auto;
        padding: 1rem;
        background: rgba(255, 255, 255, 0.03);
        border: 1px solid rgba(255, 255, 255, 0.1);
    }

    .calendar-day.disabled {
        display: none; /* Hide past days and Sundays to keep the list clean */
    }

    .day-number {
        font-size: 1.5rem;
        margin-bottom: 0;
        min-width: 50px;
        color: var(--primary);
    }

    .day-indicators {
        flex: 1;
        display: flex;
        flex-direction: column;
        align-items: flex-end;
        gap: 4px;
    }

    .indicator {
        font-size: 0.7rem;
        padding: 4px 8px;
        margin-bottom: 0;
        width: auto;
        text-align: right;
    }

    .student-name {
        display: inline-block;
        margin-right: 5px;
    }

    .modal-content {
        padding: 1.5rem;
        width: 95%;
        border-radius: 12px;
    }

    .slots-container {
        grid-template-columns: 1fr;
    }

    .booking-layout {
        grid-template-columns: 1fr;
    }
    
    .menu-toggle {
        display: flex;
    }
    
    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--bg-card);
        padding: 2rem;
        gap: 1.5rem;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }

    .nav-links.active {
        display: flex;
    }

    .hero h1 {
        font-size: 2.5rem;
    }
}