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

body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    color: #000;
    background-color: #fff;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.navbar {
    border-bottom: 1px solid #000;
    padding: 20px 0;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand {
    font-size: 24px;
    font-weight: bold;
    text-decoration: none;
    color: #000;
}

.nav-links {
    display: flex;
    gap: 40px;
}

.nav-link {
    text-decoration: none;
    color: #000;
    font-size: 18px;
}

.nav-link:hover, .nav-link.active {
    text-decoration: underline;
}

.main-content {
    flex: 1;
    max-width: 1200px;
    margin: 0 auto;
    padding: 60px 20px;
    width: 100%;
    text-align: center;
}

.footer {
    border-top: 1px solid #000;
    text-align: center;
    padding: 20px;
    margin-top: auto;
}

.btn {
    padding: 12px 24px;
    border: 2px solid #000;
    background: #fff;
    cursor: pointer;
    font-size: 16px;
    text-decoration: none;
    display: inline-block;
    text-align: center;
    margin: 8px;
}

.btn:hover {
    background: #000;
    color: #fff;
}

.btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.btn:disabled:hover {
    background: #fff;
    color: #000;
}

.form-group {
    margin-bottom: 20px;
    text-align: left;
}

.form-label {
    display: block;
    margin-bottom: 8px;
    font-size: 16px;
    font-weight: bold;
}

.form-input {
    width: 100%;
    padding: 12px;
    border: 2px solid #000;
    background: #fff;
    font-size: 16px;
}

.form-input:focus {
    outline: none;
    background: #f0f0f0;
}

.card {
    border: 2px solid #000;
    padding: 40px;
    margin: 20px auto;
    max-width: 600px;
    text-align: center;
}

.week-view {
    border: 2px solid #000;
    margin: 40px auto;
    max-width: 1000px;
}

.week-header {
    display: grid;
    grid-template-columns: 80px repeat(7, 1fr);
    border-bottom: 2px solid #000;
}

.time-column {
    border-right: 1px solid #000;
    font-weight: bold;
    text-align: center;
}

.day-header {
    padding: 12px;
    font-weight: bold;
    text-align: center;
    border-right: 1px solid #000;
}

.day-header:last-child {
    border-right: none;
}

.week-grid {
    display: grid;
    grid-template-columns: 80px repeat(7, 1fr);
}

.time-slot {
    border-bottom: 1px solid #000;
    border-right: 1px solid #000;
    padding: 8px;
    text-align: center;
    cursor: pointer;
    user-select: none;
    min-height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.time-slot:last-child {
    border-right: none;
}

.time-label {
    border-bottom: 1px solid #000;
    border-right: 1px solid #000;
    padding: 8px;
    text-align: center;
    font-size: 12px;
    min-height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.time-slot.selected {
    background: #000;
    color: #fff;
}

.time-slot.available {
    background: #f0f0f0;
}

.time-slot.booked {
    background: #e0e0e0;
    text-decoration: line-through;
    cursor: not-allowed;
}

.calendar-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 2px;
    border: 2px solid #000;
    margin: 40px auto;
    max-width: 800px;
}

.calendar-day {
    border: 1px solid #000;
    padding: 20px;
    text-align: center;
    cursor: pointer;
    min-height: 80px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.calendar-day:hover {
    background: #f0f0f0;
}

.calendar-day.has-slots {
    font-weight: bold;
}

.calendar-day.disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.calendar-day.disabled:hover {
    background: #fff;
}

.day-number {
    font-size: 18px;
    margin-bottom: 4px;
}

.day-info {
    font-size: 12px;
}

.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(255, 255, 255, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal-content {
    border: 2px solid #000;
    padding: 40px;
    background: #fff;
    width: 100%;
    max-width: 500px;
    margin: 20px;
    text-align: center;
}

.modal-buttons {
    margin-top: 20px;
}

.alert {
    padding: 16px;
    border: 2px solid #000;
    margin: 20px 0;
    text-align: center;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin: 40px 0;
}

.stat-card {
    border: 2px solid #000;
    padding: 20px;
    text-align: center;
}

.stat-value {
    font-size: 36px;
    font-weight: bold;
    margin: 8px 0;
}

.stat-label {
    font-size: 14px;
}

.table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
    border: 2px solid #000;
}

.table th,
.table td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid #000;
    border-right: 1px solid #000;
}

.table th:last-child,
.table td:last-child {
    border-right: none;
}

.table th {
    font-weight: bold;
    border-bottom: 2px solid #000;
}

.table tr:last-child td {
    border-bottom: none;
}

.text-center {
    text-align: center;
}

.hidden {
    display: none;
}

.loading {
    text-align: center;
    padding: 60px;
    font-size: 18px;
}

.day-view {
    border: 2px solid #000;
    margin: 40px auto;
    max-width: 600px;
}

.day-view-header {
    padding: 20px;
    font-size: 20px;
    font-weight: bold;
    text-align: center;
    border-bottom: 2px solid #000;
}

.day-slots {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    gap: 1px;
}

.day-slot {
    border: 1px solid #000;
    padding: 16px;
    text-align: center;
    cursor: pointer;
    user-select: none;
}

.day-slot:hover {
    background: #f0f0f0;
}

.day-slot.available {
    font-weight: bold;
}

.day-slot.booked {
    text-decoration: line-through;
    opacity: 0.5;
    cursor: not-allowed;
}

.day-slot.booked:hover {
    background: #fff;
}

@media (max-width: 768px) {
    .week-header,
    .week-grid {
        grid-template-columns: 60px repeat(7, 1fr);
    }
    
    .calendar-grid {
        gap: 1px;
    }
    
    .nav-container {
        padding: 0 16px;
    }
    
    .main-content {
        padding: 40px 16px;
    }
    
    .modal-content {
        margin: 10px;
        padding: 20px;
    }
    
    .nav-links {
        gap: 20px;
    }
    
    .card {
        padding: 20px;
    }
}