:root {
    --primary-blue: #007bff;
    --background: #f4f6f9;
    --card-bg: #ffffff;
    --text-primary: #333333;
    --text-secondary: #666666;
    --border: #e0e0e0;
    --free: #28a745;
    --busy: #6c757d;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: 'Roboto', sans-serif; background: var(--background); color: var(--text-primary); }

.header { 
    background: var(--primary-blue); 
    color: white; 
    padding: 20px; 
    text-align: center; 
    font-size: 1.5rem; 
    font-weight: 500;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.container { 
    max-width: 600px; 
    margin: 0 auto; 
    padding: 20px; 
}

.date-selector { 
    display: flex; 
    align-items: center; 
    justify-content: space-between; 
    margin-bottom: 20px; 
    background: white; 
    padding: 15px; 
    border-radius: 8px; 
    box-shadow: 0 2px 4px rgba(0,0,0,0.05); 
}

.nav-arrow { 
    cursor: pointer; 
    color: var(--primary-blue); 
    font-size: 1.2rem; 
    padding: 10px;
}

.date-text {
    font-size: 1.1rem;
    font-weight: 500;
}

.slots-container { 
    display: flex; 
    flex-direction: column; 
    gap: 10px; 
    margin-bottom: 30px;
}

.slot { 
    display: flex; 
    align-items: center; 
    justify-content: space-between; 
    background: white; 
    padding: 15px 20px; 
    border-radius: 8px; 
    box-shadow: 0 1px 3px rgba(0,0,0,0.05); 
    transition: background 0.2s, transform 0.1s; 
}

.slot.free { 
    cursor: pointer; 
    border-left: 5px solid var(--free); 
}
.slot.free:active {
    transform: scale(0.98);
}
.slot.busy { 
    border-left: 5px solid var(--busy); 
    opacity: 0.6; 
    cursor: not-allowed; 
}

.slot-time { 
    font-weight: bold; 
    font-size: 1.1rem; 
}

.slot-status { 
    font-size: 0.9rem; 
    padding: 4px 8px; 
    border-radius: 4px; 
    font-weight: 500;
}
.slot.free .slot-status { background: #e6f4ea; color: var(--free); }
.slot.busy .slot-status { background: #e9ecef; color: var(--busy); }

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
    align-items: center;
    justify-content: center;
}

.modal-content {
    background-color: #fff;
    padding: 20px;
    border-radius: 8px;
    width: 90%;
    max-width: 400px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.close-modal {
    color: #aaa;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}
.close-modal:hover { color: #333; }

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    color: var(--text-secondary);
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border);
    border-radius: 4px;
    font-family: inherit;
    font-size: 1rem;
}

.btn {
    padding: 10px 15px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-weight: 500;
    font-size: 1rem;
    transition: opacity 0.2s;
}
.btn:hover { opacity: 0.9; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-primary { background-color: var(--primary-blue); color: white; }
.btn-secondary { background-color: #e0e0e0; color: #333; }