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

body {
    font-family: 'Arial', sans-serif;
    background: #f5f5f5;
    min-height: 100vh;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    background: white;
    padding: 20px;
    margin-bottom: 30px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 3px solid #F59E0B;
}

.header-brand {
    display: flex;
    align-items: center;
    gap: 15px;
}

.site-logo {
    width: 40px;
    height: 40px;
    object-fit: contain;
}

h1 {
    color: #F59E0B;
    font-size: 2.5em;
    font-weight: bold;
}

nav {
    display: flex;
    gap: 15px;
}

.nav-btn {
    background: #F59E0B;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    font-weight: 500;
    margin-left: 5px;
}

.nav-btn:hover {
    background: #D97706;
}

.form-container {
    background: white;
    padding: 40px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    max-width: 400px;
    margin: 0 auto;
    border: 1px solid #ddd;
}

.form-container h2 {
    color: #F59E0B;
    margin-bottom: 30px;
    text-align: center;
    font-size: 2em;
}

.form-container input {
    width: 100%;
    padding: 15px;
    margin-bottom: 20px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 16px;
    transition: border-color 0.3s ease;
}

.form-container input:focus {
    outline: none;
    border-color: #4ecdc4;
    box-shadow: 0 0 0 3px rgba(78, 205, 196, 0.2);
}

.form-container button {
    width: 100%;
    background: #F59E0B;
    color: white;
    border: none;
    padding: 15px;
    border-radius: 4px;
    font-size: 16px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    font-weight: 500;
}

.form-container button:hover {
    background: #D97706;
}

.form-container p {
    text-align: center;
    margin-top: 20px;
    color: #666;
}

.form-container a {
    color: #5a6c7d;
    text-decoration: none;
    font-weight: 500;
}

.form-container a:hover {
    text-decoration: underline;
}

.schedule-container {
    background: white;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    border: 1px solid #ddd;
}

.schedule-container h2 {
    color: #F59E0B;
    margin-bottom: 30px;
    text-align: center;
    font-size: 2em;
}

#calendar {
    background: white;
    border-radius: 10px;
    padding: 0;
    min-height: 500px;
    border: 2px solid #e0e0e0;
    overflow: hidden;
}

.week-tabs {
    display: flex;
    background: #f8f9fa;
    border-bottom: 2px solid #e0e0e0;
}

.day-tab {
    flex: 1;
    padding: 15px 20px;
    background: transparent;
    border: none;
    cursor: pointer;
    font-size: 16px;
    font-weight: 500;
    color: #666;
    transition: all 0.3s ease;
    border-bottom: 3px solid transparent;
}

.day-tab:hover {
    background: rgba(90, 108, 125, 0.1);
    color: #5a6c7d;
}

.day-tab.active {
    background: white;
    color: #5a6c7d;
    border-bottom-color: #5a6c7d;
}

.schedule-content {
    padding: 20px;
    max-height: 400px;
    overflow-y: auto;
}

.lesson-block {
    display: flex;
    align-items: center;
    background: #F59E0B;
    color: white;
    padding: 15px;
    border-radius: 4px;
    margin-bottom: 12px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.lesson-block:hover {
    background: #D97706;
}

.lesson-block.completed {
    background: #9E9E9E;
    opacity: 0.8;
}

.lesson-block.completed:hover {
    background: #757575;
}

.lesson-time {
    font-size: 14px;
    font-weight: bold;
    min-width: 60px;
    background: rgba(255, 255, 255, 0.2);
    padding: 5px 10px;
    border-radius: 8px;
    text-align: center;
}

.lesson-details {
    flex: 1;
    margin: 0 15px;
}

.lesson-title {
    font-weight: bold;
    font-size: 16px;
    margin-bottom: 4px;
}

.lesson-location {
    font-size: 14px;
    opacity: 0.9;
}

.lesson-end-time {
    font-size: 12px;
    opacity: 0.8;
    min-width: 50px;
    text-align: right;
}

.no-lessons {
    text-align: center;
    color: #666;
    font-style: italic;
    padding: 40px 20px;
    font-size: 16px;
}

.calendar-event {
    background: #5a6c7d;
    color: white;
    padding: 10px;
    border-radius: 8px;
    margin: 5px 0;
    box-shadow: 0 2px 8px rgba(90, 108, 125, 0.2);
}

.alert {
    padding: 15px;
    margin: 20px 0;
    border-radius: 10px;
    text-align: center;
    font-weight: 500;
}

.alert.success {
    background: rgba(90, 108, 125, 0.1);
    color: #5a6c7d;
    border: 2px solid #5a6c7d;
}

.alert.error {
    background: rgba(220, 53, 69, 0.1);
    color: #dc3545;
    border: 2px solid #dc3545;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.system-message {
    align-self: center;
    background: #ffc107;
    color: #333;
    font-size: 12px;
    padding: 6px 12px;
    border-radius: 4px;
    margin: 10px 0;
}

/* Scrollbar styling */
.chat-messages::-webkit-scrollbar {
    width: 6px;
}

.chat-messages::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 10px;
}

.chat-messages::-webkit-scrollbar-thumb {
    background: #F59E0B;
    border-radius: 10px;
}

.chat-messages::-webkit-scrollbar-thumb:hover {
    background: #D97706;
}

/* Mobile Responsive Styles */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }

    header {
        flex-direction: column;
        gap: 15px;
        padding: 15px;
        text-align: center;
    }

    h1 {
        font-size: 1.8em;
    }

    nav {
        flex-wrap: wrap;
        justify-content: center;
        gap: 8px;
    }

    .nav-btn {
        padding: 8px 12px;
        font-size: 14px;
    }

    .form-container {
        padding: 20px;
        margin: 0 10px;
    }

    .form-container h2 {
        font-size: 1.5em;
    }

    .schedule-container {
        padding: 15px;
    }

    .schedule-container h2 {
        font-size: 1.5em;
    }

    .week-tabs {
        flex-wrap: wrap;
    }

    .day-tab {
        flex: 1;
        min-width: 80px;
        padding: 10px 8px;
        font-size: 14px;
    }

    .lesson-block {
        flex-direction: column;
        align-items: flex-start;
        gap: 8px;
        padding: 12px;
    }

    .lesson-time {
        min-width: auto;
        font-size: 12px;
    }

    .lesson-details {
        margin: 0;
        width: 100%;
    }

    .lesson-title {
        font-size: 14px;
    }

    .lesson-location {
        font-size: 12px;
    }

    .lesson-end-time {
        min-width: auto;
        text-align: left;
        font-size: 11px;
    }

    .schedule-content {
        padding: 10px;
        max-height: none;
    }

    #calendar {
        min-height: 400px;
    }
}