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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    overflow: hidden;
}

/* Header */
.header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 40px 30px;
    text-align: center;
}

.title {
    font-size: 3em;
    margin-bottom: 20px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
    font-weight: 700;
}

.nav {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 20px;
}

.nav-btn {
    padding: 12px 30px;
    background: rgba(255, 255, 255, 0.2);
    border: 2px solid white;
    color: white;
    border-radius: 25px;
    cursor: pointer;
    font-size: 1em;
    font-weight: 600;
    transition: all 0.3s ease;
}

.nav-btn:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
}

.nav-btn.active {
    background: white;
    color: #667eea;
}

/* Login Section */
.login-section {
    padding: 20px 30px;
    text-align: right;
    background: #f8f9fa;
    border-bottom: 1px solid #e0e0e0;
    display: flex;
    justify-content: flex-end;
    align-items: center;
    gap: 10px;
}

/* Profile Section */
.profile-section {
    display: flex;
    align-items: center;
}

.profile-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 25px;
    cursor: pointer;
    font-size: 1em;
    font-weight: 600;
    transition: all 0.3s ease;
}

.profile-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.profile-icon {
    font-size: 1.2em;
}

.profile-info {
    margin-top: 20px;
}

.profile-stats {
    margin: 20px 0;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 8px;
}

.profile-stats p {
    margin: 5px 0;
    color: #555;
}

.profile-stats strong {
    color: #667eea;
}

.form-group small {
    display: block;
    margin-top: 5px;
    color: #666;
    font-size: 0.85em;
}

/* 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);
    backdrop-filter: blur(5px);
}

.modal-content {
    background-color: white;
    margin: 10% auto;
    padding: 30px;
    border-radius: 15px;
    width: 90%;
    max-width: 400px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
    position: relative;
}

.close,
.close-profile {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    position: absolute;
    right: 20px;
    top: 15px;
}

.close:hover,
.close-profile:hover {
    color: #667eea;
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #555;
}

.form-group input {
    width: 100%;
    padding: 12px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1em;
    transition: border-color 0.3s;
}

.form-group input:focus {
    outline: none;
    border-color: #667eea;
}

.user-info {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid #e0e0e0;
}

/* Buttons */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1em;
    font-weight: 600;
    transition: all 0.3s ease;
    margin: 5px;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: #6c757d;
    color: white;
}

.btn-secondary:hover {
    background: #5a6268;
    transform: translateY(-2px);
}

/* Sections */
.section {
    display: none;
    padding: 30px;
}

.section.active {
    display: block;
}

.section h2 {
    margin-bottom: 25px;
    color: #667eea;
    font-size: 2em;
}

/* Search Bar */
.search-bar {
    margin-bottom: 25px;
}

.search-bar input {
    width: 100%;
    padding: 15px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 1em;
    transition: border-color 0.3s;
}

.search-bar input:focus {
    outline: none;
    border-color: #667eea;
}

/* Add Forms */
.add-teacher-form,
.add-product-form {
    background: #f8f9fa;
    padding: 20px;
    border-radius: 10px;
    margin-bottom: 30px;
}

.add-teacher-form h3,
.add-product-form h3 {
    margin-bottom: 15px;
    color: #667eea;
}

.add-teacher-form form,
.add-product-form form {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.add-teacher-form .form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.add-teacher-form .form-group label {
    font-weight: 600;
    color: #555;
    font-size: 0.95em;
}

.add-teacher-form input,
.add-teacher-form select,
.add-product-form input,
.add-product-form textarea {
    padding: 12px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1em;
    font-family: inherit;
}

.add-teacher-form select {
    width: 100%;
    background-color: white;
    cursor: pointer;
    margin-top: 8px;
}

.add-teacher-form select:focus {
    outline: none;
    border-color: #667eea;
}

.add-teacher-form #teacherSearchInput {
    margin-bottom: 8px;
}

.add-product-form textarea {
    min-height: 100px;
    resize: vertical;
}

/* Teachers List */
.teachers-list {
    display: grid;
    gap: 20px;
}

.teacher-card {
    background: #f8f9fa;
    padding: 25px;
    border-radius: 12px;
    border-left: 4px solid #667eea;
    transition: transform 0.3s, box-shadow 0.3s;
}

.teacher-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.teacher-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.teacher-name {
    font-size: 1.5em;
    font-weight: 700;
    color: #333;
}

.teacher-subject {
    color: #667eea;
    font-weight: 600;
    font-size: 1.1em;
}

.teacher-rating {
    display: flex;
    align-items: center;
    gap: 10px;
    margin: 15px 0;
}

.stars {
    display: flex;
    gap: 5px;
}

.star {
    font-size: 1.5em;
    color: #ddd;
    cursor: pointer;
    transition: color 0.2s;
}

.star.active {
    color: #ffc107;
}

.rating-value {
    font-weight: 600;
    color: #667eea;
}

.rating-count {
    color: #666;
    font-size: 0.9em;
}

/* Admin Controls */
.admin-controls {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    margin-bottom: 15px;
    padding-bottom: 15px;
    border-bottom: 2px solid #e0e0e0;
}

.btn-delete-teacher {
    padding: 10px 20px;
    background: #dc3545;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.95em;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 2px 5px rgba(220, 53, 69, 0.3);
}

.btn-delete-teacher:hover {
    background: #c82333;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(220, 53, 69, 0.4);
}

.ratings-list {
    margin-top: 20px;
    padding: 15px;
    background: #fff;
    border-radius: 8px;
    border: 1px solid #e0e0e0;
}

.ratings-list strong {
    display: block;
    margin-bottom: 10px;
    color: #667eea;
}

.rating-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 0;
    border-bottom: 1px solid #f0f0f0;
}

.rating-item:last-child {
    border-bottom: none;
}

.btn-delete-rating {
    padding: 4px 8px;
    background: #dc3545;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.8em;
    transition: all 0.3s ease;
}

.btn-delete-rating:hover {
    background: #c82333;
    transform: scale(1.1);
}

/* Products Grid */
.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 25px;
}

.product-card {
    background: white;
    border: 2px solid #e0e0e0;
    border-radius: 12px;
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

.product-image {
    width: 100%;
    height: 200px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3em;
}

.product-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.product-info {
    padding: 20px;
}

.product-name {
    font-size: 1.3em;
    font-weight: 700;
    margin-bottom: 10px;
    color: #333;
}

.product-description {
    color: #666;
    margin-bottom: 15px;
    line-height: 1.5;
}

.product-price {
    font-size: 1.5em;
    font-weight: 700;
    color: #667eea;
    margin-bottom: 15px;
}

.product-seller {
    color: #999;
    font-size: 0.9em;
    margin-bottom: 10px;
}

/* Responsive */
@media (max-width: 768px) {
    .title {
        font-size: 2em;
    }

    .nav {
        flex-direction: column;
    }

    .nav-btn {
        width: 100%;
    }

    .products-grid {
        grid-template-columns: 1fr;
    }
}