:root {
    --tg-color-scheme: var(--tg-color-scheme, light);
    --tg-bg-color: var(--tg-theme-bg-color, #f0f2f5);
    --tg-text-color: var(--tg-theme-text-color, #1c1e21);
    --tg-hint-color: var(--tg-theme-hint-color, #65676b);
    --tg-link-color: var(--tg-theme-link-color, #216fdb);
    --tg-button-color: var(--tg-theme-button-color, #216fdb);
    --tg-button-text-color: var(--tg-theme-button-text-color, #ffffff);
    --tg-secondary-bg-color: var(--tg-theme-secondary-bg-color, #ffffff);
    --border-radius: 12px;
    --box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1), 0 8px 16px rgba(0, 0, 0, 0.1);
    --transition: all 0.2s ease;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background: var(--tg-bg-color);
    color: var(--tg-text-color);
    padding: 16px;
    line-height: 1.5;
    min-height: 100vh;
}

button {
    background: linear-gradient(145deg, var(--tg-button-color), #1a5bbf);
    color: var(--tg-button-text-color);
    border: none;
    border-radius: var(--border-radius);
    padding: 12px 20px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    width: 100%;
    margin: 8px 0;
    transition: var(--transition);
    box-shadow: var(--box-shadow);
    position: relative;
    overflow: hidden;
}

button::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 5px;
    height: 5px;
    background: rgba(255, 255, 255, 0.5);
    opacity: 0;
    border-radius: 100%;
    transform: scale(1, 1) translate(-50%);
    transform-origin: 50% 50%;
}

button:focus:not(:active)::after {
    animation: ripple 1s ease-out;
}

@keyframes ripple {
    0% {
        transform: scale(0, 0);
        opacity: 0.5;
    }
    20% {
        transform: scale(25, 25);
        opacity: 0.3;
    }
    100% {
        opacity: 0;
        transform: scale(40, 40);
    }
}

button:active {
    transform: scale(0.98);
    opacity: 0.9;
}

button.back-button {
    background: transparent;
    color: var(--tg-link-color);
    box-shadow: none;
    width: auto;
    padding: 8px 12px;
    font-weight: 500;
}

button.back-button::after {
    display: none;
}

button.tab {
    background: transparent;
    color: var(--tg-text-color);
    border: 1px solid var(--tg-hint-color);
    border-radius: 30px;
    padding: 8px 12px;
    font-size: 14px;
    font-weight: 500;
    margin: 4px;
    flex: 1;
    box-shadow: none;
    transition: var(--transition);
}

button.tab.active {
    background: linear-gradient(145deg, var(--tg-button-color), #1a5bbf);
    color: var(--tg-button-text-color);
    border-color: var(--tg-button-color);
    box-shadow: var(--box-shadow);
}

input, textarea, select {
    width: 100%;
    padding: 12px;
    margin: 8px 0;
    border: 1px solid var(--tg-hint-color);
    border-radius: var(--border-radius);
    background: var(--tg-secondary-bg-color);
    color: var(--tg-text-color);
    font-size: 16px;
    transition: var(--transition);
}

input:focus, textarea:focus, select:focus {
    outline: none;
    border-color: var(--tg-button-color);
    box-shadow: 0 0 0 3px rgba(33, 111, 219, 0.2);
}

.card {
    background: var(--tg-secondary-bg-color);
    border-radius: var(--border-radius);
    padding: 16px;
    margin: 12px 0;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
    border: 1px solid rgba(0, 0, 0, 0.05);
    animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
}

.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding: 8px 0;
}

.logo-img {
    max-width: 150px;
    height: auto;
    display: block;
    margin-bottom: 10px;
}

h1 {
    font-size: 28px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--tg-button-color) 0%, #6610f2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin: 0;
}

h2 {
    font-size: 22px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--tg-text-color);
}

h3 {
    font-size: 18px;
    font-weight: 600;
    margin: 16px 0 8px;
    color: var(--tg-text-color);
}

.tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 20px;
}

.feed .card {
    cursor: pointer;
    border-left: 4px solid var(--tg-button-color);
}

.messages .card {
    border-left: 4px solid var(--tg-link-color);
}

.communities-list .card {
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
}

.books .card {
    display: flex;
    flex-direction: column;
}

.book-cover {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 12px;
}

.meetings .card {
    border-left: 4px solid #28a745;
}

.members-list {
    list-style: none;
    padding: 0;
}

.members-list li {
    padding: 12px;
    border-bottom: 1px solid var(--tg-hint-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.members-list li:last-child {
    border-bottom: none;
}

.role {
    background: var(--tg-button-color);
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
}

.modal {
    background: var(--tg-secondary-bg-color);
    border-radius: 16px;
    padding: 24px;
    margin: 20px 0;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(0, 0, 0, 0.1);
}

.file-input {
    display: none;
}

.file-label {
    display: inline-block;
    background: linear-gradient(145deg, var(--tg-button-color), #1a5bbf);
    color: white;
    padding: 10px 16px;
    border-radius: var(--border-radius);
    cursor: pointer;
    margin: 8px 0;
    font-size: 14px;
    transition: var(--transition);
}

.file-label:hover {
    opacity: 0.9;
}

.preview-image {
    max-width: 100%;
    max-height: 200px;
    margin: 10px 0;
    border-radius: 8px;
    object-fit: cover;
}

.profile-info {
    background: var(--tg-secondary-bg-color);
    border-radius: var(--border-radius);
    padding: 24px;
    margin: 16px 0;
    text-align: center;
    box-shadow: var(--box-shadow);
    border: 1px solid rgba(0, 0, 0, 0.05);
}

.avatar {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--tg-button-color), #6610f2);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 36px;
    font-weight: bold;
    margin: 0 auto 16px;
    box-shadow: var(--box-shadow);
    border: 3px solid white;
}

.profile-info p {
    margin: 12px 0;
    font-size: 18px;
}

.error-message {
    background: #f8d7da;
    color: #721c24;
    padding: 16px;
    border-radius: var(--border-radius);
    margin: 20px 0;
    text-align: center;
    border: 1px solid #f5c6cb;
}

.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 200px;
    font-size: 18px;
    color: var(--tg-hint-color);
}

.loading::after {
    content: '';
    width: 24px;
    height: 24px;
    border: 2px solid var(--tg-hint-color);
    border-top-color: var(--tg-button-color);
    border-radius: 50%;
    margin-left: 12px;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

@media (max-width: 480px) {
    body {
        padding: 12px;
    }
    h1 {
        font-size: 24px;
    }
    .tabs {
        flex-direction: column;
    }
    button.tab {
        margin: 2px 0;
    }
}