/* Minimal and Elegant Design System */
:root {
    --primary-color: #1a1a1a;
    --accent-color: #2563eb;
    --text-primary: #1a1a1a;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --border-color: #e5e7eb;
    --border-light: #f3f4f6;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-secondary);
    font-size: 14px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Modal Styles */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(8px);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal-content {
    background: var(--bg-primary);
    padding: 48px;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    max-width: 420px;
    width: 90%;
    border: 1px solid var(--border-light);
}

.login-header {
    text-align: center;
    margin-bottom: 40px;
}

.login-header h2 {
    color: var(--text-primary);
    margin-bottom: 8px;
    font-size: 24px;
    font-weight: 600;
    letter-spacing: -0.025em;
}

.login-header p {
    color: var(--text-secondary);
    font-size: 15px;
    font-weight: 400;
}

.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-primary);
    font-weight: 500;
    font-size: 14px;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 14px;
    transition: all 0.2s ease;
    background: var(--bg-primary);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.08);
}

.login-btn {
    width: 100%;
    background: var(--text-primary);
    color: var(--bg-primary);
    border: none;
    padding: 12px 24px;
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.login-btn:hover {
    background: #000;
    transform: translateY(-1px);
}

/* Login Toggle */
.login-toggle {
    display: flex;
    background: var(--bg-tertiary);
    border-radius: var(--radius-md);
    padding: 4px;
    margin-bottom: 28px;
    gap: 4px;
}

.toggle-btn {
    flex: 1;
    padding: 10px 16px;
    border: none;
    background: transparent;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s ease;
}

.toggle-btn.active {
    background: var(--bg-primary);
    color: var(--text-primary);
    box-shadow: var(--shadow-sm);
}

.toggle-btn:hover:not(.active) {
    color: var(--text-primary);
}

.form-subtitle {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 24px;
    line-height: 1.5;
}

/* CTA Card (new signups) */
.folder-card.cta-card {
    background: linear-gradient(135deg, #f0f4ff, #f5f0ff);
    border: 1px solid #e0e7ff;
}

.folder-card.cta-card i:first-child {
    font-size: 40px;
    color: var(--accent-color);
    margin-bottom: 20px;
}

.cta-btn {
    background: var(--accent-color) !important;
}

.cta-btn:hover {
    background: #1d4ed8 !important;
}

.hidden {
    display: none !important;
}

/* Header */
header {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

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

header h1 {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    letter-spacing: -0.025em;
}

header h1 i {
    margin-right: 8px;
    color: var(--accent-color);
}

.user-info {
    display: flex;
    align-items: center;
    gap: 16px;
}

#welcomeMessage {
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 14px;
}

.logout-btn {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 13px;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 6px;
}

.logout-btn:hover {
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.main-nav {
    display: flex;
    gap: 1px;
    background: var(--border-color);
    margin: 0 -24px;
    padding: 0 24px;
}

.nav-btn {
    background: transparent;
    color: var(--text-secondary);
    border: none;
    padding: 16px 24px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 8px;
    border-radius: var(--radius-md) var(--radius-md) 0 0;
    position: relative;
}

.nav-btn:hover {
    color: var(--text-primary);
    background: var(--bg-secondary);
}

.nav-btn.active {
    color: var(--text-primary);
    background: var(--bg-primary);
}

.nav-btn.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--bg-primary);
}

/* Main Content */
main {
    padding: 48px 0;
    min-height: calc(100vh - 200px);
}

.content-section {
    display: none;
    animation: fadeIn 0.3s ease;
}

.content-section.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Cards */
.welcome-card {
    background: var(--bg-primary);
    padding: 40px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    margin-bottom: 32px;
}

.welcome-card h3 {
    color: var(--text-primary);
    margin-bottom: 12px;
    font-size: 24px;
    font-weight: 600;
    letter-spacing: -0.025em;
}

.welcome-card p {
    color: var(--text-secondary);
    margin-bottom: 32px;
    font-size: 16px;
    line-height: 1.7;
}

.resource-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.resource-card {
    background: var(--bg-primary);
    padding: 32px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    transition: all 0.2s ease;
    text-align: center;
}

.resource-card:hover {
    border-color: var(--border-color);
    transform: translateY(-2px);
}

.resource-card i {
    font-size: 32px;
    color: var(--accent-color);
    margin-bottom: 16px;
}

.resource-card h4 {
    margin-bottom: 8px;
    color: var(--text-primary);
    font-size: 16px;
    font-weight: 600;
}

.resource-card p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.5;
}

/* Tabs */
.tab-nav {
    display: flex;
    gap: 1px;
    background: var(--border-color);
    margin-bottom: 32px;
    border-radius: var(--radius-md);
    overflow: hidden;
}

.tab-btn {
    background: transparent;
    border: none;
    padding: 16px 24px;
    cursor: pointer;
    font-size: 14px;
    color: var(--text-secondary);
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 500;
    flex: 1;
    justify-content: center;
}

.tab-btn:hover {
    color: var(--text-primary);
    background: var(--bg-secondary);
}

.tab-btn.active {
    color: var(--text-primary);
    background: var(--bg-primary);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.tab-content {
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: 40px;
    border: 1px solid var(--border-light);
}

.tab-pane {
    display: none;
    animation: fadeIn 0.3s ease;
}

.tab-pane.active {
    display: block;
}

/* Resource Sections */
.resource-section {
    margin-bottom: 40px;
}

.resource-section:last-child {
    margin-bottom: 0;
}

.resource-section h3 {
    color: var(--text-primary);
    margin-bottom: 20px;
    font-size: 18px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 8px;
}

.link-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 16px;
}

.link-card {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 24px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    text-decoration: none;
    color: var(--text-primary);
    transition: all 0.2s ease;
}

.link-card:hover {
    border-color: var(--border-color);
    transform: translateY(-1px);
    color: var(--accent-color);
}

.link-card i {
    font-size: 24px;
    color: var(--accent-color);
}

.link-card span {
    font-size: 14px;
    font-weight: 500;
}

/* Personal Folder */
.section-description {
    color: var(--text-secondary);
    margin-bottom: 24px;
    font-size: 15px;
}

.personal-folder {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

.personal-folder .folder-card {
    background: var(--bg-secondary);
    padding: 40px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    text-align: center;
    transition: all 0.2s ease;
}

.personal-folder .folder-card:hover {
    border-color: var(--border-color);
    transform: translateY(-2px);
}

.personal-folder .folder-card i {
    font-size: 40px;
    color: var(--accent-color);
    margin-bottom: 20px;
}

.personal-folder .folder-card h4 {
    color: var(--text-primary);
    margin-bottom: 12px;
    font-size: 20px;
    font-weight: 600;
}

.personal-folder .folder-card p {
    color: var(--text-secondary);
    margin-bottom: 24px;
    font-size: 15px;
    line-height: 1.6;
}

.personal-folder .access-btn {
    background: var(--text-primary);
    color: var(--bg-primary);
    border: none;
    padding: 12px 24px;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.personal-folder .access-btn:hover {
    background: #000;
    transform: translateY(-1px);
}

.drive-embed {
    margin-top: 24px;
}

.drive-embed iframe {
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
}

/* Media Cards (Movies/TV Shows) */
.media-subtitle {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 28px;
    font-style: italic;
}

.media-category {
    margin-bottom: 32px;
}

.media-category:last-child {
    margin-bottom: 0;
}

.category-label {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 16px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border-light);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.media-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 20px;
}

.media-card {
    text-decoration: none;
    color: var(--text-primary);
    border-radius: var(--radius-md);
    overflow: hidden;
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    transition: all 0.25s ease;
}

.media-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: var(--border-color);
}

.media-poster {
    position: relative;
    aspect-ratio: 2/3;
    background: var(--bg-tertiary);
    overflow: hidden;
}

.media-poster img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.media-poster.no-poster {
    display: flex;
    align-items: center;
    justify-content: center;
}

.media-poster.no-poster::after {
    content: '\f008';
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
    font-size: 32px;
    color: var(--text-light);
}

.media-type-badge {
    position: absolute;
    top: 8px;
    right: 8px;
    background: rgba(0, 0, 0, 0.7);
    color: #fff;
    font-size: 10px;
    font-weight: 600;
    padding: 3px 8px;
    border-radius: 4px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.media-info {
    padding: 12px;
}

.media-info h5 {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 4px;
    line-height: 1.3;
}

.media-meta {
    font-size: 12px;
    color: var(--text-secondary);
    display: block;
}

.media-genre {
    font-size: 11px;
    color: var(--accent-color);
    display: block;
    margin-top: 4px;
    font-weight: 500;
}

/* Coming Soon (greyed-out resources) */
.coming-soon-section {
    position: relative;
}

.coming-soon-overlay {
    text-align: center;
    padding: 40px 24px;
    margin-bottom: 24px;
}

.coming-soon-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: 10px 24px;
    border-radius: 50px;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 12px;
    border: 1px solid var(--border-color);
}

.coming-soon-badge i {
    color: var(--accent-color);
}

.coming-soon-overlay p {
    color: var(--text-light);
    font-size: 15px;
}

.coming-soon-content {
    opacity: 0.35;
    pointer-events: none;
    filter: grayscale(1);
}

.link-card.disabled {
    cursor: default;
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 24px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    color: var(--text-primary);
}

.link-card.disabled i {
    font-size: 24px;
    color: var(--accent-color);
}

.link-card.disabled span {
    font-size: 14px;
    font-weight: 500;
}

/* AI Companion */
.ai-companion-section {
    max-width: 100%;
}

.ai-intro {
    text-align: center;
    margin-bottom: 32px;
    padding: 0 24px;
}

.ai-intro-icon {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--accent-color), #7c3aed);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
}

.ai-intro-icon i {
    font-size: 28px;
    color: #fff;
}

.ai-intro h3 {
    font-size: 22px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 12px;
    letter-spacing: -0.025em;
}

.ai-intro-text {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.7;
    max-width: 600px;
    margin: 0 auto;
}

.ai-chat-container {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border-light);
}

.ai-chat-messages {
    height: 400px;
    overflow-y: auto;
    padding: 24px;
    background: var(--bg-primary);
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.ai-message {
    display: flex;
    gap: 12px;
    align-items: flex-start;
    max-width: 85%;
    animation: fadeIn 0.3s ease;
}

.ai-message.ai-bot {
    align-self: flex-start;
}

.ai-message.ai-user {
    align-self: flex-end;
}

.ai-avatar {
    width: 36px;
    height: 36px;
    min-width: 36px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--accent-color), #7c3aed);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 14px;
}

.ai-avatar.user-avatar {
    background: var(--text-primary);
}

.ai-bubble {
    background: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    padding: 14px 18px;
    font-size: 14px;
    line-height: 1.6;
    color: var(--text-primary);
}

.ai-bubble p {
    margin: 0;
}

.ai-bubble em {
    color: var(--accent-color);
    font-style: italic;
}

.ai-message.ai-user .ai-bubble {
    background: var(--text-primary);
    color: #fff;
    border-color: var(--text-primary);
}

/* Typing indicator */
.typing-indicator {
    display: flex;
    gap: 4px;
    padding: 16px 20px;
    align-items: center;
}

.typing-indicator span {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--text-light);
    animation: typing 1.4s infinite;
}

.typing-indicator span:nth-child(2) {
    animation-delay: 0.2s;
}

.typing-indicator span:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes typing {
    0%, 60%, 100% { transform: translateY(0); opacity: 0.4; }
    30% { transform: translateY(-6px); opacity: 1; }
}

.ai-chat-input-container {
    display: flex;
    padding: 16px 24px;
    background: var(--bg-primary);
    border-top: 1px solid var(--border-light);
    gap: 12px;
}

#aiMessageInput {
    flex: 1;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 14px;
    outline: none;
    background: var(--bg-secondary);
}

#aiMessageInput:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.08);
}

#aiSendMessage {
    background: linear-gradient(135deg, var(--accent-color), #7c3aed);
    color: #fff;
    border: none;
    padding: 12px 16px;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

#aiSendMessage:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

/* Record Button */
.record-btn {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
    width: 44px;
    height: 44px;
    min-width: 44px;
    border-radius: 50%;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
}

.record-btn:hover {
    color: var(--accent-color);
    border-color: var(--accent-color);
}

.record-btn.recording {
    background: #ef4444;
    color: #fff;
    border-color: #ef4444;
    animation: pulse-record 1s infinite;
}

@keyframes pulse-record {
    0%, 100% { box-shadow: 0 0 0 0 rgba(239, 68, 68, 0.4); }
    50% { box-shadow: 0 0 0 8px rgba(239, 68, 68, 0); }
}

/* Voice Messages */
.voice-bubble {
    padding: 12px 16px !important;
}

.voice-msg-label {
    font-size: 12px;
    color: var(--text-light);
    margin-bottom: 8px;
    display: flex;
    align-items: center;
    gap: 6px;
}

.voice-bubble audio {
    width: 100%;
    height: 36px;
    border-radius: 4px;
}

.ai-message.ai-user .voice-msg-label {
    color: rgba(255,255,255,0.7);
}

/* Signup Success Card */
.success-card {
    text-align: center;
    padding: 8px 0;
}

.success-icon {
    font-size: 48px;
    color: #059669;
    margin-bottom: 16px;
}

.success-card h3 {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.success-card p {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 16px;
    line-height: 1.5;
}

.access-code-display {
    background: var(--bg-tertiary);
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-md);
    padding: 20px;
    margin: 20px 0;
    text-align: center;
}

.code-label {
    display: block;
    font-size: 12px;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 8px;
}

.code-value {
    display: block;
    font-size: 28px;
    font-weight: 700;
    color: var(--accent-color);
    letter-spacing: 0.1em;
    font-family: 'Courier New', monospace;
}

.code-hint {
    font-size: 13px !important;
    color: var(--text-light) !important;
    margin-bottom: 20px !important;
}

/* Community Chat */
.community-section h3 {
    color: var(--text-primary);
    margin-bottom: 20px;
    font-size: 18px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 8px;
}

.chat-container {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border-light);
}

.chat-messages {
    height: 400px;
    overflow-y: auto;
    padding: 24px;
    background: var(--bg-primary);
}

.message {
    margin-bottom: 20px;
    padding: 20px;
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    border-left: 3px solid var(--accent-color);
}

.message:last-child {
    margin-bottom: 0;
}

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

.message-header strong {
    color: var(--text-primary);
    font-size: 14px;
    font-weight: 600;
}

.message-time {
    font-size: 12px;
    color: var(--text-light);
}

.message-content {
    color: var(--text-secondary);
    line-height: 1.6;
    font-size: 14px;
}

.chat-input-container {
    display: flex;
    padding: 16px 24px;
    background: var(--bg-primary);
    border-top: 1px solid var(--border-light);
    gap: 12px;
}

#messageInput {
    flex: 1;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 14px;
    outline: none;
    background: var(--bg-secondary);
}

#messageInput:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.08);
}

#sendMessage {
    background: var(--text-primary);
    color: var(--bg-primary);
    border: none;
    padding: 12px 16px;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

#sendMessage:hover {
    background: #000;
}

/* Footer */
footer {
    background: var(--bg-primary);
    text-align: center;
    padding: 32px 0;
    margin-top: 48px;
    border-top: 1px solid var(--border-color);
}

footer p {
    color: var(--text-light);
    font-size: 13px;
}

/* Floating Book Lesson Button */
.floating-book-btn {
    position: fixed;
    bottom: 24px;
    right: 24px;
    background: var(--accent-color);
    color: var(--bg-primary);
    border: none;
    border-radius: 50px;
    padding: 16px 24px;
    box-shadow: var(--shadow-lg);
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 14px;
    font-weight: 600;
    z-index: 999;
    min-width: 200px;
    justify-content: center;
    text-decoration: none;
}

.floating-book-btn:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.15);
}

.floating-book-btn i {
    font-size: 18px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }
    
    .modal-content {
        padding: 32px 24px;
        margin: 16px;
    }
    
    .header-top {
        flex-direction: column;
        gap: 16px;
        align-items: flex-start;
    }
    
    .main-nav {
        margin: 0 -16px;
        padding: 0 16px;
    }
    
    .nav-btn {
        padding: 12px 16px;
        font-size: 13px;
    }
    
    .tab-nav {
        flex-direction: column;
    }
    
    .tab-btn {
        border-radius: 0;
        justify-content: flex-start;
    }
    
    .welcome-card,
    .tab-content {
        padding: 24px;
    }
    
    .resource-grid {
        grid-template-columns: 1fr;
    }
    
    .link-grid {
        grid-template-columns: 1fr;
    }
    
    .chat-messages {
        height: 300px;
        padding: 16px;
    }
    
    .chat-input-container {
        padding: 12px 16px;
    }
    
    /* Floating button responsive */
    .floating-book-btn {
        bottom: 16px;
        right: 16px;
        min-width: 160px;
        padding: 12px 20px;
        font-size: 13px;
    }
    
    .floating-book-btn span {
        display: none;
    }
    
    .floating-book-btn {
        border-radius: 50%;
        width: 56px;
        height: 56px;
        min-width: auto;
    }
}