:root {
    --primary-color: #0056b3;
    --accent-color: #ffab00;
    --bg-color: #f4f4f9;
    --card-bg: #ffffff;
    --text-color: #333;
    --nav-height: 60px;
}

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

/* Utility */
.hidden {
    display: none !important;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    padding-top: var(--nav-height);
}

.app-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--nav-height);
    background-color: var(--primary-color);
    color: white;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 1rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
    z-index: 1000;
}

.app-header h1 {
    font-size: 1.2rem;
    margin-right: 15px;
}

.main-nav {
    display: flex;
    gap: 5px;
    flex: 1;
}

.user-controls {
    display: flex;
    align-items: center;
    gap: 5px;
}

#user-display {
    display: flex;
    align-items: center;
    gap: 5px;
    font-size: 0.9rem;
}
#username-span {
    max-width: 80px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.icon-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 5px;
}

.nav-btn {
    background: none;
    border: none;
    color: rgba(255, 255, 255, 0.7);
    font-size: 1rem;
    cursor: pointer;
    padding: 5px 10px;
    border-radius: 4px;
    transition: all 0.2s;
}

.nav-btn.active {
    color: white;
    background-color: rgba(255, 255, 255, 0.2);
    font-weight: bold;
}

/* Day Filter Bar */
.day-filter-bar {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    width: 100%;
    background-color: #fff;
    display: flex;
    justify-content: center;
    gap: 6px;
    padding: 8px 1rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    z-index: 950;
    flex-wrap: nowrap;
}

.day-btn {
    background: #e8e8e8;
    border: none;
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.2s;
    color: var(--text-color);
    white-space: nowrap;
    flex-shrink: 0;
}

.day-btn:hover {
    background: #d0d0d0;
}

.day-btn.active {
    background-color: var(--primary-color);
    color: white;
    font-weight: 600;
}

/* Time Filter Bar */
.time-filter-bar {
    position: fixed;
    top: calc(var(--nav-height) + 42px);
    left: 0;
    width: 100%;
    background-color: #f9f9f9;
    display: flex;
    justify-content: center;
    gap: 5px;
    padding: 6px 1rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.08);
    z-index: 940;
    flex-wrap: wrap;
}

.time-btn {
    background: #e0e0e0;
    border: none;
    padding: 4px 10px;
    border-radius: 14px;
    font-size: 0.78rem;
    cursor: pointer;
    transition: all 0.2s;
    color: var(--text-color);
    white-space: nowrap;
}

.time-btn:hover {
    background: #d0d0d0;
}

.time-btn.active {
    background-color: var(--accent-color);
    color: #333;
    font-weight: 600;
}

.content {
    padding: 1rem;
    max-width: 800px;
    margin: 0 auto;
    padding-top: 60px;
}

.content.has-time-bar {
    padding-top: 96px;
}

/* Day Sections */
.day-section {
    margin-bottom: 2rem;
}

.day-header {
    position: sticky;
    top: var(--nav-height);
    background-color: var(--bg-color);
    padding: 10px 0;
    font-size: 1.1rem;
    font-weight: bold;
    color: #666;
    border-bottom: 2px solid #ddd;
    z-index: 900;
}

/* Session Cards */
.session-card {
    background: var(--card-bg);
    border-radius: 8px;
    padding: 1rem;
    margin-bottom: 1rem;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    position: relative;
    border-left: 4px solid transparent;
}

.session-card[data-type="Workshop"] { border-left-color: #9c27b0; }
.session-card[data-type="Vortragssession"] { border-left-color: #2196f3; }
.session-card[data-type="Keynote"] { border-left-color: #ff9800; }
.session-card[data-type="Panel"] { border-left-color: #4caf50; }
.session-card[data-type="Poster Session"] { border-left-color: #e91e63; }
.session-card[data-type="Poster Slam"] { border-left-color: #f06292; }
.session-card[data-type="Doctoral Consortium"] { border-left-color: #00bcd4; }
.session-card[data-type="Social Event"] { border-left-color: #ffab00; }
.session-card[data-type="Treffen"] { border-left-color: #78909c; }
.session-card[data-type="Versammlung"] { border-left-color: #607d8b; }
.session-card[data-type="Abschluss"] { border-left-color: #795548; }

.session-meta {
    display: flex;
    justify-content: space-between;
    font-size: 0.85rem;
    color: #666;
}

.session-id-label {
    font-size: 0.8rem;
    font-weight: 600;
    color: #2196f3;
}

.session-type {
    font-weight: bold;
    text-transform: uppercase;
    font-size: 0.7rem;
    background: #eee;
    padding: 2px 6px;
    border-radius: 4px;
}

.session-title {
    font-size: 1.1rem;
    font-weight: 600;
    line-height: 1.3;
}

.session-title.clickable {
    cursor: pointer;
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 4px;
}

.session-title.clickable:hover {
    color: var(--primary-color);
}

.expand-icon {
    font-size: 20px;
    flex-shrink: 0;
    transition: transform 0.2s;
}

/* Abstract */
.session-abstract {
    margin-top: 8px;
    padding-top: 8px;
    border-top: 1px solid #eee;
}

.session-abstract p {
    font-size: 0.9rem;
    line-height: 1.6;
    color: #444;
    white-space: pre-line;
    margin-bottom: 8px;
}

.presentation-abstract {
    padding: 10px 0;
    border-bottom: 1px solid #f0f0f0;
}

.presentation-abstract:last-child {
    border-bottom: none;
}

.presentation-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 8px;
}

.presentation-title {
    font-weight: 600;
    font-size: 0.95rem;
    margin-bottom: 2px;
    flex: 1;
}

.btn-poster-bookmark,
.btn-talk-bookmark {
    background: none;
    border: none;
    padding: 2px;
    cursor: pointer;
    color: #bbb;
    flex-shrink: 0;
    display: flex;
    align-items: center;
}

.presentation-header .btn-share {
    padding: 2px;
    flex-shrink: 0;
}

.presentation-header .btn-share .material-icons {
    font-size: 20px;
}

.btn-poster-bookmark .material-icons,
.btn-talk-bookmark .material-icons {
    font-size: 20px;
}

.btn-poster-bookmark.active,
.btn-talk-bookmark.active {
    color: var(--accent-color);
}

.btn-poster-bookmark:hover,
.btn-talk-bookmark:hover {
    color: var(--accent-color);
}

/* Poster section in Mein Programm */
.poster-header {
    color: #e91e63;
    border-bottom-color: #e91e63;
}

.presentation-authors {
    font-size: 0.85rem;
    font-style: italic;
    color: #555;
    margin-bottom: 6px;
}

.session-location {
    font-size: 0.9rem;
    color: #666;
    display: flex;
    align-items: center;
    gap: 4px;
}

.session-authors {
    font-size: 0.85rem;
    font-style: italic;
    color: #555;
    margin-top: 5px;
}

.session-chair {
    font-size: 0.85rem;
    color: #555;
    display: flex;
    align-items: center;
    gap: 4px;
    margin-top: 4px;
}

/* Actions */
.card-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 10px;
    border-top: 1px solid #eee;
    padding-top: 10px;
}

.btn-share {
    background: none;
    border: none;
    border-radius: 50%;
    padding: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #999;
}

.btn-share .material-icons {
    font-size: 22px;
}

.btn-share:hover {
    color: var(--primary-color);
}

.btn-bookmark {
    background: none;
    border: none;
    border-radius: 50%;
    padding: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #999;
}

.btn-bookmark .material-icons {
    font-size: 28px;
}

.btn-bookmark.active {
    background-color: transparent;
    color: var(--accent-color);
    border-color: transparent;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background-color: #323232;
    color: white;
    padding: 1rem;
    border-radius: 8px;
    width: 90%;
    max-width: 400px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.3);
    z-index: 2000;
    display: flex;
    justify-content: center;
}


.toast-content {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
}

.toast p { flex: 1; font-size: 0.9rem; }

.close-btn {
    background: none;
    border: none;
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: #888;
}

/* Modal */
.modal {
    display: flex;
    position: fixed; 
    z-index: 3000; 
    left: 0;
    top: 0;
    width: 100%; 
    height: 100%; 
    overflow: auto; 
    background-color: rgba(0,0,0,0.6); 
    align-items: center;
    justify-content: center;
}


.modal-content {
    background-color: #fefefe;
    padding: 20px;
    border-radius: 8px;
    width: 90%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    text-align: center;
    position: relative;
}

.close-modal {
    position: absolute;
    right: 15px;
    top: 10px;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.map-placeholder {
    background-color: #eee;
    height: 200px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    margin: 15px 0;
    border-radius: 4px;
}

.map-icon { font-size: 48px; color: #ccc; }

.btn-primary {
    display: inline-block;
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 4px;
    margin-top: 10px;
    cursor: pointer;
    font-size: 1rem;
}

.btn-secondary {
    background-color: #555;
    margin-left: 8px;
}

.full-width {
    width: 100%;
}

/* Auth Modal Styles */
.auth-content {
    max-width: 350px;
}

.auth-tabs {
    display: flex;
    margin-bottom: 20px;
    border-bottom: 1px solid #ddd;
}

.auth-tab {
    flex: 1;
    background: none;
    border: none;
    padding: 10px;
    cursor: pointer;
    font-size: 1rem;
    color: #666;
    border-bottom: 2px solid transparent;
}

.auth-tab.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
    font-weight: bold;
}

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

.form-group label {
    display: block;
    margin-bottom: 5px;
    color: #555;
    font-size: 0.9rem;
}

.form-group input {
    width: 100%;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 1rem;
}

.error-msg {
    color: #d32f2f;
    font-size: 0.9rem;
    margin-bottom: 10px;
    min-height: 1.2em;
}

.error-msg.success-msg {
    color: #2e7d32;
}

/* Loading State */
.loading-state {
    text-align: center;
    padding: 3rem 1rem;
    color: #888;
}

.loading-state .material-icons {
    font-size: 48px;
    margin-bottom: 15px;
    display: block;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.spinning {
    animation: spin 1.5s linear infinite;
}

/* Hamburger Menu Button */
.hamburger-btn {
    background: none;
    border: none;
    color: white;
    cursor: pointer;
    padding: 5px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-left: 5px;
}

.hamburger-btn .material-icons {
    font-size: 28px;
}

/* Menu Overlay */
.menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 4000;
}

.menu-panel {
    position: absolute;
    top: 0;
    right: 0;
    width: 280px;
    max-width: 80%;
    height: 100%;
    background: white;
    box-shadow: -2px 0 8px rgba(0, 0, 0, 0.3);
    animation: slideIn 0.2s ease-out;
}

@keyframes slideIn {
    from { transform: translateX(100%); }
    to { transform: translateX(0); }
}

.menu-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 20px;
    background-color: var(--primary-color);
    color: white;
    font-size: 1.1rem;
    font-weight: bold;
}

.menu-close-btn {
    background: none;
    border: none;
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
}

.menu-list {
    list-style: none;
    padding: 8px 0;
}

.menu-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 20px;
    cursor: pointer;
    font-size: 1rem;
    color: var(--text-color);
    transition: background-color 0.15s;
}

.menu-item:hover {
    background-color: #f0f0f0;
}

.menu-item .material-icons {
    color: #666;
    font-size: 22px;
}

.menu-divider {
    height: 1px;
    background-color: #e0e0e0;
    margin: 8px 0;
}

.menu-user-info {
    font-weight: bold;
    color: var(--primary-color) !important;
    cursor: default;
}

.menu-user-info .material-icons {
    color: var(--primary-color) !important;
}

/* Info Modal */
.info-modal-content {
    text-align: left;
    max-width: 500px;
}

.info-modal-content h2 {
    margin-bottom: 16px;
    padding-right: 30px;
}

.info-modal-content p {
    margin-bottom: 10px;
    line-height: 1.6;
    font-size: 0.95rem;
}

.info-modal-content ul {
    margin: 8px 0 12px 20px;
    line-height: 1.6;
    font-size: 0.95rem;
}

.info-modal-content a {
    color: var(--primary-color);
}

/* Person Index Modal */
.person-modal-content {
    text-align: left;
    max-width: 600px;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
}

.person-modal-content h2 {
    margin-bottom: 12px;
    padding-right: 30px;
}

.person-search-input {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid #ddd;
    border-radius: 6px;
    font-size: 1rem;
    margin-bottom: 4px;
}

.person-search-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(0, 86, 179, 0.15);
}

.person-count {
    font-size: 0.82rem;
    color: #888;
    margin-bottom: 10px;
}

.person-list {
    overflow-y: auto;
    flex: 1;
    min-height: 0;
}

.person-item {
    border-bottom: 1px solid #f0f0f0;
}

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

.person-header {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 4px 8px;
    padding: 10px 4px;
    cursor: pointer;
    transition: background-color 0.15s;
}

.person-header:hover {
    background-color: #f8f8f8;
}

.person-name {
    font-weight: 600;
    font-size: 0.95rem;
    flex: 1;
}

.person-expand-icon {
    font-size: 20px;
    color: #aaa;
    margin-left: auto;
    flex-shrink: 0;
}

.person-sessions {
    padding: 0 4px 10px 12px;
}

.person-session-ref {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 4px 0;
    border-left: 2px solid #ddd;
    padding-left: 10px;
    margin-bottom: 4px;
}

.person-session-info {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-width: 0;
}

.person-session-time {
    font-size: 0.78rem;
    color: #999;
}

.person-session-title {
    font-size: 0.85rem;
    color: #444;
    line-height: 1.3;
}

.person-session-bookmark {
    background: none;
    border: none;
    padding: 4px;
    cursor: pointer;
    color: #bbb;
    flex-shrink: 0;
    display: flex;
    align-items: center;
}

.person-session-bookmark .material-icons {
    font-size: 22px;
}

.person-session-bookmark.active {
    color: var(--accent-color);
}

.person-session-bookmark:hover {
    color: var(--accent-color);
}

/* Session card highlight animation */
@keyframes highlightFlash {
    0% { background-color: #fff9c4; }
    100% { background-color: var(--card-bg); }
}

.session-card.highlight,
.presentation-abstract.highlight {
    animation: highlightFlash 2s ease-out;
}

/* Clickable author/chair names */
.clickable-name {
    cursor: pointer;
    transition: color 0.15s;
}

.clickable-name:hover {
    color: var(--primary-color);
    text-decoration: underline;
}

/* Clickable session refs in person index */
.clickable-session-ref {
    cursor: pointer;
    transition: background-color 0.15s;
    border-radius: 4px;
    padding: 2px 4px;
    margin: -2px -4px;
}

.clickable-session-ref:hover {
    background-color: #f0f4ff;
}