/* Global Variable Setup */
:root {
    --bg-dark: #080C14;
    --bg-darker: #04060A;
    --bg-card: rgba(17, 24, 39, 0.6);
    --bg-card-hover: rgba(28, 38, 57, 0.7);
    --border-color: rgba(255, 255, 255, 0.08);
    
    --cyan-primary: #00e5ff;
    --cyan-dark: #008ba3;
    --cyan-glow: rgba(0, 229, 255, 0.25);
    
    --orange-primary: #ff5722;
    --orange-dark: #b92000;
    --orange-glow: rgba(255, 87, 34, 0.25);
    
    --text-color: #f1f5f9;
    --text-muted: #94a3b8;
    --accent-blue: #3b82f6;
    --green-success: #10b981;
    --red-alert: #ef4444;
    --panel-divider: rgba(255, 255, 255, 0.05);
}

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

body {
    font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-color);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

/* Header Styling */
.app-header {
    background-color: rgba(4, 6, 10, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    padding: 0.75rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 1000;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-family: 'Outfit', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.logo .cooling-icon {
    color: var(--cyan-primary);
    filter: drop-shadow(0 0 8px var(--cyan-glow));
}

.logo .highlight {
    color: var(--orange-primary);
}

.animate-spin-slow {
    animation: spin 8s linear infinite;
}

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

/* Selector Buttons */
.view-selector {
    display: flex;
    background: rgba(255, 255, 255, 0.05);
    padding: 4px;
    border-radius: 30px;
    border: 1px solid var(--border-color);
}

.selector-btn {
    background: none;
    border: none;
    color: var(--text-muted);
    padding: 0.5rem 1.25rem;
    font-weight: 600;
    font-size: 0.875rem;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.selector-btn:hover {
    color: var(--text-color);
}

.selector-btn.active {
    background-color: var(--cyan-primary);
    color: var(--bg-darker);
    box-shadow: 0 0 12px var(--cyan-glow);
}

#btn-instructor.active {
    background-color: var(--orange-primary);
    color: white;
    box-shadow: 0 0 12px var(--orange-glow);
}

#btn-student.active {
    background-color: var(--accent-blue);
    color: white;
    box-shadow: 0 0 12px rgba(59, 130, 246, 0.4);
}

.connection-status {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
}

.status-dot.online {
    background-color: var(--green-success);
    box-shadow: 0 0 8px var(--green-success);
}

/* Workspace Panels */
.workspace {
    display: flex;
    flex: 1;
    width: 100%;
    position: relative;
}

.panel {
    transition: all 0.4s ease;
    overflow-y: auto;
    padding: 1.5rem;
    height: calc(100vh - 65px);
}

/* Default Dual Mode Layout */
.workspace.mode-dual .panel {
    width: 50%;
}

.workspace.mode-dual #pane-instructor {
    border-right: 1px solid var(--panel-divider);
}

.workspace.mode-instructor #pane-instructor {
    width: 100%;
}

.workspace.mode-instructor #pane-student {
    display: none;
}

.workspace.mode-student #pane-student {
    width: 100%;
}

.workspace.mode-student #pane-instructor {
    display: none;
}

/* Card Styling */
.card {
    background: var(--bg-card);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    transition: transform 0.2s ease, border-color 0.2s ease;
}

.card:hover {
    border-color: rgba(255, 255, 255, 0.15);
}

.panel-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.panel-header h2 {
    font-family: 'Outfit', sans-serif;
    font-size: 1.25rem;
    font-weight: 600;
}

.panel-badge {
    padding: 0.25rem 0.75rem;
    border-radius: 30px;
    font-size: 0.75rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 0.35rem;
}

.badge-teacher {
    background: rgba(255, 87, 34, 0.15);
    color: var(--orange-primary);
    border: 1px solid rgba(255, 87, 34, 0.3);
}

.badge-student {
    background: rgba(59, 130, 246, 0.15);
    color: var(--accent-blue);
    border: 1px solid rgba(59, 130, 246, 0.3);
}

/* Grid Layout for Instructor Panel */
.grid-layout {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 1.5rem;
    align-items: start;
}

/* Sidebar Contenido Curricular */
.sidebar {
    height: calc(100vh - 150px);
    overflow-y: auto;
    padding: 1rem;
}

.sidebar h3 {
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    color: var(--text-muted);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.curriculum-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.curriculum-unit-title {
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--orange-primary);
    margin-top: 0.5rem;
    margin-bottom: 0.25rem;
}

.curriculum-item {
    padding: 0.75rem;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid transparent;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-muted);
    transition: all 0.2s ease;
}

.curriculum-item:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-color);
}

.curriculum-item.active {
    background: rgba(255, 87, 34, 0.1);
    border-color: rgba(255, 87, 34, 0.4);
    color: var(--text-color);
}

/* Slides and Topic Views */
.slide-controller {
    border-left: 4px solid var(--orange-primary);
}

.card-header {
    margin-bottom: 1.25rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.75rem;
}

.card-subtitle {
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--text-muted);
    font-weight: 600;
}

.card-header h4 {
    font-size: 1.15rem;
    margin-top: 0.25rem;
}

.topic-content-wrapper {
    font-size: 0.95rem;
    line-height: 1.6;
    margin-bottom: 1.5rem;
    min-height: 120px;
}

.topic-content-wrapper p {
    margin-bottom: 0.75rem;
    color: var(--text-color);
}

.topic-content-wrapper ul {
    margin-left: 1.5rem;
    margin-bottom: 0.75rem;
}

.topic-content-wrapper li {
    margin-bottom: 0.35rem;
}

.instructor-action-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid var(--border-color);
    padding-top: 1rem;
}

.action-btn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 0.5rem 1rem;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.action-btn:hover {
    background: rgba(255, 255, 255, 0.1);
}

.action-btn.next-btn {
    background-color: var(--orange-primary);
    border-color: var(--orange-primary);
    color: white;
}

.action-btn.next-btn:hover {
    background-color: var(--orange-dark);
}

.topic-indicator {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* Simulator controls styling */
.simulator-card {
    border-left: 4px solid var(--cyan-primary);
}

.simulator-controls-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.25rem;
    margin-top: 1rem;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.control-group label {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-muted);
}

.slider-val-wrapper {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.slider-val-wrapper input[type="range"] {
    flex: 1;
    accent-color: var(--cyan-primary);
}

.val-display {
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 700;
    min-width: 75px;
    text-align: center;
}

.badge-cold {
    background: rgba(0, 229, 255, 0.15);
    color: var(--cyan-primary);
    border: 1px solid rgba(0, 229, 255, 0.3);
}

.badge-hot {
    background: rgba(255, 87, 34, 0.15);
    color: var(--orange-primary);
    border: 1px solid rgba(255, 87, 34, 0.3);
}

select {
    background: rgba(4, 6, 10, 0.8);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 0.5rem;
    border-radius: 8px;
    font-size: 0.85rem;
    outline: none;
    cursor: pointer;
}

select:focus {
    border-color: var(--cyan-primary);
}

/* Quizzes section styling */
.quiz-card {
    border-left: 4px solid var(--green-success);
}

.live-pulse {
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--green-success);
    display: flex;
    align-items: center;
    gap: 0.35rem;
    float: right;
    margin-top: -1.75rem;
}

.pulse-dot {
    width: 6px;
    height: 6px;
    background-color: var(--green-success);
    border-radius: 50%;
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0% { transform: scale(0.9); opacity: 0.6; }
    50% { transform: scale(1.25); opacity: 1; }
    100% { transform: scale(0.9); opacity: 0.6; }
}

.quiz-selector-wrapper {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
}

.quiz-selector-wrapper select {
    flex: 1;
}

.launch-btn {
    background-color: var(--green-success);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.85rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.4rem;
    transition: background 0.2s ease;
}

.launch-btn:hover {
    background-color: #0c9e6d;
}

.launch-btn.stop-btn {
    background-color: var(--red-alert);
}

.launch-btn.stop-btn:hover {
    background-color: #c53030;
}

.quiz-results-live {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1rem;
    margin-top: 1rem;
}

.quiz-question-text {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
}

.chart-container {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
}

.bar-result {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.option-label {
    font-size: 0.8rem;
    font-weight: 700;
    width: 15px;
}

.bar-track {
    flex: 1;
    height: 16px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 8px;
    overflow: hidden;
}

.bar-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--green-success), #34d399);
    width: 0%;
    border-radius: 8px;
    transition: width 0.5s cubic-bezier(0.1, 0.8, 0.25, 1);
}

.percentage {
    font-size: 0.8rem;
    font-weight: 600;
    width: 35px;
    text-align: right;
}

.quiz-stats {
    display: flex;
    justify-content: space-between;
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* ================================================================= */
/* STUDENT SIDE                                                     */
/* ================================================================= */
.student-slide-container {
    border-left: 4px solid var(--accent-blue);
}

.slide-header {
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.75rem;
    margin-bottom: 1.25rem;
}

.slide-unit {
    font-size: 0.75rem;
    color: var(--accent-blue);
    font-weight: 700;
    letter-spacing: 0.5px;
}

.slide-title {
    font-size: 1.35rem;
    font-family: 'Outfit', sans-serif;
    margin-top: 0.2rem;
}

.waiting-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem 0;
    color: var(--text-muted);
    gap: 1rem;
}

.waiting-state i {
    font-size: 2rem;
    color: var(--accent-blue);
}

/* Student Live Simulator View */
.student-simulator-view {
    margin-top: 1rem;
    border-top: 1px solid var(--border-color);
    padding-top: 1rem;
}

.simulator-layout {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 1.5rem;
}

.schematic-container, .ph-diagram-container {
    background: rgba(0, 0, 0, 0.15);
    border-radius: 8px;
    padding: 1rem;
    border: 1px solid rgba(255, 255, 255, 0.03);
}

.schematic-container h5, .ph-diagram-container h5 {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 1rem;
    text-transform: uppercase;
}

/* Schematic Loop */
.refrigeration-loop {
    display: grid;
    grid-template-columns: 80px 40px 80px;
    grid-template-rows: 60px 40px 60px;
    align-items: center;
    justify-content: center;
    padding: 1rem 0;
}

.loop-node {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 0.4rem;
    text-align: center;
    font-size: 0.7rem;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.loop-node .node-icon {
    font-size: 0.95rem;
    margin-bottom: 0.15rem;
}

.loop-node .node-label {
    font-weight: 600;
}

.loop-node .node-val {
    font-weight: 700;
    font-size: 0.65rem;
    margin-top: 0.1rem;
}

.node-evap {
    grid-column: 1;
    grid-row: 1;
    border-color: var(--cyan-primary);
    box-shadow: 0 0 10px rgba(0, 229, 255, 0.1);
}

.node-comp {
    grid-column: 3;
    grid-row: 1;
}

.node-cond {
    grid-column: 3;
    grid-row: 3;
    border-color: var(--orange-primary);
    box-shadow: 0 0 10px rgba(255, 87, 34, 0.1);
}

.node-valve {
    grid-column: 1;
    grid-row: 3;
}

/* Flow lines */
.flow-line {
    position: relative;
}

.flow-right {
    grid-column: 2;
    grid-row: 1;
    height: 2px;
    border-top: 2px dashed var(--text-muted);
}

.flow-down {
    grid-column: 3;
    grid-row: 2;
    width: 2px;
    height: 100%;
    margin: 0 auto;
    border-left: 2px dashed var(--orange-primary);
}

.flow-left {
    grid-column: 2;
    grid-row: 3;
    height: 2px;
    border-top: 2px dashed var(--accent-blue);
}

.flow-up {
    grid-column: 1;
    grid-row: 2;
    width: 2px;
    height: 100%;
    margin: 0 auto;
    border-left: 2px dashed var(--cyan-primary);
}

/* SVG P-h chart dynamic styling */
.ph-svg {
    background-color: rgba(4, 6, 10, 0.5);
    border-radius: 6px;
    width: 100%;
    height: auto;
}

.sim-metrics {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    margin-top: 0.75rem;
}

.metric {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    border-bottom: 1px dashed rgba(255,255,255,0.05);
    padding-bottom: 0.25rem;
}

.metric-label {
    color: var(--text-muted);
}

.metric-value {
    font-weight: 700;
    color: var(--cyan-primary);
}

/* Student Quiz Card */
.student-quiz-container {
    border-left: 4px solid var(--green-success);
    background: rgba(16, 185, 129, 0.04);
}

.quiz-badge {
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--green-success);
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.35rem;
}

.student-quiz-container h3 {
    font-size: 1.05rem;
    margin-bottom: 1rem;
}

.quiz-options {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.quiz-opt-btn {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 0.75rem 1rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    text-align: left;
    transition: all 0.2s ease;
}

.quiz-opt-btn:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.2);
}

.quiz-opt-btn:active {
    background: rgba(255, 255, 255, 0.08);
}

.quiz-feedback-state {
    padding: 0.5rem 0;
    color: var(--green-success);
    font-size: 0.9rem;
    font-weight: 600;
}

/* Q&A / Consultas Section */
.student-qa h4 {
    font-size: 0.9rem;
    text-transform: uppercase;
    color: var(--text-muted);
    letter-spacing: 0.5px;
    margin-bottom: 0.75rem;
}

.qa-input-wrapper {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.qa-input-wrapper input {
    flex: 1;
    background: rgba(4, 6, 10, 0.5);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 0.5rem 0.75rem;
    color: var(--text-color);
    outline: none;
    font-size: 0.85rem;
}

.qa-input-wrapper input:focus {
    border-color: var(--accent-blue);
}

.qa-send-btn {
    background-color: var(--accent-blue);
    border: none;
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    font-size: 0.85rem;
}

.qa-send-btn:hover {
    background-color: #2563eb;
}

.qa-feed {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    max-height: 150px;
    overflow-y: auto;
}

.no-messages-placeholder {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-align: center;
    padding: 0.5rem;
}

.qa-item {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 0.5rem;
    font-size: 0.8rem;
}

.qa-item-header {
    display: flex;
    justify-content: space-between;
    font-weight: 700;
    color: var(--accent-blue);
    margin-bottom: 0.15rem;
    font-size: 0.75rem;
}

.qa-item-time {
    color: var(--text-muted);
    font-weight: 400;
}

/* Floating Info Box for Demonstrator */
.demo-info-floating {
    position: fixed;
    bottom: 1.5rem;
    right: 1.5rem;
    z-index: 2000;
    max-width: 350px;
    background: rgba(11, 15, 25, 0.95);
    border: 1px solid var(--cyan-primary);
    box-shadow: 0 4px 24px rgba(0, 229, 255, 0.2);
    border-radius: 12px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.demo-info-floating.collapsed {
    max-width: 48px;
    max-height: 48px;
    border-radius: 50%;
    overflow: hidden;
    border-color: var(--border-color);
    box-shadow: 0 4px 12px rgba(0,0,0,0.5);
}

.info-toggle {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--cyan-primary);
    font-size: 1.25rem;
}

.demo-info-floating.collapsed .info-toggle {
    color: var(--text-muted);
}

.demo-info-floating.collapsed .info-panel-content {
    display: none;
}

.info-panel-content {
    padding: 1rem;
    border-top: 1px solid var(--border-color);
}

.info-panel-content h4 {
    font-family: 'Outfit', sans-serif;
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
    color: var(--cyan-primary);
}

.info-panel-content p {
    font-size: 0.75rem;
    line-height: 1.4;
    margin-bottom: 0.75rem;
}

.info-panel-content ul {
    font-size: 0.75rem;
    margin-left: 1rem;
    margin-bottom: 0.75rem;
}

.info-panel-content li {
    margin-bottom: 0.25rem;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .workspace.mode-dual {
        flex-direction: column;
    }
    .workspace.mode-dual .panel {
        width: 100%;
        height: auto;
    }
    .grid-layout {
        grid-template-columns: 1fr;
    }
    .sidebar {
        height: auto;
    }
    .simulator-layout {
        grid-template-columns: 1fr;
    }
}

/* ================================================================= */
/* FORMULA DISPLAY & STUDENT ACTIVITY CARDS Styling                   */
/* ================================================================= */

.formula-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 12px;
    margin-top: 8px;
}

.formula-item {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 12px;
    display: flex;
    flex-direction: column;
    gap: 6px;
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.formula-item:hover {
    background: rgba(255, 255, 255, 0.04);
    border-color: rgba(59, 130, 246, 0.35);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.1);
    transform: translateY(-2px);
}

.math-expr {
    font-family: 'Outfit', sans-serif;
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 600;
}

.math-calc {
    font-family: 'Outfit', sans-serif;
    font-size: 0.85rem;
    color: var(--text-color);
    line-height: 1.4;
}

.math-calc strong {
    color: var(--cyan-primary);
    font-size: 1rem;
    filter: drop-shadow(0 0 4px var(--cyan-glow));
}

.activity-card-student {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 15px;
    margin-bottom: 10px;
    display: flex;
    flex-direction: column;
    gap: 10px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.activity-card-student:hover {
    border-color: rgba(255, 87, 34, 0.35);
    background: rgba(255, 87, 34, 0.02);
    box-shadow: 0 4px 12px rgba(255, 87, 34, 0.08);
}

/* ================================================================= */
/* STARTUP GATE / LOGIN SCREEN Styling                               */
/* ================================================================= */

.startup-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(4, 6, 10, 0.96);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    z-index: 9999;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    transition: opacity 0.4s ease, visibility 0.4s ease;
}

.startup-overlay.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.startup-card {
    background: rgba(17, 24, 39, 0.65);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 20px;
    padding: 2.5rem 2rem;
    width: 100%;
    max-width: 540px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.6), 
                0 0 40px rgba(0, 229, 255, 0.03);
    text-align: center;
    animation: fadeIn 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

.startup-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    font-family: 'Outfit', sans-serif;
    font-size: 2.25rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    margin-bottom: 2rem;
}

.startup-logo .cooling-icon {
    color: var(--cyan-primary);
    filter: drop-shadow(0 0 10px var(--cyan-glow));
}

.startup-logo .highlight {
    color: var(--orange-primary);
}

.startup-screen {
    display: none;
    width: 100%;
}

.startup-screen.active {
    display: block;
    animation: slideUpFade 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.startup-card h2 {
    font-family: 'Outfit', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.startup-subtitle {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 2rem;
}

/* Role Grid Layout */
.role-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.25rem;
}

@media (max-width: 520px) {
    .role-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    .startup-card {
        padding: 2rem 1.25rem;
    }
}

.role-option {
    cursor: pointer;
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 1.5rem 1.25rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.role-option:hover {
    background: rgba(255, 255, 255, 0.04);
    transform: translateY(-4px);
}

.role-icon-wrapper {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.05);
    margin-bottom: 0.25rem;
    transition: all 0.3s ease;
}

/* Student Glow styles */
.student-option .role-icon-wrapper {
    color: var(--cyan-primary);
    border-color: rgba(0, 229, 255, 0.2);
}

.student-option:hover {
    border-color: rgba(0, 229, 255, 0.4);
    box-shadow: 0 10px 25px rgba(0, 229, 255, 0.1);
}

.student-option:hover .role-icon-wrapper {
    background: var(--cyan-primary);
    color: #04060a;
    box-shadow: 0 0 15px var(--cyan-glow);
}

/* Instructor Glow styles */
.instructor-option .role-icon-wrapper {
    color: var(--orange-primary);
    border-color: rgba(255, 87, 34, 0.2);
}

.instructor-option:hover {
    border-color: rgba(255, 87, 34, 0.4);
    box-shadow: 0 10px 25px rgba(255, 87, 34, 0.1);
}

.instructor-option:hover .role-icon-wrapper {
    background: var(--orange-primary);
    color: #ffffff;
    box-shadow: 0 0 15px var(--orange-glow);
}

.role-option h3 {
    font-family: 'Outfit', sans-serif;
    font-size: 1.15rem;
    font-weight: 600;
}

.role-option p {
    font-size: 0.75rem;
    color: var(--text-muted);
    line-height: 1.4;
    flex-grow: 1;
    margin-bottom: 0.5rem;
}

.btn-role-action {
    font-size: 0.75rem;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: auto;
}

.student-option .btn-role-action {
    color: var(--cyan-primary);
}

.instructor-option .btn-role-action {
    color: var(--orange-primary);
}

/* Auth / Password Form styling */
.auth-form-group {
    margin-bottom: 1.25rem;
    text-align: left;
}

.auth-form-group label {
    display: block;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.auth-form-group label i {
    margin-right: 5px;
    font-size: 0.85rem;
}

.auth-form-group input {
    width: 100%;
    padding: 0.8rem 1rem;
    background: rgba(4, 6, 10, 0.6);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-color);
    font-family: inherit;
    font-size: 0.9rem;
    transition: all 0.2s ease;
}

.auth-form-group input:focus {
    outline: none;
    border-color: var(--orange-primary);
    box-shadow: 0 0 8px var(--orange-glow);
}

.auth-error {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.2);
    color: var(--red-alert);
    padding: 0.75rem 1rem;
    border-radius: 8px;
    font-size: 0.8rem;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    text-align: left;
    animation: shake 0.3s ease;
}

.auth-actions {
    display: flex;
    gap: 12px;
    margin-top: 1.5rem;
}

.auth-actions .action-btn {
    flex: 1;
    justify-content: center;
    padding: 0.8rem 1.5rem;
    font-size: 0.9rem;
}

.auth-actions .btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-color);
    border: 1px solid var(--border-color);
}

.auth-actions .btn-secondary:hover {
    background: rgba(255, 255, 255, 0.08);
}

.auth-actions .btn-primary {
    background: var(--orange-primary);
    color: #ffffff;
    border: 1px solid var(--orange-dark);
}

.auth-actions .btn-primary:hover {
    background: var(--orange-dark);
    box-shadow: 0 0 12px var(--orange-glow);
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideUpFade {
    from { opacity: 0; transform: translateY(15px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    75% { transform: translateX(5px); }
}