/* ── AstroSim AI Styling System (Rank 1 Build) ── */

:root {
    --bg-dark: #060814;
    --panel-bg: rgba(10, 14, 35, 0.65);
    --panel-border: rgba(56, 189, 248, 0.15);
    --panel-glow: rgba(56, 189, 248, 0.05);
    
    --color-text: #e2e8f0;
    --color-text-muted: #94a3b8;
    
    --color-primary: #38bdf8;       /* Neon Cyan */
    --color-primary-hover: #0ea5e9;
    --color-accent: #a855f7;        /* Purple */
    --color-success: #10b981;       /* Green */
    --color-danger: #ef4444;        /* Red */
    --color-yellow: #f59e0b;        /* Solar Yellow */
    --color-blue: #3b82f6;          /* Deep Space Blue */
    
    --font-sans: 'Inter', sans-serif;
    --font-mono: 'Roboto Mono', monospace;
    
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset and Core Layout */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-dark);
    color: var(--color-text);
    overflow: hidden;
    height: 100vh;
    width: 100vw;
}

/* Background Space Dust Effect */
.space-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background: radial-gradient(circle at 50% 50%, #0c1033 0%, #060814 80%);
    background-image: 
        radial-gradient(white, rgba(255,255,255,.2) 2px, transparent 40px),
        radial-gradient(white, rgba(255,255,255,.15) 1px, transparent 30px),
        radial-gradient(white, rgba(255,255,255,.1) 2px, transparent 40px);
    background-size: 550px 550px, 350px 350px, 250px 250px;
    background-position: 0 0, 40px 60px, 130px 270px;
    opacity: 0.4;
    animation: slow-pan 120s linear infinite;
}

@keyframes slow-pan {
    from { background-position: 0 0, 40px 60px, 130px 270px; }
    to { background-position: 550px 550px, 390px 410px, 380px 820px; }
}

/* Scrollbars styling */
.scrollable::-webkit-scrollbar {
    width: 6px;
}
.scrollable::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.02);
}
.scrollable::-webkit-scrollbar-thumb {
    background: rgba(56, 189, 248, 0.2);
    border-radius: 3px;
}
.scrollable::-webkit-scrollbar-thumb:hover {
    background: rgba(56, 189, 248, 0.4);
}

/* App Structure Grid */
.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    padding: 1rem;
    gap: 1rem;
}

/* Header */
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 1.5rem;
    background: var(--panel-bg);
    border: 1px solid var(--panel-border);
    border-radius: 12px;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(10px);
}

.brand {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.logo-icon {
    font-size: 2.2rem;
    color: var(--color-primary);
    filter: drop-shadow(0 0 8px rgba(56, 189, 248, 0.4));
    animation: float 4s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-4px); }
}

.brand-text h1 {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: 0.5px;
}

.accent-text {
    color: var(--color-primary);
    text-shadow: 0 0 10px rgba(56, 189, 248, 0.3);
}

.tagline {
    font-size: 0.8rem;
    color: var(--color-text-muted);
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 0.65rem;
}

/* Main Layout Grid */
.app-main {
    display: grid;
    grid-template-columns: 320px 1fr 360px;
    flex: 1;
    gap: 1rem;
    min-height: 0;
}

/* Panels (Left & Right) */
.panel {
    display: flex;
    flex-direction: column;
    background: var(--panel-bg);
    border: 1px solid var(--panel-border);
    border-radius: 16px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(12px);
    overflow: hidden;
}

.panel-header {
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--panel-border);
}

.panel-header h2 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--color-primary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.panel-body {
    flex: 1;
    overflow: hidden;
    padding: 1.25rem;
}

.panel-body.scrollable {
    overflow-y: auto;
}

/* Control Panel Content Groups */
.control-group {
    margin-bottom: 1.5rem;
}

.control-group:last-child {
    margin-bottom: 0;
}

.control-group h3 {
    font-size: 0.9rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    color: var(--color-text-muted);
    margin-bottom: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.4rem;
}

/* Spawner Buttons */
.spawner-tools {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.btn-spawn {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.08);
    color: var(--color-text);
    padding: 0.6rem 0.5rem;
    font-size: 0.85rem;
    font-weight: 500;
    border-radius: 8px;
    cursor: pointer;
    transition: var(--transition-fast);
}

.btn-spawn:hover {
    background: rgba(56, 189, 248, 0.08);
    border-color: rgba(56, 189, 248, 0.3);
}

.btn-spawn.active {
    background: rgba(56, 189, 248, 0.15);
    border-color: var(--color-primary);
    box-shadow: 0 0 10px rgba(56, 189, 248, 0.1);
}

/* Slider Controls */
.param-slider {
    margin-bottom: 0.85rem;
}

.param-slider label {
    display: flex;
    justify-content: space-between;
    font-size: 0.82rem;
    margin-bottom: 0.4rem;
}

.param-slider label span {
    font-family: var(--font-mono);
    color: var(--color-primary);
    font-weight: 600;
}

.param-slider input[type="range"] {
    width: 100%;
    height: 4px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 2px;
    outline: none;
    -webkit-appearance: none;
}

.param-slider input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--color-primary);
    cursor: pointer;
    box-shadow: 0 0 8px var(--color-primary);
    transition: var(--transition-fast);
}

.param-slider input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

/* Labs Presets Cards */
.labs-list {
    display: flex;
    flex-direction: column;
    gap: 0.65rem;
}

.lab-card {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 10px;
    padding: 0.75rem;
    text-align: left;
    cursor: pointer;
    transition: var(--transition-normal);
}

.lab-card:hover {
    background: rgba(56, 189, 248, 0.03);
    border-color: rgba(56, 189, 248, 0.2);
    transform: translateX(2px);
}

.lab-card.active {
    background: linear-gradient(90deg, rgba(56, 189, 248, 0.08) 0%, rgba(168, 85, 247, 0.08) 100%);
    border-color: var(--color-primary);
    box-shadow: 0 0 15px rgba(56, 189, 248, 0.05);
}

.lab-title {
    font-size: 0.88rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: 0.25rem;
}

.lab-desc {
    font-size: 0.75rem;
    color: var(--color-text-muted);
    line-height: 1.3;
}

/* Checkbox Container */
.checkbox-container {
    display: block;
    position: relative;
    padding-left: 28px;
    margin-bottom: 0.65rem;
    cursor: pointer;
    font-size: 0.85rem;
    user-select: none;
    color: var(--color-text);
}

.checkbox-container input {
    position: absolute;
    opacity: 0;
    cursor: pointer;
    height: 0;
    width: 0;
}

.checkmark {
    position: absolute;
    top: 2px;
    left: 0;
    height: 16px;
    width: 16px;
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 4px;
    transition: var(--transition-fast);
}

.checkbox-container:hover input ~ .checkmark {
    border-color: var(--color-primary);
}

.checkbox-container input:checked ~ .checkmark {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
    box-shadow: 0 0 6px var(--color-primary);
}

.checkmark:after {
    content: "";
    position: absolute;
    display: none;
}

.checkbox-container input:checked ~ .checkmark:after {
    display: block;
}

.checkbox-container .checkmark:after {
    left: 5px;
    top: 2px;
    width: 4px;
    height: 8px;
    border: solid black;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}

/* Buttons */
.btn {
    font-family: var(--font-sans);
    font-size: 0.88rem;
    font-weight: 500;
    padding: 0.6rem 1rem;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: var(--transition-fast);
}

.btn-primary {
    background: var(--color-primary);
    color: #000;
    font-weight: 600;
    box-shadow: 0 4px 14px rgba(56, 189, 248, 0.3);
}

.btn-primary:hover {
    background: var(--color-primary-hover);
    box-shadow: 0 4px 20px rgba(56, 189, 248, 0.5);
    transform: translateY(-1px);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--color-text);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.2);
}

.btn-danger {
    background: rgba(239, 68, 68, 0.15);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: var(--color-danger);
}

.btn-danger:hover {
    background: rgba(239, 68, 68, 0.25);
    border-color: var(--color-danger);
}

.btn-block {
    display: flex;
    width: 100%;
}

/* VIEWPORT (CENTER) */
.space-viewport {
    position: relative;
    background: radial-gradient(circle at center, #0c1038 0%, #030510 100%);
    border: 1px solid var(--panel-border);
    border-radius: 20px;
    box-shadow: inset 0 0 40px rgba(0, 0, 0, 0.8), 0 8px 32px rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

#space-canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    cursor: crosshair;
}

/* Viewport HUD Elements */
.viewport-hud {
    position: absolute;
    z-index: 10;
    pointer-events: none;
}

.top-hud {
    top: 1.25rem;
    left: 1.25rem;
    right: 1.25rem;
    display: flex;
    justify-content: space-between;
}

.hud-item {
    background: rgba(6, 8, 20, 0.85);
    border: 1px solid rgba(56, 189, 248, 0.2);
    border-radius: 8px;
    padding: 0.5rem 0.75rem;
    display: flex;
    flex-direction: column;
    min-width: 100px;
    backdrop-filter: blur(8px);
}

.hud-label {
    font-size: 0.65rem;
    text-transform: uppercase;
    color: var(--color-text-muted);
    letter-spacing: 0.5px;
    margin-bottom: 0.15rem;
}

.hud-value {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--color-primary);
    font-family: var(--font-mono);
}

.bottom-hud {
    bottom: 1.25rem;
    left: 50%;
    transform: translateX(-50%);
}

.hud-tip {
    background: rgba(6, 8, 20, 0.85);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 20px;
    padding: 0.4rem 1rem;
    font-size: 0.78rem;
    color: var(--color-text-muted);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    white-space: nowrap;
}

.hud-tip i {
    color: var(--color-primary);
}

/* RIGHT PANEL */
.panel-tabs {
    display: flex;
    border-bottom: 1px solid var(--panel-border);
    background: rgba(0, 0, 0, 0.15);
}

.tab-btn {
    flex: 1;
    background: transparent;
    border: none;
    color: var(--color-text-muted);
    padding: 1rem;
    font-family: var(--font-sans);
    font-weight: 550;
    font-size: 0.9rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: var(--transition-fast);
}

.tab-btn:hover {
    color: var(--color-text);
    background: rgba(255, 255, 255, 0.02);
}

.tab-btn.active {
    color: var(--color-primary);
    border-bottom: 2px solid var(--color-primary);
    background: rgba(56, 189, 248, 0.02);
    text-shadow: 0 0 8px rgba(56, 189, 248, 0.15);
}

.flex-container {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.tab-content {
    display: none;
    flex: 1;
    flex-direction: column;
    min-height: 0;
}

.tab-content.active-content {
    display: flex;
}

/* Chat Thread */
.chat-thread {
    flex: 1;
    overflow-y: auto;
    padding: 0.25rem 0.25rem 1rem 0.25rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.message {
    max-width: 85%;
    padding: 0.75rem 0.95rem;
    border-radius: 12px;
    font-size: 0.85rem;
    line-height: 1.45;
}

.message-sender {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.4px;
    margin-bottom: 0.35rem;
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.message-text strong {
    color: var(--color-primary);
}

.message-ai {
    background: rgba(56, 189, 248, 0.06);
    border: 1px solid rgba(56, 189, 248, 0.15);
    border-top-left-radius: 2px;
    align-self: flex-start;
}

.message-ai .message-sender {
    color: var(--color-primary);
}

.message-user {
    background: rgba(168, 85, 247, 0.08);
    border: 1px solid rgba(168, 85, 247, 0.2);
    border-top-right-radius: 2px;
    align-self: flex-end;
}

.message-user .message-sender {
    color: var(--color-accent);
}

/* Typing indicator spinner */
.typing-indicator i {
    animation: rotate 1.5s linear infinite;
}

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

/* Suggestions buttons */
.chat-suggestions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    padding: 0.5rem 0;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    margin-bottom: 0.5rem;
}

.suggestion-btn {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.06);
    color: var(--color-text-muted);
    font-size: 0.72rem;
    padding: 0.35rem 0.65rem;
    border-radius: 12px;
    cursor: pointer;
    transition: var(--transition-fast);
}

.suggestion-btn:hover {
    background: rgba(56, 189, 248, 0.05);
    border-color: rgba(56, 189, 248, 0.25);
    color: var(--color-text);
}

/* Chat Input Bar */
.chat-input-container {
    display: flex;
    gap: 0.5rem;
    background: rgba(6, 8, 20, 0.5);
    border: 1px solid var(--panel-border);
    border-radius: 8px;
    padding: 0.35rem;
}

.chat-input-container input {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    color: var(--color-text);
    font-size: 0.85rem;
    padding: 0.25rem 0.5rem;
}

.chat-input-container input::placeholder {
    color: rgba(255, 255, 255, 0.25);
}

#chat-send-btn {
    padding: 0.5rem 0.75rem;
    font-size: 0.8rem;
}

/* MATH BLACKBOARD (Tab 2) */
.blackboard-container {
    padding-right: 0.25rem;
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
    height: 100%;
}

.blackboard-intro {
    font-size: 0.82rem;
    color: var(--color-text-muted);
    line-height: 1.4;
}

.math-card {
    background: rgba(0, 0, 0, 0.25);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 12px;
    padding: 1rem;
}

.math-title {
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--color-primary);
    text-transform: uppercase;
    letter-spacing: 0.4px;
    margin-bottom: 0.6rem;
}

.math-formula {
    background: rgba(0, 0, 0, 0.2);
    padding: 0.75rem;
    border-radius: 8px;
    text-align: center;
    margin-bottom: 0.75rem;
    overflow-x: auto;
}

.math-live-values {
    font-size: 0.78rem;
    color: var(--color-text-muted);
}

.math-live-values strong {
    display: block;
    margin-bottom: 0.3rem;
    color: var(--color-text);
}

.mono-font {
    font-family: var(--font-mono);
    color: var(--color-success);
    background: rgba(16, 185, 129, 0.04);
    border: 1px solid rgba(16, 185, 129, 0.15);
    padding: 0.5rem 0.75rem;
    border-radius: 6px;
    word-break: break-all;
    line-height: 1.5;
}

/* BADGES & UTILITIES */
.badge-online {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.25);
    color: var(--color-success);
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.3rem 0.65rem;
    border-radius: 16px;
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
}

.pulse-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background-color: var(--color-success);
    box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7);
    animation: pulse 1.6s infinite;
}

@keyframes pulse {
    0% {
        transform: scale(0.95);
        box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7);
    }
    70% {
        transform: scale(1);
        box-shadow: 0 0 0 5px rgba(16, 185, 129, 0);
    }
    100% {
        transform: scale(0.95);
        box-shadow: 0 0 0 0 rgba(16, 185, 129, 0);
    }
}

.text-yellow { color: var(--color-yellow); }
.text-blue { color: var(--color-blue); }
.mt-3 { margin-top: 0.75rem; }

/* SETTINGS MODAL */
.modal-backdrop {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(3, 5, 15, 0.8);
    backdrop-filter: blur(8px);
    z-index: 100;
    display: none;
    align-items: center;
    justify-content: center;
}

.modal-backdrop.show {
    display: flex;
}

.modal-box {
    background: #0b0e25;
    border: 1px solid var(--panel-border);
    border-radius: 16px;
    width: 90%;
    max-width: 480px;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.8), 0 0 40px rgba(56, 189, 248, 0.1);
    overflow: hidden;
    animation: zoom-in 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes zoom-in {
    from { opacity: 0; transform: scale(0.95); }
    to { opacity: 1; transform: scale(1); }
}

.modal-header {
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--panel-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h2 {
    font-size: 1.15rem;
    color: var(--color-primary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.modal-close {
    background: transparent;
    border: none;
    color: var(--color-text-muted);
    font-size: 1.5rem;
    cursor: pointer;
    transition: var(--transition-fast);
}

.modal-close:hover {
    color: var(--color-text);
}

.modal-body {
    padding: 1.5rem;
}

.modal-body p {
    font-size: 0.85rem;
    color: var(--color-text-muted);
    line-height: 1.45;
    margin-bottom: 1.25rem;
}

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

.form-group label {
    font-size: 0.85rem;
    font-weight: 550;
    color: var(--color-text);
}

.form-group input {
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 8px;
    padding: 0.65rem 0.85rem;
    color: var(--color-text);
    font-family: var(--font-sans);
    font-size: 0.85rem;
    outline: none;
    transition: var(--transition-fast);
}

.form-group input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 8px rgba(56, 189, 248, 0.2);
}

.form-group small {
    font-size: 0.72rem;
    color: var(--color-text-muted);
    line-height: 1.35;
}

.modal-footer {
    padding: 1rem 1.5rem;
    background: rgba(0, 0, 0, 0.15);
    border-top: 1px solid var(--panel-border);
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
}

/* ── INTERACTIVE ONBOARDING TOUR OVERLAY ── */
.tour-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(3, 5, 15, 0.85);
    backdrop-filter: blur(12px);
    z-index: 200;
    display: flex;
    align-items: center;
    justify-content: center;
}

.tour-card {
    background: #0b0e25;
    border: 1px solid var(--panel-border);
    border-radius: 20px;
    width: 90%;
    max-width: 520px;
    box-shadow: 0 25px 60px rgba(0, 0, 0, 0.9), 0 0 50px rgba(56, 189, 248, 0.15);
    overflow: hidden;
    animation: zoom-in 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    padding: 2rem;
}

.tour-header h2 {
    font-size: 1.4rem;
    color: var(--color-primary);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    border-bottom: 1px solid var(--panel-border);
    padding-bottom: 0.75rem;
}

.tour-body p {
    font-size: 0.92rem;
    color: var(--color-text);
    line-height: 1.5;
    margin-bottom: 1.25rem;
}

.tour-body ol {
    margin-left: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    font-size: 0.88rem;
    color: var(--color-text-muted);
}

.tour-body ol strong {
    color: var(--color-primary);
}

.tour-footer {
    margin-top: 1.75rem;
    display: flex;
    justify-content: flex-end;
}

/* ── RESPONSIVE MEDIA QUERIES (Zero-Overflow Grid Adjustments) ── */
@media (max-width: 1100px) {
    .app-main {
        grid-template-columns: 280px 1fr 320px;
        gap: 0.75rem;
    }
    .header-actions .btn {
        padding: 0.5rem 0.75rem;
        font-size: 0.8rem;
    }
}

@media (max-width: 960px) {
    body {
        overflow-y: auto;
        height: auto;
    }
    
    .app-container {
        height: auto;
        overflow-y: auto;
        padding: 0.5rem;
        gap: 0.75rem;
    }

    .app-main {
        grid-template-columns: 1fr;
        grid-template-rows: auto 500px auto;
        height: auto;
        gap: 0.75rem;
    }
    
    .space-viewport {
        grid-row: 1; /* Space Simulator stays on top for mobile views */
        height: 450px;
    }
    
    .control-panel {
        grid-row: 2;
        height: 520px;
    }
    
    .tutor-panel {
        grid-row: 3;
        height: 520px;
    }
    
    .app-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
        padding: 1rem;
    }
    
    .header-actions {
        width: 100%;
        flex-wrap: wrap;
        gap: 0.5rem;
    }
    
    .header-actions .btn {
        flex: 1;
        min-width: 110px;
    }
}