:root {
    --bg-color: #1e1e1e;
    --bg-soft: #252525;
    --text-color: #f0f0f0;
    --muted-text: #b7b7b7;
    --terminal-bg: #121212;
    --terminal-text: #33ff33;
    --terminal-prompt: #33aaff;
    --accent-color: #ffcc00;
    --accent-soft: rgba(255, 204, 0, 0.12);
    --menu-bg: #2a2a2a;
    --border-color: rgba(255, 255, 255, 0.08);
    --error-color: #ff3333;
    --success-color: #33cc33;
    --shadow-lg: 0 18px 40px rgba(0, 0, 0, 0.28);
    --shadow-md: 0 8px 20px rgba(0, 0, 0, 0.22);
    --radius-lg: 24px;
    --radius-md: 16px;
    --radius-sm: 10px;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;
    font-family: "Courier New", monospace;
    color: var(--text-color);
    background:
        radial-gradient(circle at top left, rgba(51, 170, 255, 0.16), transparent 28%),
        radial-gradient(circle at top right, rgba(255, 204, 0, 0.16), transparent 30%),
        linear-gradient(180deg, #212121 0%, #161616 100%);
    display: flex;
    flex-direction: column;
}

.site-header,
.site-footer {
    background: rgba(42, 42, 42, 0.88);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--border-color);
}

.site-header {
    padding: 1.4rem 1rem;
    box-shadow: var(--shadow-md);
}

.header-copy,
.site-footer {
    max-width: 1240px;
    margin: 0 auto;
}

.eyebrow,
.section-kicker,
.card-label,
.stat-label {
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-size: 0.78rem;
}

.eyebrow,
.section-kicker,
.card-label {
    color: var(--accent-color);
}

.site-header h1,
.dashboard-top h2,
.intro-copy h2 {
    margin: 0.25rem 0 0.5rem;
}

.header-subtitle,
.author-line,
.intro-copy p,
.command-description,
.next-unlock-text,
.stat-label {
    color: var(--muted-text);
}

.container {
    width: min(1240px, calc(100% - 2rem));
    margin: 0 auto;
    padding: 1.5rem 0 2rem;
    flex: 1;
}

.intro-screen {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.intro-hero {
    display: grid;
    grid-template-columns: 1.25fr 1fr;
    gap: 1.5rem;
    align-items: stretch;
}

.intro-copy,
.intro-terminal-card,
.dashboard-panel,
.lesson-panel,
.terminal-panel,
.modal,
.flag-input-container {
    background: rgba(42, 42, 42, 0.9);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-lg);
}

.intro-copy,
.dashboard-panel,
.lesson-panel,
.terminal-panel {
    border-radius: var(--radius-lg);
}

.intro-copy {
    padding: 2rem;
}

.intro-pill,
.tag,
.flag,
.level-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 999px;
}

.intro-pill {
    background: var(--accent-soft);
    color: var(--accent-color);
    padding: 0.45rem 0.9rem;
    font-size: 0.84rem;
}

.intro-actions,
.dashboard-actions,
.flag-btns,
.lesson-meta,
.terminal-controls,
.panel-tags {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.intro-terminal-card,
.terminal-panel {
    overflow: hidden;
}

.terminal-header {
    display: flex;
    align-items: center;
    gap: 0.9rem;
    padding: 0.9rem 1.1rem;
    border-bottom: 1px solid var(--border-color);
    background: rgba(18, 18, 18, 0.65);
}

.terminal-controls {
    gap: 0.45rem;
}

.terminal-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.terminal-dot.red {
    background: #ff5f56;
}

.terminal-dot.yellow {
    background: #ffbd2e;
}

.terminal-dot.green {
    background: #27c93f;
}

.terminal-label {
    color: var(--muted-text);
    font-size: 0.9rem;
}

.terminal-preview {
    padding: 1.25rem;
    color: var(--terminal-text);
    line-height: 1.7;
}

.prompt-preview,
.prompt {
    color: var(--terminal-prompt);
}

.intro-steps,
.stats-grid {
    display: grid;
    gap: 1rem;
}

.intro-steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
}

.intro-card,
.stat-card,
.progress-card,
.lesson-card,
.hint-box,
.feedback-panel,
.level-btn,
.command-list-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
}

.intro-card,
.stat-card,
.progress-card,
.lesson-card,
.hint-box,
.feedback-panel,
.command-list-card {
    border-radius: var(--radius-md);
    padding: 1.1rem 1.15rem;
}

.intro-card i {
    font-size: 1.2rem;
    color: var(--accent-color);
}

.author-line {
    text-align: center;
    margin: 0;
}

.dashboard-panel {
    padding: 1.4rem;
    margin-bottom: 1.4rem;
}

.dashboard-top,
.level-info {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    flex-wrap: wrap;
}

.dashboard-heading h2 {
    margin-bottom: 0.2rem;
}

.dashboard-subtitle {
    margin: 0;
    color: var(--muted-text);
    max-width: 720px;
    line-height: 1.5;
}

.level-selector {
    display: flex;
    gap: 0.8rem;
    flex-wrap: wrap;
    margin: 1.2rem 0;
}

.level-btn {
    border: 1px solid rgba(255, 204, 0, 0.5);
    color: var(--text-color);
    padding: 0.8rem 1.15rem;
    cursor: pointer;
    transition: transform 0.2s ease, background-color 0.2s ease, border-color 0.2s ease;
}

.level-btn:hover,
.level-btn.active {
    background: var(--accent-color);
    color: var(--bg-color);
    transform: translateY(-2px);
}

.level-btn.locked {
    opacity: 0.5;
    cursor: not-allowed;
    border-color: rgba(255, 255, 255, 0.15);
}

.level-btn.locked:hover {
    background: rgba(255, 255, 255, 0.03);
    color: var(--text-color);
    transform: none;
}

.stats-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
}

.stat-card strong {
    display: block;
    font-size: 1.2rem;
    margin-top: 0.45rem;
}

.flags-container {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-top: 0.45rem;
}

.flag {
    background: rgba(18, 18, 18, 0.85);
    color: var(--muted-text);
    padding: 0.35rem 0.65rem;
    font-size: 0.78rem;
    opacity: 0.55;
}

.flag.earned {
    color: var(--accent-color);
    opacity: 1;
    border: 1px solid rgba(255, 204, 0, 0.4);
}

.flag.locked-flag {
    color: var(--muted-text);
    border: 1px dashed rgba(255, 255, 255, 0.12);
}

.progress-card {
    margin-top: 1rem;
}

.progress-meter {
    width: 100%;
    height: 14px;
    border-radius: 999px;
    background: rgba(18, 18, 18, 0.95);
    overflow: hidden;
    margin: 0.8rem 0;
}

.progress-fill {
    height: 100%;
    width: 0;
    border-radius: inherit;
    background: linear-gradient(90deg, #33aaff 0%, #ffcc00 100%);
    transition: width 0.3s ease;
}

.workspace-grid {
    display: grid;
    grid-template-columns: minmax(320px, 0.95fr) minmax(360px, 1.05fr);
    gap: 1.4rem;
    align-items: stretch;
}

.lesson-panel,
.terminal-panel {
    padding: 1.3rem;
    height: 760px;
}

.terminal-panel {
    display: flex;
    flex-direction: column;
}

.tag {
    padding: 0.35rem 0.8rem;
    font-size: 0.82rem;
    font-weight: bold;
}

.level-tag {
    background: rgba(51, 170, 255, 0.16);
    color: var(--terminal-prompt);
}

.command-tag {
    background: var(--accent-soft);
    color: var(--accent-color);
}

.command-title {
    color: var(--accent-color);
    margin-bottom: 0.5rem;
}

.lesson-card.emphasis {
    background: linear-gradient(180deg, rgba(255, 204, 0, 0.12), rgba(255, 204, 0, 0.05));
}

.lesson-card p,
.hint-text,
.task-description {
    margin: 0.45rem 0 0;
}

.lesson-meta {
    margin: 1rem 0;
}

.lesson-meta .lesson-card {
    flex: 1;
    min-width: 220px;
}

.lesson-card code {
    display: block;
    margin-top: 0.5rem;
    color: var(--terminal-text);
    background: rgba(18, 18, 18, 0.9);
    padding: 0.7rem 0.85rem;
    border-radius: var(--radius-sm);
    white-space: pre-wrap;
}

.hint-box {
    margin-bottom: 1rem;
}

.feedback-panel {
    margin-bottom: 1rem;
    line-height: 1.6;
}

.feedback-panel.info {
    border-color: rgba(51, 170, 255, 0.35);
}

.feedback-panel.success {
    border-color: rgba(51, 204, 51, 0.45);
    color: #bdf7bd;
}

.feedback-panel.error {
    border-color: rgba(255, 51, 51, 0.45);
    color: #ffc1c1;
}

.terminal-tip {
    margin: 0 0 1rem;
    color: var(--muted-text);
    font-size: 0.92rem;
}

.terminal-tip code {
    color: var(--accent-color);
    background: rgba(18, 18, 18, 0.9);
    padding: 0.15rem 0.45rem;
    border-radius: 999px;
}

.terminal-container {
    background: rgba(18, 18, 18, 0.98);
    border-radius: 0 0 var(--radius-lg) var(--radius-lg);
    padding: 1.2rem;
    flex: 1;
    min-height: 0;
    display: flex;
    flex-direction: column;
}

.terminal-output {
    flex: 1;
    color: var(--terminal-text);
    white-space: pre-wrap;
    overflow-y: auto;
    overflow-x: hidden;
    line-height: 1.6;
    padding-right: 0.2rem;
    scrollbar-width: thin;
    scrollbar-color: rgba(255, 204, 0, 0.45) rgba(255, 255, 255, 0.06);
}

.terminal-output::-webkit-scrollbar {
    width: 10px;
}

.terminal-output::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 999px;
}

.terminal-output::-webkit-scrollbar-thumb {
    background: rgba(255, 204, 0, 0.38);
    border-radius: 999px;
    border: 2px solid rgba(18, 18, 18, 0.95);
}

.terminal-output::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 204, 0, 0.55);
}

.terminal-input-line {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    padding-top: 0.8rem;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}

#terminal-input,
.flag-input {
    width: 100%;
    background: transparent;
    border: none;
    outline: none;
    color: var(--terminal-text);
    font-family: "Courier New", monospace;
    font-size: 1rem;
}

.flag-input {
    border: 1px solid rgba(255, 204, 0, 0.4);
    border-radius: var(--radius-sm);
    padding: 0.8rem 0.9rem;
    background: rgba(18, 18, 18, 0.98);
    margin-top: 0.5rem;
}

button {
    font: inherit;
}

.start-btn,
.secondary-btn,
.submit-flag-btn,
.command-list-btn,
.hint-btn,
.modal-btn,
.verify-btn,
.close-btn,
.reset-btn {
    border: none;
    border-radius: 999px;
    cursor: pointer;
    transition: transform 0.2s ease, opacity 0.2s ease, background-color 0.2s ease;
}

.start-btn,
.submit-flag-btn,
.command-list-btn,
.modal-btn,
.verify-btn {
    background: var(--accent-color);
    color: var(--bg-color);
    padding: 0.75rem 1.25rem;
    font-weight: bold;
}

.secondary-btn,
.hint-btn,
.close-btn {
    background: transparent;
    color: var(--text-color);
    padding: 0.75rem 1.25rem;
    border: 1px solid rgba(255, 204, 0, 0.45);
}

.export-btn {
    background: rgba(51, 170, 255, 0.14);
    border-color: rgba(51, 170, 255, 0.45);
    color: #a8d9ff;
}

.import-btn {
    background: rgba(51, 204, 51, 0.14);
    border-color: rgba(51, 204, 51, 0.4);
    color: #bdf7bd;
}

.reset-btn {
    background: rgba(255, 51, 51, 0.16);
    color: #ffd5d5;
    padding: 0.75rem 1.1rem;
    border: 1px solid rgba(255, 51, 51, 0.35);
}

.start-btn:hover,
.secondary-btn:hover,
.submit-flag-btn:hover,
.command-list-btn:hover,
.hint-btn:hover,
.modal-btn:hover,
.verify-btn:hover,
.close-btn:hover,
.reset-btn:hover {
    transform: translateY(-2px);
}

.modal,
#flag-modal,
#reset-modal,
.level-complete-modal {
    position: fixed;
    inset: 0;
    z-index: 100;
}

.modal {
    inset: 50% auto auto 50%;
    transform: translate(-50%, -50%);
    width: min(680px, calc(100% - 2rem));
    padding: 2rem;
    border-radius: var(--radius-lg);
    z-index: 120;
}

.modal-title {
    margin-top: 0;
    color: var(--accent-color);
}

.modal-content {
    max-height: 60vh;
    overflow-y: auto;
    color: var(--text-color);
}

.instructions-list {
    padding-left: 1.2rem;
    line-height: 1.8;
}

.overlay,
.level-complete-modal {
    background: rgba(0, 0, 0, 0.72);
}

.flag-input-container {
    position: fixed;
    inset: 50% auto auto 50%;
    transform: translate(-50%, -50%);
    width: min(420px, calc(100% - 2rem));
    padding: 1.6rem;
    border-radius: var(--radius-lg);
    text-align: center;
    z-index: 130;
}

.flag-input-container h3 {
    margin-top: 0;
    color: var(--accent-color);
}

.flag-msg {
    margin-top: 1rem;
    padding: 0.85rem 0.9rem;
    border-radius: var(--radius-sm);
}

.flag-msg.success {
    background: rgba(51, 204, 51, 0.12);
    color: #bdf7bd;
}

.flag-msg.error {
    background: rgba(255, 51, 51, 0.12);
    color: #ffc1c1;
}

.command-list-grid {
    display: grid;
    gap: 1rem;
}

.command-list-card h4 {
    margin: 0 0 0.9rem;
    color: var(--accent-color);
}

.command-list-item {
    display: flex;
    justify-content: space-between;
    gap: 1rem;
    padding: 0.45rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

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

.status-ok {
    color: var(--success-color);
}

.status-pending {
    color: var(--muted-text);
}

.level-complete-modal {
    display: flex;
    align-items: center;
    justify-content: center;
}

.level-complete-card {
    width: min(520px, calc(100% - 2rem));
    padding: 2rem;
    background: rgba(42, 42, 42, 0.95);
    border: 1px solid rgba(255, 204, 0, 0.35);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    text-align: center;
}

.level-complete-card h3 {
    color: var(--accent-color);
    margin-top: 0;
}

.flag-display {
    margin: 1rem 0;
    padding: 1rem;
    border-radius: var(--radius-md);
    background: rgba(18, 18, 18, 0.95);
    color: var(--terminal-text);
    border: 1px dashed rgba(255, 204, 0, 0.45);
}

.site-footer {
    padding: 1rem;
    text-align: center;
    font-size: 0.88rem;
    border-top: 1px solid var(--border-color);
    border-bottom: none;
}

.hide {
    display: none !important;
}

@media (max-width: 1080px) {
    .intro-hero,
    .workspace-grid,
    .stats-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 760px) {
    .container {
        width: min(100%, calc(100% - 1rem));
    }

    .site-header {
        padding: 1rem 0.75rem;
    }

    .dashboard-panel,
    .lesson-panel,
    .terminal-panel,
    .intro-copy {
        padding: 1rem;
    }

    .intro-steps {
        grid-template-columns: 1fr;
    }

    .dashboard-actions,
    .intro-actions,
    .flag-btns,
    .lesson-meta {
        flex-direction: column;
    }

    .dashboard-actions > button,
    .intro-actions > button,
    .flag-btns > button {
        width: 100%;
    }

    .terminal-container {
        height: 420px;
        min-height: 420px;
    }

    .lesson-panel,
    .terminal-panel {
        height: auto;
    }
}