/* ========================================
   METAMATIC KOODIKOULU - Styles
   ======================================== */

:root {
    --bg: #0f0e17;
    --surface: #1a1a2e;
    --surface2: #16213e;
    --primary: #e2b714;
    --primary-glow: #e2b71444;
    --green: #00d26a;
    --green-glow: #00d26a33;
    --red: #ff6b6b;
    --blue: #4fc3f7;
    --purple: #b388ff;
    --text: #fffffe;
    --text-dim: #a7a9be;
    --code-bg: #0d1117;
    --radius: 12px;
    --sidebar-w: 280px;
}

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

body {
    font-family: 'Nunito', sans-serif;
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    overflow-x: hidden;
}

h1, h2, h3 { font-family: 'Fredoka One', cursive; }
.hidden { display: none !important; }

/* ── Loading Screen ── */
#loading-screen {
    position: fixed; inset: 0;
    background: var(--bg);
    display: flex; align-items: center; justify-content: center;
    z-index: 1000;
}
.loading-content { text-align: center; }
.loading-snake {
    font-size: 80px;
    animation: bounce 1s ease infinite;
}
@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
}
.loading-content h1 {
    font-size: 2rem; margin: 20px 0 10px;
    background: linear-gradient(90deg, var(--primary), var(--blue));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.loading-content p { color: var(--text-dim); }
.loading-bar {
    width: 300px; height: 8px; background: var(--surface);
    border-radius: 4px; margin: 20px auto; overflow: hidden;
}
.loading-bar-fill {
    width: 0%; height: 100%; background: var(--primary);
    border-radius: 4px; animation: load 3s ease-in-out forwards;
}
@keyframes load { to { width: 100%; } }

/* ── App Layout ── */
#app {
    display: flex; min-height: 100vh;
}

/* ── Sidebar ── */
#sidebar {
    width: var(--sidebar-w); min-width: var(--sidebar-w);
    background: var(--surface);
    padding: 24px 16px;
    display: flex; flex-direction: column;
    border-right: 1px solid #ffffff10;
    position: sticky; top: 0; height: 100vh;
    overflow-y: auto;
}
.sidebar-header h1 {
    font-size: 1.3rem;
    background: linear-gradient(90deg, var(--primary), var(--blue));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.sidebar-header .subtitle {
    color: var(--text-dim); font-size: 0.85rem; margin-top: 2px;
}
.progress-section { margin: 20px 0; }
.progress-bar {
    height: 10px; background: var(--bg); border-radius: 5px;
    overflow: hidden;
}
.progress-fill {
    height: 100%; width: 0%;
    background: linear-gradient(90deg, var(--green), var(--blue));
    border-radius: 5px; transition: width 0.5s ease;
}
.progress-text {
    font-size: 0.8rem; color: var(--text-dim); margin-top: 6px;
    display: block; text-align: right;
}
#lesson-list {
    list-style: none; flex: 1; overflow-y: auto;
}
#lesson-list li {
    padding: 10px 12px; margin: 4px 0;
    border-radius: 8px; cursor: pointer;
    display: flex; align-items: center; gap: 10px;
    font-size: 0.9rem; transition: all 0.2s;
    color: var(--text-dim);
}
#lesson-list li:hover { background: var(--bg); color: var(--text); }
#lesson-list li.active { background: var(--primary-glow); color: var(--primary); font-weight: 700; }
#lesson-list li.completed { color: var(--green); }
#lesson-list li .lesson-num {
    width: 28px; height: 28px; border-radius: 50%;
    background: var(--bg); display: flex; align-items: center;
    justify-content: center; font-size: 0.8rem; font-weight: 700;
    flex-shrink: 0;
}
#lesson-list li.active .lesson-num { background: var(--primary); color: var(--bg); }
#lesson-list li.completed .lesson-num { background: var(--green); color: var(--bg); }
#lesson-list li .lesson-stars { margin-left: auto; font-size: 0.75rem; }

/* ── Logo Icon ── */
.logo-icon {
    width: 24px;
    height: 24px;
    vertical-align: middle;
    margin-right: 4px;
}

/* ── Section Divider (Ekspertti) ── */
#lesson-list li.section-divider {
    padding: 12px 16px 6px;
    cursor: default;
    border-bottom: 1px solid var(--primary-glow);
    margin-top: 8px;
}
#lesson-list li.section-divider:hover { background: transparent; }
.section-label {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--primary);
}

.sidebar-footer {
    padding-top: 16px; border-top: 1px solid #ffffff10;
    margin-top: 16px;
}
.stars-earned {
    text-align: center; font-size: 1rem;
    color: var(--primary);
}

/* ── Main Content ── */
#main-content {
    flex: 1; padding: 40px;
    max-width: 900px; margin: 0 auto;
}

/* ── Welcome Screen ── */
.welcome-hero { text-align: center; padding: 60px 0; }
.welcome-emoji { font-size: 100px; margin-bottom: 20px; }
.welcome-hero h1 {
    font-size: 2.5rem; margin-bottom: 16px;
    background: linear-gradient(90deg, var(--primary), var(--green));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.welcome-hero > p { color: var(--text-dim); font-size: 1.1rem; max-width: 500px; margin: 0 auto 30px; }
.welcome-features {
    display: grid; grid-template-columns: 1fr 1fr;
    gap: 16px; max-width: 400px; margin: 0 auto 40px;
}
.feature {
    background: var(--surface); padding: 16px; border-radius: var(--radius);
    display: flex; align-items: center; gap: 12px;
}
.feature-icon { font-size: 1.5rem; }
.btn-start {
    background: linear-gradient(135deg, var(--primary), #f0c040);
    color: var(--bg); border: none; padding: 16px 40px;
    font-family: 'Fredoka One', cursive; font-size: 1.3rem;
    border-radius: 50px; cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    box-shadow: 0 4px 20px var(--primary-glow);
}
.btn-start:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px var(--primary-glow);
}

/* ── Lesson View ── */
.lesson-header {
    margin-bottom: 30px;
}
.lesson-badge {
    display: inline-block; background: var(--primary);
    color: var(--bg); padding: 4px 14px; border-radius: 20px;
    font-size: 0.8rem; font-weight: 700; margin-bottom: 10px;
}
.lesson-header h2 { font-size: 1.8rem; margin-bottom: 8px; }
.lesson-desc { color: var(--text-dim); font-size: 1rem; line-height: 1.6; }

/* ── Theory ── */
.theory-section {
    background: var(--surface); padding: 24px;
    border-radius: var(--radius); margin-bottom: 30px;
    border-left: 4px solid var(--blue);
    line-height: 1.8;
}
.theory-section h4 {
    color: var(--blue); margin-bottom: 12px; font-size: 1.1rem;
}
.theory-section p { margin-bottom: 12px; }
.theory-section code {
    background: var(--code-bg); padding: 2px 8px;
    border-radius: 4px; font-family: 'Courier New', monospace;
    color: var(--primary); font-size: 0.9rem;
}
.theory-section pre {
    background: var(--code-bg); padding: 16px;
    border-radius: 8px; margin: 12px 0;
    overflow-x: auto; font-size: 0.9rem;
}
.theory-section pre code {
    background: none; padding: 0; color: var(--text);
}

/* ── Challenge ── */
.challenge-section h3 {
    font-size: 1.3rem; margin-bottom: 10px;
}
#challenge-text {
    color: var(--text-dim); margin-bottom: 20px;
    line-height: 1.6; font-size: 1rem;
}

/* ── Editor ── */
.editor-container {
    border-radius: var(--radius); overflow: hidden;
    border: 1px solid #ffffff15; margin-bottom: 16px;
}
.editor-toolbar {
    background: var(--surface2); padding: 10px 16px;
    display: flex; justify-content: space-between;
    align-items: center;
}
.editor-title { font-size: 0.85rem; color: var(--text-dim); }
.editor-buttons { display: flex; gap: 8px; }
.editor-buttons button {
    border: none; padding: 6px 14px; border-radius: 6px;
    font-family: 'Nunito', sans-serif; font-size: 0.85rem;
    cursor: pointer; font-weight: 600; transition: all 0.2s;
}
.btn-run {
    background: var(--green); color: var(--bg);
}
.btn-run:hover { filter: brightness(1.1); transform: translateY(-1px); }
.btn-reset { background: var(--surface); color: var(--text-dim); }
.btn-hint { background: var(--primary-glow); color: var(--primary); }

#code-editor {
    width: 100%; min-height: 280px; padding: 16px;
    background: var(--code-bg); color: var(--text);
    border: none; resize: vertical;
    font-family: 'Courier New', monospace;
    font-size: 15px; line-height: 1.6;
    tab-size: 4;
}
#code-editor:focus { outline: none; }

/* ── Hint ── */
.hint-box {
    background: var(--primary-glow); border: 1px solid var(--primary);
    padding: 14px 18px; border-radius: var(--radius);
    margin-bottom: 16px;
    animation: fadeIn 0.3s ease;
}
.hint-box p { color: var(--primary); font-size: 0.95rem; }

/* ── Output ── */
.output-container {
    border-radius: var(--radius); overflow: hidden;
    border: 1px solid #ffffff15; margin-bottom: 20px;
}
.output-toolbar {
    background: var(--surface2); padding: 8px 16px;
    font-size: 0.85rem; color: var(--text-dim);
}
#output-area {
    background: var(--code-bg); padding: 16px;
    font-family: 'Courier New', monospace;
    font-size: 14px; min-height: 60px;
    color: var(--green); white-space: pre-wrap;
    word-break: break-word;
}

/* ── Result Box ── */
.result-box {
    padding: 20px; border-radius: var(--radius);
    text-align: center; font-weight: 700;
    font-size: 1.1rem; margin-bottom: 20px;
    animation: fadeIn 0.5s ease;
}
.result-box.success {
    background: var(--green-glow); border: 2px solid var(--green);
    color: var(--green);
}
.result-box.fail {
    background: #ff6b6b22; border: 2px solid var(--red);
    color: var(--red);
}
.result-stars { font-size: 2rem; display: block; margin-top: 8px; }

/* ── Navigation ── */
.lesson-nav {
    display: flex; justify-content: space-between;
    margin-top: 30px;
}
.btn-prev, .btn-next {
    background: var(--surface); color: var(--text);
    border: 1px solid #ffffff15; padding: 12px 24px;
    border-radius: 8px; font-family: 'Nunito', sans-serif;
    font-size: 1rem; font-weight: 600;
    cursor: pointer; transition: all 0.2s;
}
.btn-prev:hover, .btn-next:hover {
    background: var(--surface2); transform: translateY(-2px);
}
.btn-next {
    background: var(--primary); color: var(--bg); border-color: var(--primary);
}

/* ── Confetti ── */
#confetti-canvas {
    position: fixed; inset: 0;
    pointer-events: none; z-index: 9999;
}

/* ── Animations ── */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ── Responsive ── */
@media (max-width: 768px) {
    #app { flex-direction: column; }

    #sidebar {
        width: 100%; min-width: 100%;
        height: auto; position: sticky; top: 0;
        flex-direction: column;
        padding: 12px 16px;
        z-index: 50;
    }

    .sidebar-header {
        display: flex; align-items: center;
        justify-content: space-between;
    }
    .sidebar-header h1 { font-size: 1.1rem; }
    .sidebar-header .subtitle { display: none; }

    .progress-section { margin: 8px 0; }

    #lesson-list {
        display: flex;
        flex-wrap: nowrap;
        gap: 6px;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        padding: 4px 0;
    }
    #lesson-list::-webkit-scrollbar { display: none; }

    #lesson-list li {
        padding: 6px;
        margin: 0;
        min-width: 40px;
        justify-content: center;
        flex-shrink: 0;
    }
    /* Hide lesson text on mobile, show only number circle */
    #lesson-list li .lesson-name { display: none; }
    #lesson-list li .lesson-stars { display: none; }

    /* Section divider: compact on mobile */
    #lesson-list li.section-divider {
        padding: 4px 8px 2px;
        margin-top: 4px;
        min-width: auto;
    }
    #lesson-list li.section-divider .section-label {
        font-size: 0.6rem;
        letter-spacing: 0.5px;
    }

    .sidebar-footer { display: none; }

    #main-content {
        padding: 16px;
        padding-bottom: 80px;
    }

    .welcome-hero { padding: 30px 0; }
    .welcome-emoji { font-size: 70px; }
    .welcome-hero h1 { font-size: 1.8rem; }
    .welcome-hero > p { font-size: 0.95rem; }
    .welcome-features { grid-template-columns: 1fr; }

    .lesson-header h2 { font-size: 1.4rem; }

    #code-editor {
        font-size: 13px;
        min-height: 220px;
    }

    .theory-section { padding: 16px; }
    .theory-section pre { font-size: 0.8rem; }

    .btn-start {
        font-size: 1.1rem;
        padding: 14px 32px;
    }

    /* Footer: make it static on mobile so it doesn't overlap content */
    #site-footer {
        position: static !important;
        margin-top: 20px;
    }
    body { padding-bottom: 0 !important; }
}

/* ── Footer ── */
#site-footer {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: #1a1a2e;
    border-top: 1px solid #333;
    padding: 10px 20px;
    z-index: 100;
    text-align: center;
    font-size: 0.8rem;
    color: #aaa;
}

.footer-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    flex-wrap: wrap;
}

.footer-brand {
    font-family: 'Fredoka One', cursive;
    color: #e2b714;
    font-size: 0.85rem;
}

.footer-separator {
    color: #555;
}

.footer-company a {
    color: #4fc3f7;
    text-decoration: none;
}

.footer-company a:hover {
    text-decoration: underline;
}

/* Give body bottom padding so content isn't hidden behind fixed footer */
body {
    padding-bottom: 44px;
}