/* Python Pro - Olio-ohjelmointi & Edistynyt Python */
/* Based on Metamatic Koodikoulu theme, with purple Pro accent */

:root {
    --bg: #0f0e17;
    --surface: #1a1a2e;
    --surface2: #16213e;
    --primary: #b388ff;
    --primary-glow: rgba(179, 136, 255, 0.25);
    --green: #00d26a;
    --green-glow: rgba(0, 210, 106, 0.2);
    --red: #ff6b6b;
    --blue: #4fc3f7;
    --purple: #b388ff;
    --gold: #e2b714;
    --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;
    padding-bottom: 44px;
}

h1, h2, h3 { font-family: 'Fredoka One', cursive; }

.hidden { display: none !important; }

/* Loading Screen */
#loading-screen {
    position: fixed; inset: 0; z-index: 1000;
    background: var(--bg);
    display: flex; align-items: center; justify-content: center;
}

.loading-content { text-align: center; }

.loading-snake {
    font-size: 60px;
    animation: bounce 1s infinite alternate;
}

@keyframes bounce {
    from { transform: translateY(0); }
    to { transform: translateY(-15px); }
}

.loading-content h1 {
    font-size: 2rem; margin: 16px 0 8px;
    background: linear-gradient(135deg, var(--primary), var(--blue));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}

.loading-content p { color: var(--text-dim); margin-bottom: 24px; }

.loading-bar {
    width: 300px; height: 6px; background: var(--surface);
    border-radius: 3px; margin: 0 auto; overflow: hidden;
}

.loading-bar-fill {
    width: 30%; height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--blue));
    border-radius: 3px;
    animation: load 1.5s ease-in-out infinite;
}

@keyframes load {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(400%); }
}

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

/* Sidebar */
#sidebar {
    width: var(--sidebar-w); background: var(--surface);
    padding: 20px 16px; position: sticky; top: 0; height: 100vh;
    overflow-y: auto; display: flex; flex-direction: column;
    border-right: 1px solid rgba(179, 136, 255, 0.1);
}

.sidebar-header { text-align: center; margin-bottom: 16px; }

.sidebar-header h1 {
    font-size: 1.3rem;
    background: linear-gradient(135deg, var(--primary), var(--blue));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}

.sidebar-header .subtitle {
    font-size: 0.8rem; color: var(--text-dim); margin-top: 4px;
}

.logo-icon {
    width: 24px; height: 24px; vertical-align: middle;
    margin-right: 4px; border-radius: 4px;
}

.progress-section { margin-bottom: 12px; }

.progress-bar {
    height: 6px; background: var(--surface2); border-radius: 3px;
    overflow: hidden; margin-bottom: 4px;
}

#progress-fill {
    height: 100%; width: 0%;
    background: linear-gradient(90deg, var(--primary), var(--green));
    border-radius: 3px; transition: width 0.5s ease;
}

#progress-text { font-size: 0.75rem; color: var(--text-dim); }

#lesson-list {
    list-style: none; flex: 1; overflow-y: auto;
    margin-bottom: 12px;
}

#lesson-list li {
    display: flex; align-items: center; gap: 8px;
    padding: 10px 12px; border-radius: 8px;
    cursor: pointer; transition: background 0.2s;
    margin-bottom: 2px;
}

#lesson-list li:hover { background: var(--surface2); }
#lesson-list li.active { background: var(--primary-glow); border: 1px solid var(--primary); }
#lesson-list li.completed .lesson-num { background: var(--green); }

.lesson-num {
    width: 28px; height: 28px; border-radius: 50%;
    background: var(--surface2); display: flex;
    align-items: center; justify-content: center;
    font-size: 0.75rem; font-weight: 700; flex-shrink: 0;
}

.lesson-name {
    flex: 1; font-size: 0.85rem; font-weight: 600;
    white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}

.lesson-stars { font-size: 0.7rem; color: var(--gold); }

.section-divider {
    padding: 12px 12px 6px; cursor: default;
    border-bottom: 1px solid var(--primary-glow);
    margin-top: 8px; margin-bottom: 4px;
}

.section-divider:hover { background: transparent; }

.section-label {
    font-size: 0.75rem; font-weight: 800;
    text-transform: uppercase; letter-spacing: 1px;
    color: var(--primary);
}

.sidebar-footer { text-align: center; padding-top: 8px; border-top: 1px solid var(--surface2); }

.stars-earned {
    font-size: 0.85rem; font-weight: 700; color: var(--gold);
}

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

/* Welcome Screen */
.welcome-hero { text-align: center; padding: 60px 20px; }
.welcome-emoji { font-size: 100px; margin-bottom: 20px; }

.welcome-hero h1 {
    font-size: 2.5rem; margin-bottom: 16px;
    background: linear-gradient(135deg, 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: 600px; margin: 0 auto 32px; line-height: 1.6; }

.welcome-features {
    display: grid; grid-template-columns: 1fr 1fr;
    gap: 16px; max-width: 400px; margin: 0 auto 32px;
}

.feature {
    background: var(--surface); border-radius: var(--radius);
    padding: 16px; display: flex; align-items: center; gap: 10px;
    font-weight: 600;
}

.feature-icon { font-size: 1.5rem; }

.btn-start {
    background: linear-gradient(135deg, var(--primary), #9c64ff);
    color: white; border: none; padding: 16px 32px;
    font-size: 1.1rem; font-weight: 800; border-radius: 50px;
    cursor: pointer; font-family: 'Nunito', sans-serif;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-start:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px var(--primary-glow);
}

.back-link { margin-top: 20px; }
.back-link a { color: var(--text-dim); text-decoration: none; font-size: 0.9rem; }
.back-link a:hover { color: var(--primary); }

/* Lesson View */
.lesson-header { margin-bottom: 24px; }

#lesson-badge {
    display: inline-block; background: var(--primary-glow);
    color: var(--primary); padding: 4px 12px; border-radius: 20px;
    font-size: 0.8rem; font-weight: 700; margin-bottom: 8px;
}

#lesson-title { font-size: 1.8rem; margin-bottom: 8px; }
#lesson-description { color: var(--text-dim); font-size: 1rem; }

/* Theory */
#theory-section {
    background: var(--surface); border-radius: var(--radius);
    padding: 24px; margin-bottom: 24px;
    border-left: 4px solid var(--blue);
    line-height: 1.7;
}

#theory-section h3 { color: var(--blue); margin-bottom: 12px; }
#theory-section p { margin-bottom: 12px; }
#theory-section ul, #theory-section ol { margin: 12px 0 12px 24px; }
#theory-section li { margin-bottom: 6px; }

#theory-section code {
    background: var(--code-bg); color: var(--primary);
    padding: 2px 6px; border-radius: 4px; font-size: 0.9rem;
}

#theory-section pre {
    background: var(--code-bg); padding: 16px;
    border-radius: 8px; overflow-x: auto; margin: 12px 0;
}

#theory-section pre code {
    background: none; padding: 0; color: var(--green);
}

/* Challenge */
.challenge-section h3 { color: var(--primary); margin-bottom: 12px; }
#challenge-text { color: var(--text-dim); margin-bottom: 16px; line-height: 1.6; }
#challenge-text code {
    background: var(--code-bg); color: var(--primary);
    padding: 2px 6px; border-radius: 4px;
}

/* Editor */
.editor-container {
    border-radius: var(--radius); overflow: hidden;
    border: 1px solid var(--surface2); margin-bottom: 16px;
}

.editor-toolbar {
    display: flex; justify-content: space-between; align-items: center;
    padding: 8px 12px; background: var(--surface);
}

.editor-title { font-size: 0.85rem; color: var(--text-dim); }

.editor-buttons { display: flex; gap: 6px; }

.editor-buttons button {
    background: var(--surface2); color: var(--text);
    border: none; padding: 6px 12px; border-radius: 6px;
    font-size: 0.8rem; cursor: pointer; font-family: 'Nunito', sans-serif;
    font-weight: 600; transition: background 0.2s;
}

.editor-buttons button:hover { background: var(--primary-glow); }

.btn-run {
    background: var(--primary) !important; color: var(--bg) !important;
}

#code-editor {
    width: 100%; min-height: 280px; padding: 16px;
    background: var(--code-bg); color: var(--green);
    border: none; outline: none; resize: vertical;
    font-family: 'Courier New', monospace; font-size: 15px;
    line-height: 1.5; tab-size: 4;
}

/* Hint */
.hint-box, #hint-box {
    background: var(--primary-glow); border: 1px solid var(--primary);
    border-radius: var(--radius); padding: 16px; margin-bottom: 16px;
    color: var(--text);
}

/* Output */
.output-container {
    border-radius: var(--radius); overflow: hidden;
    border: 1px solid var(--surface2); margin-bottom: 16px;
}

.output-toolbar {
    padding: 8px 12px; background: var(--surface);
    font-size: 0.85rem; color: var(--text-dim);
}

#output-area {
    padding: 16px; background: var(--code-bg);
    color: var(--green); font-family: 'Courier New', monospace;
    font-size: 14px; min-height: 60px; white-space: pre-wrap;
}

/* Result */
.result-box, #result-box {
    border-radius: var(--radius); padding: 16px;
    margin-bottom: 16px; font-weight: 700; text-align: center;
}

#result-box.success {
    background: var(--green-glow); border: 1px solid var(--green);
    color: var(--green);
}

#result-box.fail {
    background: rgba(255, 107, 107, 0.15); border: 1px solid var(--red);
    color: var(--red);
}

/* Navigation */
.lesson-nav {
    display: flex; justify-content: space-between; margin-top: 20px;
}

.lesson-nav button {
    background: var(--surface); color: var(--text);
    border: 1px solid var(--surface2); padding: 10px 20px;
    border-radius: 8px; font-size: 0.9rem; cursor: pointer;
    font-family: 'Nunito', sans-serif; font-weight: 700;
    transition: background 0.2s;
}

.lesson-nav button:hover { background: var(--surface2); }

#btn-next {
    background: var(--primary); color: var(--bg);
    border-color: var(--primary);
}

#btn-next:hover { opacity: 0.9; }

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

/* Footer */
#site-footer {
    position: fixed; bottom: 0; left: 0; right: 0;
    background: var(--surface); padding: 10px 0;
    text-align: center; z-index: 40;
    border-top: 1px solid var(--surface2);
}

.footer-content {
    display: flex; align-items: center; justify-content: center;
    gap: 12px; font-size: 0.8rem; color: var(--text-dim);
}

.footer-brand {
    font-family: 'Fredoka One', cursive; color: var(--primary);
    display: flex; align-items: center; gap: 6px;
}

.footer-separator { color: var(--surface2); }

.footer-company a { color: var(--blue); text-decoration: none; }
.footer-company a:hover { text-decoration: underline; }

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

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

    .sidebar-header h1 { font-size: 1rem; }
    .sidebar-header .subtitle { display: none; }
    .progress-section { margin-bottom: 8px; }

    #lesson-list {
        display: flex; overflow-x: auto; gap: 4px;
        padding-bottom: 4px;
    }

    #lesson-list li {
        flex-shrink: 0; padding: 6px 10px;
    }

    .lesson-name, .lesson-stars { display: none; }

    .section-divider {
        flex-shrink: 0; padding: 6px 8px;
        border-bottom: none; border-right: 1px solid var(--primary-glow);
        margin: 0;
    }

    .section-label { font-size: 0.65rem; white-space: nowrap; }

    .sidebar-footer { display: none; }

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

    .welcome-hero { padding: 30px 10px; }
    .welcome-hero h1 { font-size: 1.8rem; }
    .welcome-emoji { font-size: 70px; }
    .welcome-features { grid-template-columns: 1fr; }

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

    #site-footer { position: static; margin-top: 20px; }
    body { padding-bottom: 0; }
}