/* ==========================================================================
   PyLantern — Python teaching platform styles
   Hand-written CSS using custom properties, matching the project's framework-
   free approach (no Bootstrap/Tailwind). Dark, modern "code editor" aesthetic
   with a warm amber "lantern" accent.
   ========================================================================== */

:root {
    --pl-bg: #0b1020;
    --pl-bg-2: #111936;
    --pl-surface: #16203f;
    --pl-surface-2: #1d2a52;
    --pl-border: rgba(148, 163, 184, 0.18);
    --pl-text: #e8eefc;
    --pl-muted: #9fb0d0;
    --pl-primary: #ffb020;      /* lantern amber */
    --pl-primary-2: #ff8a00;
    --pl-accent: #4f8cff;       /* python blue */
    --pl-accent-2: #22c55e;     /* success green */
    --pl-danger: #ef4444;
    --pl-radius: 16px;
    --pl-shadow: 0 18px 50px rgba(2, 6, 23, 0.55);
    --pl-font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --pl-mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', Consolas, monospace;
}

* { box-sizing: border-box; }

body.pl {
    margin: 0;
    font-family: var(--pl-font);
    color: var(--pl-text);
    background:
        radial-gradient(1100px 500px at 85% -5%, rgba(255, 176, 32, 0.12), transparent 60%),
        radial-gradient(900px 500px at 0% 10%, rgba(79, 140, 255, 0.12), transparent 55%),
        var(--pl-bg);
    min-height: 100vh;
    line-height: 1.6;
}

a { color: inherit; text-decoration: none; }
.pl-container { width: 100%; max-width: 1140px; margin: 0 auto; padding: 0 20px; }

/* ---------- Nav ---------- */
.pl-nav {
    position: sticky; top: 0; z-index: 50;
    backdrop-filter: blur(10px);
    background: rgba(11, 16, 32, 0.78);
    border-bottom: 1px solid var(--pl-border);
}
.pl-nav .pl-container {
    display: flex; align-items: center; gap: 18px;
    height: 68px;
}
.pl-brand { display: flex; align-items: center; gap: 11px; font-weight: 800; font-size: 1.15rem; letter-spacing: -0.02em; }
.pl-brand svg { display: block; }
.pl-brand .pl-brand-name span { color: var(--pl-primary); }
.pl-nav-links { margin-left: auto; display: flex; align-items: center; gap: 6px; flex-wrap: wrap; }
.pl-nav-links a { padding: 8px 13px; border-radius: 10px; color: var(--pl-muted); font-weight: 500; font-size: 0.95rem; transition: all .15s; }
.pl-nav-links a:hover { color: var(--pl-text); background: var(--pl-surface); }

/* ---------- Buttons ---------- */
.pl-btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px;
    padding: 12px 22px; border-radius: 12px; font-weight: 700; font-size: 0.98rem;
    border: 1px solid transparent; cursor: pointer; transition: transform .12s, box-shadow .2s, background .2s;
}
.pl-btn:active { transform: translateY(1px); }
.pl-btn-primary {
    color: #1a1304;
    background: linear-gradient(135deg, var(--pl-primary), var(--pl-primary-2));
    box-shadow: 0 10px 28px rgba(255, 138, 0, 0.35);
}
.pl-btn-primary:hover { box-shadow: 0 14px 34px rgba(255, 138, 0, 0.5); }
.pl-btn-ghost { color: var(--pl-text); background: var(--pl-surface); border-color: var(--pl-border); }
.pl-btn-ghost:hover { background: var(--pl-surface-2); }
.pl-btn-accent { color: #fff; background: linear-gradient(135deg, var(--pl-accent), #2563eb); }
.pl-btn-block { width: 100%; }
.pl-btn-lg { padding: 15px 30px; font-size: 1.05rem; }

/* ---------- Hero ---------- */
.pl-hero { padding: 72px 0 40px; }
.pl-hero-grid { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 48px; align-items: center; }
.pl-eyebrow {
    display: inline-flex; align-items: center; gap: 8px;
    font-size: 0.82rem; font-weight: 700; letter-spacing: 0.04em; text-transform: uppercase;
    color: var(--pl-primary); background: rgba(255, 176, 32, 0.1);
    padding: 6px 14px; border-radius: 999px; border: 1px solid rgba(255, 176, 32, 0.25);
}
.pl-hero h1 { font-size: 3.1rem; line-height: 1.08; margin: 18px 0 14px; letter-spacing: -0.03em; }
.pl-hero h1 .hl { background: linear-gradient(120deg, var(--pl-primary), var(--pl-accent)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.pl-hero p.lead { font-size: 1.18rem; color: var(--pl-muted); max-width: 540px; }
.pl-hero-cta { display: flex; gap: 14px; margin-top: 28px; flex-wrap: wrap; }
.pl-hero-stats { display: flex; gap: 30px; margin-top: 34px; }
.pl-hero-stats b { display: block; font-size: 1.5rem; }
.pl-hero-stats span { color: var(--pl-muted); font-size: 0.9rem; }

/* code card */
.pl-codecard {
    background: #0d1430; border: 1px solid var(--pl-border); border-radius: var(--pl-radius);
    box-shadow: var(--pl-shadow); overflow: hidden;
}
.pl-codecard-bar { display: flex; align-items: center; gap: 7px; padding: 12px 15px; background: #0a1026; border-bottom: 1px solid var(--pl-border); }
.pl-dot { width: 11px; height: 11px; border-radius: 50%; }
.pl-codecard-bar .pl-file { margin-left: 10px; font-family: var(--pl-mono); font-size: 0.82rem; color: var(--pl-muted); }
.pl-codecard pre { margin: 0; padding: 20px; font-family: var(--pl-mono); font-size: 0.9rem; line-height: 1.7; overflow-x: auto; }
.c-kw { color: #ff8ab3; } .c-fn { color: #5ad7ff; } .c-str { color: #ffd479; } .c-com { color: #6b7aa0; } .c-num { color: #c3a6ff; }

/* ---------- Sections ---------- */
.pl-section { padding: 56px 0; }
.pl-section-head { text-align: center; max-width: 680px; margin: 0 auto 38px; }
.pl-section-head h2 { font-size: 2.1rem; letter-spacing: -0.02em; margin: 0 0 10px; }
.pl-section-head p { color: var(--pl-muted); font-size: 1.05rem; margin: 0; }

/* ---------- Cards grid ---------- */
.pl-grid { display: grid; gap: 22px; }
.pl-grid-3 { grid-template-columns: repeat(3, 1fr); }
.pl-grid-2 { grid-template-columns: repeat(2, 1fr); }
.pl-card {
    background: var(--pl-surface); border: 1px solid var(--pl-border);
    border-radius: var(--pl-radius); padding: 24px; transition: transform .18s, border-color .18s;
}
.pl-card:hover { transform: translateY(-4px); border-color: rgba(255, 176, 32, 0.4); }
.pl-card h3 { margin: 12px 0 8px; font-size: 1.2rem; }
.pl-card p { color: var(--pl-muted); margin: 0 0 14px; font-size: 0.96rem; }
.pl-ico { width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center; font-size: 1.4rem; background: rgba(79, 140, 255, 0.14); }

/* badges */
.pl-badge { display: inline-block; font-size: 0.72rem; font-weight: 700; letter-spacing: 0.03em; text-transform: uppercase; padding: 4px 10px; border-radius: 999px; }
.pl-badge.beginner { background: rgba(34, 197, 94, 0.16); color: #4ade80; }
.pl-badge.intermediate { background: rgba(79, 140, 255, 0.16); color: #7aa8ff; }
.pl-badge.advanced { background: rgba(255, 138, 0, 0.16); color: var(--pl-primary); }
.pl-badge.free { background: rgba(34, 197, 94, 0.16); color: #4ade80; }
.pl-badge.live { background: rgba(239, 68, 68, 0.16); color: #fca5a5; }

/* price */
.pl-price { font-size: 1.9rem; font-weight: 800; }
.pl-price small { font-size: 0.9rem; font-weight: 500; color: var(--pl-muted); }

/* ---------- Course card ---------- */
.pl-course-card { display: flex; flex-direction: column; }
.pl-course-card .meta { display: flex; gap: 14px; color: var(--pl-muted); font-size: 0.85rem; margin: 10px 0; }
.pl-course-card .foot { margin-top: auto; display: flex; align-items: center; justify-content: space-between; padding-top: 16px; }

/* ---------- Study plan ---------- */
.pl-module { background: var(--pl-surface); border: 1px solid var(--pl-border); border-radius: var(--pl-radius); margin-bottom: 16px; overflow: hidden; }
.pl-module-head { display: flex; align-items: center; gap: 12px; padding: 18px 22px; background: var(--pl-surface-2); }
.pl-module-head h3 { margin: 0; font-size: 1.1rem; }
.pl-module-head .step { width: 34px; height: 34px; border-radius: 10px; display: grid; place-items: center; background: linear-gradient(135deg, var(--pl-primary), var(--pl-primary-2)); color: #1a1304; font-weight: 800; }
.pl-lesson { display: flex; align-items: flex-start; gap: 12px; padding: 14px 22px; border-top: 1px solid var(--pl-border); }
.pl-lesson:hover { background: rgba(255, 255, 255, 0.02); }
.pl-lesson .tick { color: var(--pl-accent-2); font-size: 1.05rem; margin-top: 2px; }
.pl-lesson .l-title { font-weight: 600; }
.pl-lesson .l-obj { color: var(--pl-muted); font-size: 0.9rem; }
.pl-lesson .l-time { margin-left: auto; color: var(--pl-muted); font-size: 0.82rem; white-space: nowrap; }

/* ---------- Progress bar ---------- */
.pl-progress { height: 10px; background: var(--pl-surface-2); border-radius: 999px; overflow: hidden; }
.pl-progress > span { display: block; height: 100%; background: linear-gradient(90deg, var(--pl-accent-2), #16a34a); border-radius: 999px; }

/* ---------- Live room / terminal ---------- */
.pl-room-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.pl-frame-wrap { border: 1px solid var(--pl-border); border-radius: var(--pl-radius); overflow: hidden; background: #0d1430; }
.pl-frame-wrap .bar { padding: 11px 16px; background: #0a1026; border-bottom: 1px solid var(--pl-border); font-weight: 600; font-size: 0.92rem; display: flex; align-items: center; gap: 8px; }
.pl-frame-wrap iframe { width: 100%; border: 0; display: block; background: #fff; }

/* ---------- Messages ---------- */
.pl-msg { padding: 13px 18px; border-radius: 12px; margin-bottom: 14px; font-weight: 500; }
.pl-msg.success { background: rgba(34, 197, 94, 0.14); color: #86efac; border: 1px solid rgba(34, 197, 94, 0.3); }
.pl-msg.error { background: rgba(239, 68, 68, 0.14); color: #fca5a5; border: 1px solid rgba(239, 68, 68, 0.3); }
.pl-msg.info { background: rgba(79, 140, 255, 0.14); color: #bfd4ff; border: 1px solid rgba(79, 140, 255, 0.3); }

/* ---------- Footer ---------- */
.pl-footer { border-top: 1px solid var(--pl-border); margin-top: 40px; padding: 30px 0; color: var(--pl-muted); font-size: 0.9rem; }
.pl-footer .pl-container { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; align-items: center; }
.pl-footer a:hover { color: var(--pl-text); }

/* ---------- Empty state ---------- */
.pl-empty { text-align: center; padding: 50px 20px; color: var(--pl-muted); }

/* ---------- Responsive ---------- */
@media (max-width: 880px) {
    .pl-hero-grid { grid-template-columns: 1fr; }
    .pl-grid-3 { grid-template-columns: 1fr; }
    .pl-grid-2 { grid-template-columns: 1fr; }
    .pl-room-grid { grid-template-columns: 1fr; }
    .pl-hero h1 { font-size: 2.3rem; }
    .pl-nav-links a { padding: 7px 9px; font-size: 0.88rem; }
}