/* ═══════════════════════════════════════
   DESIGN TOKENS
   ═══════════════════════════════════════ */
:root {
    --white: #ffffff;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    --gray-950: #030712;

    --blue-50: #eff6ff;
    --blue-100: #dbeafe;
    --blue-600: #2563eb;
    --blue-700: #1d4ed8;
    --blue-800: #1e40af;

    --amber-100: #fef3c7;
    --amber-600: #d97706;
    --amber-800: #92400e;

    --green-500: #22c55e;
    --red-400: #f87171;

    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
    --shadow-lg: 0 8px 30px rgba(0,0,0,0.08);
    --shadow-xl: 0 20px 60px rgba(0,0,0,0.1);
    --transition: 0.25s ease;
}

/* ═══════════════════════════════════════
   RESET & BASE
   ═══════════════════════════════════════ */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; scrollbar-width: thin; scrollbar-color: var(--gray-300) transparent; }
body {
    font-family: var(--font);
    color: var(--gray-800);
    background: var(--white);
    line-height: 1.65;
    overflow-x: hidden;
}

/* Custom Scrollbar */
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--gray-300); border-radius: 10px; }
::-webkit-scrollbar-thumb:hover { background: var(--gray-400); }
h1, h2, h3, h4 { line-height: 1.25; color: var(--gray-900); font-weight: 700; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
img { max-width: 100%; display: block; }

.container { max-width: 1120px; margin: 0 auto; padding: 0 24px; }

/* ═══════════════════════════════════════
   NAVBAR
   ═══════════════════════════════════════ */
.navbar {
    position: fixed; top: 0; left: 0; width: 100%; z-index: 1000;
    background: rgba(255,255,255,0.92); backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--gray-200);
    transition: var(--transition);
}
.nav-inner {
    display: flex; align-items: center; justify-content: space-between;
    height: 64px;
}
.nav-logo {
    display: flex; align-items: center; gap: 10px;
    font-size: 1.1rem; font-weight: 700; color: var(--gray-900);
}
.nav-links { display: flex; align-items: center; gap: 28px; }
.nav-links a { font-size: 0.9rem; font-weight: 500; color: var(--gray-600); transition: var(--transition); }
.nav-links a:hover { color: var(--gray-900); }
.nav-cta {
    background: var(--blue-700); color: var(--white) !important;
    padding: 8px 18px; border-radius: var(--radius-sm); font-weight: 600;
}
.nav-cta:hover { background: var(--blue-800); }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; flex-direction: column; gap: 5px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--gray-700); border-radius: 2px; }

/* ═══════════════════════════════════════
   ANNOUNCEMENT BAR
   ═══════════════════════════════════════ */
.announcement {
    margin-top: 64px;
    background: var(--amber-100); border-bottom: 1px solid #fcd34d;
    padding: 10px 0;
}
.announcement-inner { display: flex; align-items: center; gap: 12px; font-size: 0.88rem; color: var(--amber-800); flex-wrap: wrap; }
.announcement-badge {
    background: var(--amber-600); color: var(--white);
    padding: 2px 10px; border-radius: 50px; font-size: 0.75rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: 0.5px; white-space: nowrap;
}

/* ═══════════════════════════════════════
   HERO
   ═══════════════════════════════════════ */
.hero {
    padding: 80px 0 60px;
    background: linear-gradient(180deg, var(--gray-50) 0%, var(--white) 100%);
}
.hero-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.hero-eyebrow {
    font-size: 0.85rem; font-weight: 600; color: var(--blue-700);
    text-transform: uppercase; letter-spacing: 1px; margin-bottom: 16px;
}
.hero h1 { font-size: 2.8rem; margin-bottom: 20px; letter-spacing: -0.5px; }
.hero-desc { font-size: 1.05rem; color: var(--gray-600); max-width: 520px; line-height: 1.75; margin-bottom: 32px; }
.hero-buttons { display: flex; gap: 14px; flex-wrap: wrap; }

/* Buttons */
.btn {
    display: inline-flex; flex-direction: column; align-items: center; justify-content: center;
    padding: 14px 28px; border-radius: var(--radius-sm); font-weight: 600;
    font-size: 1rem; cursor: pointer; transition: var(--transition);
    border: none; text-decoration: none; gap: 2px;
}
.btn i { margin-right: 6px; }
.btn-sub { font-size: 0.72rem; font-weight: 400; opacity: 0.75; margin-top: 2px; }
.btn-primary { background: var(--blue-700); color: var(--white); }
.btn-primary:hover { background: var(--blue-800); transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn-outline { background: var(--white); color: var(--gray-700); border: 1px solid var(--gray-300); }
.btn-outline:hover { background: var(--gray-50); border-color: var(--gray-400); }
.btn-white { background: var(--white); color: var(--gray-900); }
.btn-white:hover { background: var(--gray-100); transform: translateY(-1px); }
.btn-lg { padding: 16px 32px; font-size: 1.05rem; }

/* Hero Preview */
.hero-preview { position: relative; }
.preview-window {
    background: var(--white); border: 1px solid var(--gray-200); border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl); overflow: hidden;
}
.preview-titlebar {
    height: 36px; background: var(--gray-50); border-bottom: 1px solid var(--gray-200);
    display: flex; align-items: center; padding: 0 14px; gap: 10px;
}
.preview-dots { display: flex; gap: 6px; }
.preview-dots span { width: 10px; height: 10px; border-radius: 50%; background: var(--gray-300); }
.preview-title { font-size: 0.75rem; color: var(--gray-500); font-weight: 500; }
.preview-body { display: flex; min-height: 280px; }
.preview-sidebar {
    width: 52px; background: var(--gray-50); border-right: 1px solid var(--gray-200);
    padding: 12px 0; display: flex; flex-direction: column; align-items: center; gap: 8px;
}
.preview-nav-item { width: 28px; height: 28px; border-radius: var(--radius-sm); background: var(--gray-200); }
.preview-nav-item.active { background: var(--blue-100); }
.preview-main { flex: 1; padding: 20px; display: flex; flex-direction: column; gap: 16px; }
.preview-card-row { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.preview-card {
    background: var(--gray-50); border: 1px solid var(--gray-200); border-radius: var(--radius-sm);
    padding: 14px; display: flex; gap: 10px; align-items: flex-start;
}
.preview-card-icon { font-size: 1.2rem; }
.preview-card-lines { flex: 1; display: flex; flex-direction: column; gap: 6px; padding-top: 4px; }
.preview-text-block { display: flex; flex-direction: column; gap: 8px; }
.skel { height: 8px; background: var(--gray-200); border-radius: 4px; }
.skel-w100 { width: 100%; } .skel-w90 { width: 90%; } .skel-w80 { width: 80%; }
.skel-w70 { width: 70%; } .skel-w60 { width: 60%; } .skel-w50 { width: 50%; } .skel-w40 { width: 40%; }

/* ═══════════════════════════════════════
   STATS BAR
   ═══════════════════════════════════════ */
.stats { padding: 48px 0; border-top: 1px solid var(--gray-200); border-bottom: 1px solid var(--gray-200); background: var(--gray-50); }
.stats-inner { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; text-align: center; }
.stat-item { display: flex; flex-direction: column; gap: 4px; }
.stat-number { font-size: 2rem; font-weight: 800; color: var(--blue-700); }
.stat-label { font-size: 0.85rem; font-weight: 500; color: var(--gray-500); text-transform: uppercase; letter-spacing: 0.5px; }

/* ═══════════════════════════════════════
   SECTION HEADERS
   ═══════════════════════════════════════ */
.section-head { text-align: center; max-width: 680px; margin: 0 auto 56px; }
.section-label {
    font-size: 0.82rem; font-weight: 700; color: var(--blue-700);
    text-transform: uppercase; letter-spacing: 1.5px; margin-bottom: 12px;
}
.section-head h2 { font-size: 2.2rem; margin-bottom: 16px; }
.section-desc { color: var(--gray-600); font-size: 1.05rem; }

/* ═══════════════════════════════════════
   FEATURES
   ═══════════════════════════════════════ */
.features { padding: 100px 0; }
.feature-row {
    display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center;
    margin-bottom: 80px;
}
.feature-row:last-child { margin-bottom: 0; }
.feature-row.reverse { direction: rtl; }
.feature-row.reverse > * { direction: ltr; }

.feature-badge {
    display: inline-flex; align-items: center; gap: 8px;
    font-size: 0.82rem; font-weight: 700; color: var(--blue-700);
    text-transform: uppercase; letter-spacing: 0.5px; margin-bottom: 12px;
}
.feature-text h3 { font-size: 1.7rem; margin-bottom: 14px; }
.feature-text > p { color: var(--gray-600); margin-bottom: 20px; font-size: 0.98rem; }
.feature-list { display: flex; flex-direction: column; gap: 10px; }
.feature-list li {
    display: flex; align-items: flex-start; gap: 10px;
    font-size: 0.92rem; color: var(--gray-700); line-height: 1.5;
}
.feature-list li i { color: var(--green-500); margin-top: 3px; font-size: 0.8rem; flex-shrink: 0; }

/* Feature Visuals */
.fv-box {
    background: var(--gray-50); border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg); padding: 28px; min-height: 260px;
    display: flex; align-items: center; justify-content: center;
}

/* Reader Mock */
.fv-reader-mock {
    font-size: 1rem; color: var(--gray-700); line-height: 2; padding: 0 8px;
}
.fv-highlight {
    display: inline; padding: 2px 6px; border-radius: 3px; font-weight: 600;
}
.fv-highlight.red { background: #fee2e2; color: #991b1b; }
.fv-highlight.blue { background: #dbeafe; color: #1e40af; }
.fv-highlight.green { background: #dcfce7; color: #166534; }
.fv-toolbar {
    display: flex; align-items: center; gap: 14px; margin-top: 20px;
    padding: 10px 14px; background: var(--white); border: 1px solid var(--gray-200);
    border-radius: var(--radius-sm); font-size: 0.82rem; color: var(--gray-500);
}
.fv-dot { width: 14px; height: 14px; border-radius: 50%; }
.fv-dot.red { background: #fca5a5; }
.fv-dot.blue { background: #93c5fd; }
.fv-dot.green { background: #86efac; }
.fv-tool { padding: 4px 10px; background: var(--gray-100); border-radius: 4px; cursor: default; }

/* Dictionary Mock */
.fv-dict-card { width: 100%; }
.fv-dict-letter {
    font-size: 1.4rem; font-weight: 800; color: var(--blue-700);
    border-bottom: 2px solid var(--blue-100); padding-bottom: 6px; margin-bottom: 16px;
}
.fv-dict-item {
    display: flex; flex-direction: column; gap: 4px; padding: 12px 0;
    border-bottom: 1px solid var(--gray-200);
}
.fv-dict-item:last-child { border-bottom: none; }
.fv-dict-item strong { font-size: 1rem; color: var(--gray-900); }
.fv-dict-def { font-size: 0.88rem; color: var(--gray-600); }
.fv-dict-example { font-size: 0.82rem; color: var(--gray-400); font-style: italic; }

/* Practice Mock */
.fv-practice-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; width: 100%; }
.fv-practice-card {
    background: var(--white); border: 1px solid var(--gray-200);
    border-radius: var(--radius-md); padding: 20px;
    display: flex; flex-direction: column; align-items: center; gap: 8px; text-align: center;
    font-size: 0.88rem; font-weight: 600; color: var(--gray-700);
    transition: var(--transition);
}
.fv-practice-card:hover { border-color: var(--blue-600); box-shadow: var(--shadow-sm); }
.fv-practice-icon { font-size: 1.6rem; }

/* Shadowing Mock */
.fv-shadowing { text-align: center; width: 100%; }
.fv-wave { display: flex; align-items: center; justify-content: center; gap: 3px; margin-bottom: 20px; height: 40px; }
.fv-wave span {
    width: 3px; border-radius: 3px; background: var(--blue-600);
    animation: wave 1.2s ease-in-out infinite;
}
.fv-wave span:nth-child(1)  { height: 12px; animation-delay: 0s; }
.fv-wave span:nth-child(2)  { height: 20px; animation-delay: 0.1s; }
.fv-wave span:nth-child(3)  { height: 30px; animation-delay: 0.2s; }
.fv-wave span:nth-child(4)  { height: 24px; animation-delay: 0.3s; }
.fv-wave span:nth-child(5)  { height: 36px; animation-delay: 0.4s; }
.fv-wave span:nth-child(6)  { height: 28px; animation-delay: 0.5s; }
.fv-wave span:nth-child(7)  { height: 18px; animation-delay: 0.6s; }
.fv-wave span:nth-child(8)  { height: 32px; animation-delay: 0.7s; }
.fv-wave span:nth-child(9)  { height: 22px; animation-delay: 0.8s; }
.fv-wave span:nth-child(10) { height: 14px; animation-delay: 0.9s; }
.fv-wave span:nth-child(11) { height: 26px; animation-delay: 1s; }
.fv-wave span:nth-child(12) { height: 34px; animation-delay: 0.15s; }
.fv-wave span:nth-child(13) { height: 20px; animation-delay: 0.35s; }
.fv-wave span:nth-child(14) { height: 28px; animation-delay: 0.55s; }
.fv-wave span:nth-child(15) { height: 16px; animation-delay: 0.75s; }

@keyframes wave {
    0%, 100% { transform: scaleY(0.5); opacity: 0.5; }
    50% { transform: scaleY(1); opacity: 1; }
}
.fv-shad-text { font-size: 1rem; color: var(--gray-700); font-style: italic; margin-bottom: 16px; }
.fv-shad-controls { display: flex; justify-content: center; gap: 20px; font-size: 1.2rem; color: var(--gray-400); }
.fv-play-btn { color: var(--blue-600); font-size: 1.5rem; }

/* Notes Mock */
.fv-notes { width: 100%; }
.fv-note-group { background: var(--white); border: 1px solid var(--gray-200); border-radius: var(--radius-md); overflow: hidden; }
.fv-note-header {
    padding: 14px 18px; font-weight: 700; font-size: 0.92rem; color: var(--gray-800);
    background: var(--gray-50); border-bottom: 1px solid var(--gray-200);
}
.fv-note-entry {
    padding: 12px 18px; font-size: 0.88rem; color: var(--gray-600);
    border-bottom: 1px solid var(--gray-100); font-style: italic;
}
.fv-note-entry:last-child { border-bottom: none; }

/* Jungle Mock */
.fv-jungle { text-align: center; width: 100%; }
.fv-jungle-svg { width: 220px; height: auto; }

/* ═══════════════════════════════════════
   HOW IT WORKS
   ═══════════════════════════════════════ */
.how-it-works { padding: 100px 0; background: var(--gray-50); border-top: 1px solid var(--gray-200); }
.steps-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.step-card {
    background: var(--white); border: 1px solid var(--gray-200); border-radius: var(--radius-lg);
    padding: 32px 24px; transition: var(--transition);
}
.step-card:hover { border-color: var(--blue-100); box-shadow: var(--shadow-md); }
.step-num { font-size: 2rem; font-weight: 800; color: var(--blue-100); margin-bottom: 16px; }
.step-card h4 { font-size: 1.1rem; margin-bottom: 10px; }
.step-card p { font-size: 0.9rem; color: var(--gray-600); }

/* ═══════════════════════════════════════
   TECH STACK
   ═══════════════════════════════════════ */
.tech { padding: 100px 0; }
.tech-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 16px; }
.tech-card {
    background: var(--gray-50); border: 1px solid var(--gray-200); border-radius: var(--radius-md);
    padding: 24px 16px; text-align: center;
    display: flex; flex-direction: column; align-items: center; gap: 10px;
    transition: var(--transition);
}
.tech-card:hover { border-color: var(--blue-100); box-shadow: var(--shadow-sm); }
.tech-card i { font-size: 1.8rem; color: var(--blue-700); }
.tech-card span { font-size: 0.85rem; font-weight: 600; color: var(--gray-700); }

/* ═══════════════════════════════════════
   CTA
   ═══════════════════════════════════════ */
.cta { padding: 80px 0; }
.cta-box {
    background: var(--blue-700); color: var(--white); text-align: center;
    padding: 64px 40px; border-radius: var(--radius-xl);
}
.cta-box h2 { font-size: 2.2rem; color: var(--white); margin-bottom: 14px; }
.cta-box > p { color: #bfdbfe; font-size: 1.05rem; margin-bottom: 28px; max-width: 560px; margin-left: auto; margin-right: auto; }
.cta-buttons { margin-bottom: 20px; }
.cta-note { font-size: 0.78rem; color: #93c5fd; max-width: 480px; margin: 0 auto; }

/* ═══════════════════════════════════════
   FOOTER
   ═══════════════════════════════════════ */
footer { background: var(--gray-950); color: var(--gray-400); padding: 60px 0 0; }
.footer-inner { display: flex; justify-content: space-between; gap: 40px; flex-wrap: wrap; padding-bottom: 40px; }
.footer-brand { max-width: 360px; }
.footer-brand .nav-logo { margin-bottom: 16px; }
.footer-brand .nav-logo span { color: var(--white); }
.footer-brand p { font-size: 0.9rem; line-height: 1.7; }
.footer-links-group { display: flex; flex-direction: column; gap: 10px; }
.footer-links-group h4 { color: var(--white); font-size: 0.9rem; margin-bottom: 4px; }
.footer-links-group a { color: var(--gray-400); font-size: 0.88rem; display: flex; align-items: center; gap: 8px; transition: var(--transition); }
.footer-links-group a:hover { color: var(--white); }
.footer-bottom { border-top: 1px solid #1f2937; padding: 20px 0; }
.footer-bottom p { font-size: 0.8rem; color: var(--gray-500); }

/* ═══════════════════════════════════════
   ANIMATIONS
   ═══════════════════════════════════════ */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.active { opacity: 1; transform: translateY(0); }
.delay-1 { transition-delay: 0.1s; }
.delay-2 { transition-delay: 0.2s; }
.delay-3 { transition-delay: 0.3s; }

/* ═══════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════ */
@media (max-width: 1024px) {
    .hero-inner { grid-template-columns: 1fr; gap: 40px; }
    .feature-row, .feature-row.reverse { grid-template-columns: 1fr; direction: ltr; gap: 32px; }
    .steps-grid { grid-template-columns: repeat(2, 1fr); }
    .tech-grid { grid-template-columns: repeat(3, 1fr); }
    .stats-inner { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
    .nav-links { display: none; position: absolute; top: 64px; left: 0; width: 100%; background: var(--white); flex-direction: column; padding: 20px 24px; gap: 16px; border-bottom: 1px solid var(--gray-200); box-shadow: var(--shadow-lg); }
    .nav-links.active { display: flex; }
    .nav-toggle { display: flex; }
    .hero h1 { font-size: 2rem; }
    .hero-buttons { flex-direction: column; }
    .btn-lg { width: 100%; }
    .section-head h2 { font-size: 1.6rem; }
    .feature-text h3 { font-size: 1.3rem; }
    .steps-grid { grid-template-columns: 1fr; }
    .tech-grid { grid-template-columns: repeat(2, 1fr); }
    .stats-inner { grid-template-columns: repeat(2, 1fr); gap: 24px; }
    .cta-box { padding: 40px 24px; }
    .cta-box h2 { font-size: 1.6rem; }
}