/* Let's Do Our Best — Online English Lessons */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; border: none; background: none; }
input, textarea, select { font: inherit; }

:root {
  --primary: #1E40AF;
  --primary-dark: #1E3A8A;
  --primary-light: #DBEAFE;
  --accent: #F97316;
  --accent-light: #FED7AA;
  --warm: #FBBF24;
  --text: #1E293B;
  --text-light: #64748B;
  --text-muted: #94A3B8;
  --surface: #F8FAFC;
  --surface-2: #F1F5F9;
  --border: #E2E8F0;
  --white: #FFFFFF;
  --success: #10B981;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-display: "Segoe UI", -apple-system, BlinkMacSystemFont, sans-serif;

  --space-1: 0.25rem; --space-2: 0.5rem; --space-3: 0.75rem; --space-4: 1rem;
  --space-5: 1.25rem; --space-6: 1.5rem; --space-8: 2rem; --space-10: 2.5rem;
  --space-12: 3rem; --space-16: 4rem; --space-20: 5rem; --space-24: 6rem;

  --radius-sm: 6px; --radius: 10px; --radius-lg: 18px; --radius-xl: 24px; --radius-full: 999px;

  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.05);
  --shadow: 0 4px 12px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 16px 40px rgba(15, 23, 42, 0.12);
}

body {
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--white);
  line-height: 1.6;
  font-size: 17px;
}

.container { max-width: 1180px; margin: 0 auto; padding: 0 var(--space-6); }

h1, h2, h3, h4 { font-family: var(--font-display); font-weight: 700; line-height: 1.15; color: var(--text); letter-spacing: -0.02em; }
h1 { font-size: clamp(2.25rem, 5vw, 3.75rem); }
h2 { font-size: clamp(1.75rem, 3.5vw, 2.5rem); }
h3 { font-size: 1.35rem; }
h4 { font-size: 1.1rem; }
p { color: var(--text-light); }
.eyebrow { font-size: 0.85rem; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: var(--accent); display: inline-block; margin-bottom: var(--space-3); }
.lead { font-size: 1.2rem; color: var(--text-light); }

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2);
  padding: var(--space-3) var(--space-6); border-radius: var(--radius-full);
  font-weight: 600; font-size: 1rem; transition: all 0.2s ease;
  border: 2px solid transparent;
}
.btn-primary { background: var(--primary); color: var(--white); }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-1px); box-shadow: var(--shadow); }
.btn-secondary { background: var(--white); color: var(--primary); border-color: var(--primary); }
.btn-secondary:hover { background: var(--primary-light); }
.btn-accent { background: var(--accent); color: var(--white); }
.btn-accent:hover { background: #EA580C; transform: translateY(-1px); box-shadow: var(--shadow); }
.btn-lg { padding: var(--space-4) var(--space-8); font-size: 1.05rem; }

/* ===== NAV ===== */
.site-nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  padding: var(--space-4) 0;
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; gap: var(--space-6); }
.brand { display: flex; align-items: center; gap: var(--space-3); font-weight: 800; font-size: 1.1rem; color: var(--text); }
.brand-mark {
  width: 40px; height: 40px; border-radius: var(--radius);
  background: linear-gradient(135deg, var(--primary), var(--accent));
  display: flex; align-items: center; justify-content: center;
  color: var(--white); font-weight: 800; font-size: 1.05rem;
}
.nav-links { display: flex; align-items: center; gap: var(--space-8); list-style: none; }
.nav-links a { color: var(--text-light); font-weight: 500; transition: color 0.2s; }
.nav-links a:hover, .nav-links a.active { color: var(--primary); }
.nav-cta { display: flex; align-items: center; gap: var(--space-3); }
.nav-toggle { display: none; padding: var(--space-2); }
.nav-toggle svg { width: 26px; height: 26px; stroke: var(--text); }

@media (max-width: 880px) {
  .nav-toggle { display: block; }
  .nav-links, .nav-cta { display: none; }
  .nav-links.open {
    display: flex; flex-direction: column; gap: var(--space-4);
    position: absolute; top: 100%; left: 0; right: 0;
    background: var(--white); padding: var(--space-6);
    border-bottom: 1px solid var(--border); box-shadow: var(--shadow);
  }
}

/* ===== HERO ===== */
.hero { padding: var(--space-16) 0 var(--space-20); background: linear-gradient(180deg, var(--surface) 0%, var(--white) 100%); }
.hero-grid { display: grid; grid-template-columns: 1.05fr 1fr; gap: var(--space-12); align-items: center; }
.hero h1 { margin-bottom: var(--space-5); }
.hero h1 .accent {
  display: inline-block; position: relative;
  background: linear-gradient(120deg, transparent 0%, transparent 50%, var(--warm) 50%, var(--warm) 95%, transparent 95%);
  background-size: 200% 0.4em; background-repeat: no-repeat; background-position: 100% 88%;
  padding: 0 0.1em;
}
.hero p.lead { margin-bottom: var(--space-8); max-width: 540px; }
.hero-actions { display: flex; gap: var(--space-4); flex-wrap: wrap; }
.hero-photo {
  position: relative; aspect-ratio: 4 / 5;
  border-radius: var(--radius-lg);
  overflow: hidden; box-shadow: var(--shadow-lg);
  background: var(--surface);
}
.hero-photo img { width: 100%; height: 100%; object-fit: cover; }
.hero-photo::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(30, 64, 175, 0.12) 0%, transparent 40%, transparent 60%, rgba(249, 115, 22, 0.12) 100%);
  pointer-events: none;
}

@media (max-width: 880px) {
  .hero { padding: var(--space-10) 0 var(--space-12); }
  .hero-grid { grid-template-columns: 1fr; gap: var(--space-8); }
  .hero-photo { aspect-ratio: 3 / 2; max-width: 600px; margin: 0 auto; }
}

/* ===== TRUST / STATS BAR ===== */
.stats-bar {
  background: var(--white); padding: var(--space-8) 0;
  border-top: 1px solid var(--border); border-bottom: 1px solid var(--border);
}
.stats-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-6); text-align: center;
}
.stat-num { font-size: 2rem; font-weight: 800; color: var(--primary); display: block; line-height: 1; }
.stat-label { font-size: 0.9rem; color: var(--text-light); margin-top: var(--space-2); }
@media (max-width: 720px) {
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: var(--space-8); }
}

/* ===== SECTIONS ===== */
.section { padding: var(--space-20) 0; }
.section-tight { padding: var(--space-16) 0; }
.section-light { background: var(--surface); }
.section-primary { background: var(--primary); color: var(--white); }
.section-primary h1, .section-primary h2, .section-primary h3 { color: var(--white); }
.section-primary p { color: rgba(255, 255, 255, 0.85); }
.section-header { text-align: center; max-width: 720px; margin: 0 auto var(--space-12); }

/* ===== STEPS (How it works) ===== */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-8); }
.step {
  background: var(--white); padding: var(--space-8);
  border-radius: var(--radius-lg); border: 1px solid var(--border);
  position: relative; transition: all 0.3s ease;
}
.step:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: var(--primary-light); }
.step-num {
  width: 48px; height: 48px; border-radius: var(--radius-full);
  background: var(--primary-light); color: var(--primary);
  display: flex; align-items: center; justify-content: center;
  font-weight: 800; font-size: 1.2rem; margin-bottom: var(--space-5);
}
.step h3 { margin-bottom: var(--space-3); }
@media (max-width: 880px) { .steps { grid-template-columns: 1fr; } }

/* ===== SERVICE CARDS ===== */
.services-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-6); }
.service-card {
  background: var(--white); padding: var(--space-8);
  border-radius: var(--radius-lg); border: 1px solid var(--border);
  display: flex; flex-direction: column; gap: var(--space-3);
  transition: all 0.3s ease; position: relative; overflow: hidden;
}
.service-card::before {
  content: ""; position: absolute; top: 0; left: 0; right: 0; height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transform: scaleX(0); transform-origin: left; transition: transform 0.3s ease;
}
.service-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.service-card:hover::before { transform: scaleX(1); }
.service-icon {
  width: 56px; height: 56px; border-radius: var(--radius);
  background: var(--primary-light); color: var(--primary);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.5rem; margin-bottom: var(--space-2);
}
.service-card.kids .service-icon { background: var(--accent-light); color: var(--accent); }
.service-meta { display: flex; gap: var(--space-3); flex-wrap: wrap; margin-top: var(--space-3); }
.tag {
  display: inline-block; padding: var(--space-1) var(--space-3);
  background: var(--surface); color: var(--text-light);
  border-radius: var(--radius-full); font-size: 0.85rem; font-weight: 500;
}
.tag-price { background: var(--primary-light); color: var(--primary); font-weight: 600; }
@media (max-width: 720px) { .services-grid { grid-template-columns: 1fr; } }

/* ===== PRICING ===== */
.pricing-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-6); align-items: stretch; }
.plan {
  background: var(--white); padding: var(--space-8);
  border-radius: var(--radius-lg); border: 2px solid var(--border);
  display: flex; flex-direction: column; transition: all 0.3s ease;
  position: relative;
}
.plan:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.plan.featured { border-color: var(--primary); transform: scale(1.04); box-shadow: var(--shadow-lg); }
.plan.featured::before {
  content: "Most Popular"; position: absolute; top: -14px; left: 50%; transform: translateX(-50%);
  background: var(--accent); color: var(--white); padding: var(--space-1) var(--space-4);
  border-radius: var(--radius-full); font-size: 0.8rem; font-weight: 700; letter-spacing: 0.05em;
}
.plan-name { font-size: 1.3rem; font-weight: 700; color: var(--text); }
.plan-tier { color: var(--text-muted); font-size: 0.9rem; margin-bottom: var(--space-4); }
.plan-price { font-size: 2.5rem; font-weight: 800; color: var(--primary); line-height: 1; }
.plan-period { color: var(--text-light); font-size: 0.95rem; margin-bottom: var(--space-6); }
.plan-features { list-style: none; margin-bottom: var(--space-8); flex-grow: 1; }
.plan-features li {
  padding: var(--space-3) 0; border-bottom: 1px solid var(--border);
  display: flex; align-items: flex-start; gap: var(--space-3); color: var(--text-light);
}
.plan-features li::before {
  content: "✓"; color: var(--success); font-weight: 700; flex-shrink: 0;
}
.plan-features li:last-child { border-bottom: none; }
.plan-savings { display: inline-block; background: var(--accent-light); color: #C2410C; padding: var(--space-1) var(--space-3); border-radius: var(--radius-full); font-size: 0.85rem; font-weight: 600; margin-bottom: var(--space-4); }
@media (max-width: 880px) {
  .pricing-grid { grid-template-columns: 1fr; gap: var(--space-8); }
  .plan.featured { transform: none; }
}

/* ===== INSTRUCTORS ===== */
.instructors-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-6); }
.instructor-card {
  background: var(--white); padding: var(--space-6); text-align: center;
  border-radius: var(--radius-lg); border: 1px solid var(--border);
  transition: all 0.3s ease;
}
.instructor-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.instructor-avatar {
  width: 96px; height: 96px; margin: 0 auto var(--space-4);
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, var(--primary), var(--accent));
  display: flex; align-items: center; justify-content: center;
  color: var(--white); font-weight: 700; font-size: 2rem;
}
.instructor-name { font-weight: 700; font-size: 1.1rem; margin-bottom: var(--space-1); color: var(--text); }
.instructor-country { color: var(--text-light); font-size: 0.9rem; display: flex; align-items: center; justify-content: center; gap: var(--space-2); }
.instructor-flag { font-size: 1.1rem; }
@media (max-width: 880px) { .instructors-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 480px) { .instructors-grid { grid-template-columns: 1fr; } }

/* ===== TWO COL ===== */
.two-col { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-12); align-items: center; }
.two-col-image {
  aspect-ratio: 4 / 3; border-radius: var(--radius-lg);
  overflow: hidden; box-shadow: var(--shadow-lg); position: relative; background: var(--surface);
}
.two-col-image img { width: 100%; height: 100%; object-fit: cover; }
.two-col blockquote {
  border-left: 3px solid var(--accent); padding-left: var(--space-5);
  margin: var(--space-6) 0; color: var(--text); font-style: italic; font-size: 1.1rem;
}
@media (max-width: 880px) { .two-col { grid-template-columns: 1fr; gap: var(--space-8); } }

/* ===== CTA BLOCK ===== */
.cta-block {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: var(--white); padding: var(--space-16) var(--space-12);
  border-radius: var(--radius-xl); text-align: center; margin: var(--space-12) 0;
  position: relative; overflow: hidden;
}
.cta-block::before {
  content: ""; position: absolute; top: -50%; right: -10%; width: 50%; height: 200%;
  background: radial-gradient(circle, rgba(249, 115, 22, 0.2) 0%, transparent 60%);
  pointer-events: none;
}
.cta-block h2 { color: var(--white); margin-bottom: var(--space-4); position: relative; }
.cta-block p { color: rgba(255, 255, 255, 0.9); margin-bottom: var(--space-8); max-width: 580px; margin-left: auto; margin-right: auto; position: relative; }
.cta-block .btn-accent { position: relative; }

/* ===== FORM ===== */
.contact-form {
  background: var(--white); padding: var(--space-8);
  border-radius: var(--radius-lg); border: 1px solid var(--border); box-shadow: var(--shadow);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); margin-bottom: var(--space-4); }
.form-group { display: flex; flex-direction: column; gap: var(--space-2); margin-bottom: var(--space-4); }
.form-group label { font-weight: 600; font-size: 0.9rem; color: var(--text); }
.form-group input, .form-group textarea, .form-group select {
  padding: var(--space-3) var(--space-4); border: 1px solid var(--border);
  border-radius: var(--radius); background: var(--white); font-size: 1rem; transition: border-color 0.2s;
}
.form-group input:focus, .form-group textarea:focus, .form-group select:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-light); }
.form-group textarea { resize: vertical; min-height: 120px; }
@media (max-width: 720px) { .form-row { grid-template-columns: 1fr; } }

/* ===== FOOTER ===== */
.site-footer { background: var(--text); color: rgba(255, 255, 255, 0.85); padding: var(--space-16) 0 var(--space-8); }
.site-footer h4 { color: var(--white); margin-bottom: var(--space-4); font-size: 1rem; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: var(--space-8); margin-bottom: var(--space-12); }
.footer-grid a { color: rgba(255, 255, 255, 0.7); transition: color 0.2s; display: block; padding: var(--space-1) 0; }
.footer-grid a:hover { color: var(--white); }
.footer-brand p { color: rgba(255, 255, 255, 0.7); margin-top: var(--space-3); }
.footer-bottom { border-top: 1px solid rgba(255, 255, 255, 0.15); padding-top: var(--space-6); display: flex; justify-content: space-between; flex-wrap: wrap; gap: var(--space-4); color: rgba(255, 255, 255, 0.6); font-size: 0.9rem; }
@media (max-width: 880px) { .footer-grid { grid-template-columns: 1fr 1fr; gap: var(--space-6); } }
@media (max-width: 480px) { .footer-grid { grid-template-columns: 1fr; } }

/* ===== PAGE HEADER ===== */
.page-header {
  background: linear-gradient(180deg, var(--surface) 0%, var(--white) 100%);
  padding: var(--space-16) 0 var(--space-12); text-align: center;
  border-bottom: 1px solid var(--border);
}
.page-header h1 { margin-bottom: var(--space-4); }
.page-header p { font-size: 1.15rem; max-width: 640px; margin: 0 auto; }

/* ===== UTILITY ===== */
.text-center { text-align: center; }
.mt-4 { margin-top: var(--space-4); }
.mt-8 { margin-top: var(--space-8); }
.mb-8 { margin-bottom: var(--space-8); }