/* --- Новая цветовая палитра: Чёрно-белый стиль --- */
:root {
  --bg-color: #ffffff;
  --primary-color: #000000;
  --secondary-color: #333333;
  --text-color: #000000;
  --heading-color: #000000;
  --border-color: #0000001a;
  --font-main: 'Plus Jakarta Sans', sans-serif;
  --shadow-color: rgba(0, 0, 0, 0.1);
  --accent-text-gradient: linear-gradient(45deg, #000000, #333333);
  --transition-ease: all 0.4s ease;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-main);
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.7;
  overflow-x: hidden;
}

/* --- Aurora Background (перекрашены в чёрный/серый) --- */
.aurora-background { position: fixed; top: 0; left: 0; width: 100%; height: 100%; z-index: -1; overflow: hidden; }
.aurora-shape { position: absolute; border-radius: 50%; filter: blur(180px); opacity: 0.15; }
.shape1 { width: 700px; height: 700px; background: var(--primary-color); top: -250px; left: -250px; animation: move1 25s infinite alternate; }
.shape2 { width: 600px; height: 600px; background: var(--secondary-color); bottom: -200px; right: -200px; animation: move2 30s infinite alternate; }
.shape3 { width: 500px; height: 500px; background: #000000; bottom: 50px; left: 150px; animation: move3 22s infinite alternate; }

@keyframes move1 { from { transform: translate(0, 0) rotate(0deg); } to { transform: translate(250px, 350px) rotate(120deg); } }
@keyframes move2 { from { transform: translate(0, 0) rotate(0deg); } to { transform: translate(-350px, -250px) rotate(200deg); } }
@keyframes move3 { from { transform: translate(0, 0) rotate(0deg); } to { transform: translate(150px, -250px) rotate(60deg); } }

/* --- General --- */
.container { max-width: 1100px; margin: 0 auto; padding: 0 20px; }
h1, h2, h3 { color: var(--heading-color); font-weight: 800; }
h2 { font-size: 2.8rem; text-align: center; margin-bottom: 60px; line-height: 1.3; }
.accent-text { background: var(--accent-text-gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
section { padding: 120px 0; }
.section-description { text-align: center; max-width: 700px; margin: 0 auto 40px; font-size: 1.1rem; opacity: 0.9; }

/* --- Navigation --- */
.navbar {
  padding: 20px 0;
  position: fixed;
  width: 100%;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  transition: var(--transition-ease);
}
.navbar.scrolled { background: rgba(255, 255, 255, 0.95); padding: 15px 0; }
.navbar .container { display: flex; justify-content: space-between; align-items: center; }
.logo { font-size: 1.8rem; font-weight: 800; text-decoration: none; color: var(--heading-color); }
.logo span { color: var(--primary-color); }
.nav-links { display: flex; list-style: none; align-items: center; }
.nav-links li a { color: var(--heading-color); text-decoration: none; margin-left: 35px; font-weight: 500; transition: var(--transition-ease); }
.nav-links li a:hover { color: var(--primary-color); }
/* --- ОБНОВЛЁННАЯ КНОПКА --- */
.btn-nav {
  background: white;
  color: var(--bg-color); /* Чёрный текст */
  padding: 10px 25px;
  border-radius: 50px;
  font-weight: 700;
  transition: var(--transition-ease);
  border: 2px solid white; /* Белый бордер */
  text-decoration: none;
}
.btn-nav:hover {
  background: var(--accent-color); /* При наведении становится акцентной */
  color: white;
  border-color: var(--accent-color);
  transform: translateY(-2px);
  box-shadow: 0 5px 15px var(--shadow-color);
}

/* --- Hero Section --- */
.hero { min-height: 100vh; display: flex; align-items: center; text-align: center; }
.hero-content h1 { font-size: 3.8rem; line-height: 1.2; margin-bottom: 25px; }
.hero-content .subtitle { font-size: 1.25rem; margin-bottom: 40px; max-width: 700px; margin-left: auto; margin-right: auto; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--primary-color);
  color: white;
  padding: 18px 40px;
  border-radius: 50px;
  text-decoration: none;
  font-weight: 700;
  font-size: 1.1rem;
  transition: var(--transition-ease);
  border: 2px solid var(--primary-color);
  box-shadow: 0 5px 20px var(--shadow-color);
  cursor: pointer;
}
.btn i { margin-right: 12px; font-size: 1.2rem; }
.btn:hover { transform: translateY(-5px) scale(1.05); box-shadow: 0 10px 30px var(--shadow-color); background: var(--secondary-color); }

/* --- Stats Section (#our-weapon) --- */
#our-weapon { padding-top: 0; }
.stats-grid { display: flex; justify-content: center; gap: 60px; flex-wrap: wrap; }
.stat-item { text-align: center; }
.stat-number {
  font-size: 5rem;
  font-weight: 800;
  color: var(--heading-color);
  line-height: 1;
  background: var(--accent-text-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  transition: transform 0.3s;
}
.stat-number:hover { transform: scale(1.05); }
.stat-label { font-size: 1rem; color: var(--text-color); margin-top: 10px; }
.stat-label strong { color: var(--heading-color); font-weight: 700; }

/* --- Why Us & Cards --- */
#why-us { background: #fafafa; }
.why-us-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 30px; }
.card {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: 15px;
  padding: 40px 30px;
  text-align: center;
  transition: var(--transition-ease);
  box-shadow: 0 5px 15px var(--shadow-color);
}
.card:hover { transform: translateY(-10px); border-color: var(--primary-color); box-shadow: 0 15px 30px var(--shadow-color); }
.card-icon {
  width: 70px;
  height: 70px;
  margin: 0 auto 30px;
  background: var(--primary-color);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  box-shadow: 0 5px 20px var(--shadow-color);
  transition: var(--transition-ease);
}
.card:hover .card-icon { transform: scale(1.1); }
.card h3 { font-size: 1.5rem; margin-bottom: 15px; }

/* --- NEW: How It Works Section --- */
#how-it-works { background: #ffffff; }
.how-it-works-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 30px; }
.how-it-works-step {
  background: #f9f9f9;
  border: 1px solid var(--border-color);
  border-radius: 15px;
  padding: 30px;
  text-align: center;
  transition: var(--transition-ease);
  box-shadow: 0 5px 15px var(--shadow-color);
}
.how-it-works-step:hover { transform: translateY(-5px); box-shadow: 0 10px 25px var(--shadow-color); }
.step-number {
  width: 50px;
  height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--primary-color);
  color: white;
  border-radius: 50%;
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 auto 20px;
}
.how-it-works-step h3 { font-size: 1.4rem; margin-bottom: 15px; }
.how-it-works-step p { font-size: 1rem; }

/* --- Proof Section --- */
#proof { background: #ffffff; }
.proof-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 30px; }
.proof-card {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: 15px;
  overflow: hidden;
  transition: var(--transition-ease);
  display: flex;
  flex-direction: column;
  box-shadow: 0 5px 15px var(--shadow-color);
}
.proof-card:hover { transform: translateY(-10px); box-shadow: 0 15px 30px var(--shadow-color); }
.proof-image { display: block; width: 100%; height: 300px; object-fit: cover; cursor: pointer; transition: transform 0.3s; }
.proof-card:hover .proof-image { transform: scale(1.05); }
.proof-caption { padding: 25px; text-align: center; background: #f5f5f5; flex-grow: 1; }
.proof-caption h3 { font-size: 1.3rem; margin-bottom: 5px; color: var(--primary-color); }
.proof-caption p { font-size: 0.95rem; opacity: 0.8; }

/* --- About Us Section --- */
.about-content { display: flex; justify-content: center; }
.tutor-card {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: 15px;
  backdrop-filter: blur(10px);
  padding: 40px 30px;
  text-align: center;
  max-width: 600px;
  display: flex;
  flex-direction: column;
  align-items: center;
  box-shadow: 0 5px 15px var(--shadow-color);
  transition: var(--transition-ease);
}
.tutor-card:hover { transform: translateY(-5px); }
.tutor-photo-wrapper { margin: 0 auto 25px; }
.tutor-photo { width: 180px; height: 180px; object-fit: cover; border-radius: 50%; box-shadow: 0 0 20px var(--shadow-color); border: 3px solid var(--primary-color); transition: var(--transition-ease); }
.tutor-card:hover .tutor-photo { transform: scale(1.08) rotate(3deg); }
.tutor-text h3 { font-size: 1.8rem; margin-bottom: 10px; }
.tutor-subjects { font-size: 1rem; font-weight: 500; color: var(--primary-color); margin-bottom: 15px; }
.tutor-subjects i { margin: 0 5px 0 15px; }
.tutor-subjects i:first-child { margin-left: 0; }
.tutor-text p { text-align: center; }

/* --- FAQ Section --- */
#faq { background: #fafafa; }
.faq-container { max-width: 800px; margin: 0 auto; }
.faq-item { background: #ffffff; border: 1px solid var(--border-color); border-radius: 10px; margin-bottom: 15px; overflow: hidden; transition: var(--transition-ease); }
.faq-item:hover { box-shadow: 0 5px 15px var(--shadow-color); }
.faq-question { background: none; border: none; width: 100%; padding: 20px 25px; text-align: left; font-size: 1.2rem; font-weight: 700; color: var(--heading-color); display: flex; justify-content: space-between; align-items: center; cursor: pointer; }
.faq-question i { transition: transform 0.3s ease; }
.faq-answer { max-height: 0; overflow: hidden; transition: max-height 0.4s ease, padding 0.4s ease; }
.faq-answer p { padding: 0 25px 20px; line-height: 1.8; }
.faq-item.active .faq-question i { transform: rotate(180deg); }
.faq-item.active .faq-answer { max-height: 200px; }

/* --- Contact Section --- */
#contact { background: linear-gradient(rgba(255, 255, 255, 0.95), rgba(255, 255, 255, 1)); }
.contact-button-wrapper { text-align: center; }

/* --- Footer --- */
footer { text-align: center; padding: 30px 0; background: #f0f0f0; color: #666; font-size: 0.9rem; }

/* --- Lightbox --- */
.lightbox { display: none; position: fixed; z-index: 2000; padding: 50px 20px; left: 0; top: 0; width: 100%; height: 100%; overflow: auto; background-color: rgba(0, 0, 0, 0.9); backdrop-filter: blur(8px); }
.lightbox-content { margin: auto; display: block; max-width: 90%; max-height: 90vh; animation: zoomIn 0.5s; }
.lightbox-close { position: absolute; top: 15px; right: 35px; color: #f1f1f1; font-size: 40px; font-weight: bold; transition: 0.3s; }
.lightbox-close:hover, .lightbox-close:focus { color: #bbb; text-decoration: none; cursor: pointer; }
@keyframes zoomIn { from { opacity: 0; transform: scale(0.8); } to { opacity: 1; transform: scale(1); } }

/* --- Contact Modal --- */
.modal-overlay {
    display: none;
    position: fixed;
    z-index: 3000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(10px);
    justify-content: center;
    align-items: flex-start;
    overflow-y: auto;
    padding: 5vh 20px;
    animation: fadeIn 0.3s ease;
}
.modal-overlay.active { display: flex; }
.modal-content {
    background: #ffffff;
    border: 1px solid var(--border-color);
    padding: 40px;
    border-radius: 20px;
    width: 100%;
    max-width: 700px;
    position: relative;
    box-shadow: 0 10px 40px var(--shadow-color);
    text-align: center;
    animation: slideIn 0.4s ease;
    margin: auto 0;
}
.modal-close { position: absolute; top: 15px; right: 20px; background: none; border: none; color: #000; font-size: 2rem; cursor: pointer; opacity: 0.7; transition: var(--transition-ease); }
.modal-close:hover { opacity: 1; }
.modal-content h3 { font-size: 2rem; margin-bottom: 10px; color: var(--heading-color); }
.modal-subtitle { opacity: 0.8; margin-bottom: 30px; color: var(--text-color); }
.contact-options { display: grid; grid-template-columns: 1fr; gap: 30px; }
.contact-person { background: #f9f9f9; padding: 25px; border-radius: 15px; border: 1px solid var(--border-color); }
.contact-person h4 { font-size: 1.2rem; margin-bottom: 20px; color: var(--primary-color); }
.contact-person h4 i { color: var(--primary-color); margin-right: 10px; }
.contact-link { display: block; text-decoration: none; color: var(--text-color); background: rgba(0,0,0,0.05); padding: 12px; border-radius: 8px; margin-bottom: 10px; transition: var(--transition-ease); font-weight: 500; }
.contact-link:hover { color: #fff; transform: translateY(-3px); background: var(--primary-color); }
.contact-link i { margin-right: 10px; }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes slideIn { from { opacity: 0; transform: translateY(-30px); } to { opacity: 1; transform: translateY(0); } }

/* --- Responsiveness --- */
@media (max-width: 768px) {
    h2 { font-size: 2.2rem; }
    .hero-content h1 { font-size: 2.5rem; }
    .nav-links { display: none; }
    .about-content { flex-direction: column; align-items: center; }
    .contact-options { grid-template-columns: 1fr; }
    .modal-content { padding: 30px 20px; }
}

/* --- GDPR Cookie Consent Banner --- */
.cookie-banner {
    position: fixed;
    bottom: -100%;
    left: 0;
    width: 100%;
    background: #000;
    color: #fff;
    z-index: 4000;
    transition: bottom 0.5s ease-in-out;
    padding: 20px 0;
}
.cookie-banner.show { bottom: 0; }
.cookie-banner-content { max-width: 1100px; margin: 0 auto; padding: 0 20px; display: flex; justify-content: space-between; align-items: center; gap: 20px; }
.cookie-banner p { margin: 0; flex-grow: 1; }
.cookie-banner-actions { display: flex; gap: 15px; flex-shrink: 0; }
.btn-cookie-accept { background: #fff; color: #000; padding: 10px 25px; border-radius: 50px; font-weight: 700; transition: var(--transition-ease); cursor: pointer; }
.btn-cookie-accept:hover { background: #ccc; transform: translateY(-2px); }
.btn-cookie-secondary { background: transparent; color: #fff; padding: 10px 25px; border-radius: 50px; font-weight: 500; border: 1px solid #fff; cursor: pointer; transition: var(--transition-ease); }
.btn-cookie-secondary:hover { background: #fff; color: #000; }

/* --- Cookie Settings Modal --- */
#cookie-settings-modal .modal-content { max-width: 600px; text-align: left; }
.cookie-settings-options { margin: 30px 0; }
.cookie-option { display: flex; justify-content: space-between; align-items: center; padding: 20px 0; border-bottom: 1px solid var(--border-color); }
.cookie-option:last-child { border-bottom: none; }
.cookie-option-text h3 { font-size: 1.1rem; color: var(--heading-color); margin: 0 0 5px; }
.cookie-option-text p { font-size: 0.9rem; opacity: 0.8; margin: 0; line-height: 1.5; }
#cookie-save-settings { width: 100%; }

/* --- Switch Toggle CSS --- */
.switch { position: relative; display: inline-block; width: 50px; height: 28px; flex-shrink: 0; margin-left: 20px; }
.switch input { opacity: 0; width: 0; height: 0; }
.slider { position: absolute; cursor: pointer; top: 0; left: 0; right: 0; bottom: 0; background-color: rgba(255, 255, 255, 0.2); transition: .4s; }
.slider:before { position: absolute; content: ""; height: 20px; width: 20px; left: 4px; bottom: 4px; background-color: white; transition: .4s; }
input:checked + .slider { background-color: var(--primary-color); }
input:disabled + .slider { background-color: #333; cursor: not-allowed; }
input:focus + .slider { box-shadow: 0 0 1px var(--primary-color); }
input:checked + .slider:before { transform: translateX(22px); }
.slider.round { border-radius: 34px; }
.slider.round:before { border-radius: 50%; }

/* --- Responsiveness for Cookie Banner & Modal --- */
@media (max-width: 768px) {
    .cookie-banner-content { flex-direction: column; text-align: center; }
    .cookie-banner p { margin-bottom: 20px; }
}
@media (max-width: 480px) {
    .cookie-banner-actions { flex-direction: column; width: 100%; }
    .cookie-banner-actions button { width: 100%; }
    .cookie-option { flex-direction: column; align-items: flex-start; gap: 15px; }
    .switch { margin-left: 0; }
}