/* ==============================================
   mirAI塾 ランディングページ - スタイルシート
   ============================================== */

/* Variables */
:root {
    --color-white: #ffffff;
    --color-blue-main: #1d5a9f;
    --color-blue-dark: #0d3d6f;
    --color-orange: #ea5d08;
    --color-dark-gray: #222222;
    --color-gray: #333333;
    --color-light-gray: #f8f9fa;
    --font-main: 'Noto Sans JP', sans-serif;
}

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-main);
    color: var(--color-dark-gray);
    line-height: 1.8;
    background-color: var(--color-white);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ==============================================
   Header
   ============================================== */
.header {
    background-color: var(--color-white);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
    transition: box-shadow 0.3s ease;
}

.header.scrolled {
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.header-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 15px 20px;
    max-width: 1200px;
    margin: 0 auto;
}

.header-logo img {
    height: 60px;
    width: auto;
}

.header-nav {
    flex: 1;
    display: flex;
    justify-content: center;
}

.nav-list {
    display: flex;
    list-style: none;
    gap: 40px;
}

.nav-list a {
    text-decoration: none;
    color: var(--color-dark-gray);
    font-weight: 500;
    font-size: 16px;
    transition: color 0.3s ease;
}

.nav-list a:hover {
    color: var(--color-blue-main);
}

.header-cta-btn {
    background-color: var(--color-orange);
    color: var(--color-white);
    padding: 12px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    font-size: 16px;
    transition: all 0.3s ease;
    white-space: nowrap;
}

.header-cta-btn:hover {
    background-color: #d34f00;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(234, 93, 8, 0.3);
}

/* Hamburger Menu */
.hamburger {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: var(--color-dark-gray);
    margin: 3px 0;
    transition: 0.3s;
    border-radius: 2px;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(-45deg) translate(-5px, 6px);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
}

.hamburger.active span:nth-child(3) {
    transform: rotate(45deg) translate(-5px, -6px);
}

.mobile-menu {
    display: none;
    background-color: var(--color-white);
    border-top: 1px solid #e0e0e0;
}

.mobile-menu.active {
    display: block;
}

.mobile-menu ul {
    list-style: none;
    padding: 20px;
}

.mobile-menu ul li {
    margin-bottom: 15px;
}

.mobile-menu ul li a {
    text-decoration: none;
    color: var(--color-dark-gray);
    font-weight: 500;
    font-size: 16px;
    display: block;
    padding: 10px;
    transition: color 0.3s ease;
}

.mobile-menu ul li a:hover {
    color: var(--color-orange);
}

/* ==============================================
   Hero Section
   ============================================== */
.hero {
    position: relative;
    background: linear-gradient(135deg, #0a2540 0%, var(--color-blue-dark) 50%, var(--color-blue-main) 100%);
    color: var(--color-white);
    padding: 100px 20px 80px;
    text-align: center;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(234, 93, 8, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(29, 90, 159, 0.2) 0%, transparent 50%);
    animation: pulseBackground 10s ease-in-out infinite;
}

@keyframes pulseBackground {
    0%, 100% { opacity: 0.6; }
    50% { opacity: 1; }
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg, transparent 0%, rgba(0, 0, 0, 0.2) 100%);
}

.hero-content {
    position: relative;
    z-index: 10;
}

.hero-badge {
    display: inline-block;
    background: linear-gradient(135deg, var(--color-orange) 0%, #ff7b00 100%);
    color: var(--color-white);
    padding: 12px 30px;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 30px;
    box-shadow: 0 4px 15px rgba(234, 93, 8, 0.4);
    animation: badge-pulse 2s ease-in-out infinite;
}

@keyframes badge-pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.hero-title {
    font-size: 48px;
    font-weight: 900;
    margin-bottom: 25px;
    line-height: 1.4;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.hero-title-main {
    display: block;
    margin-bottom: 10px;
}

.hero-title-emphasis {
    display: block;
    background: linear-gradient(135deg, #ffffff 0%, var(--color-orange) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-size: 52px;
}

.hero-subtitle {
    font-size: 22px;
    font-weight: 500;
    margin-bottom: 50px;
    line-height: 1.8;
    text-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

.hero-subtitle strong {
    color: var(--color-orange);
    font-weight: 700;
}

.event-info {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin-bottom: 50px;
    flex-wrap: wrap;
}

.event-detail {
    display: flex;
    align-items: center;
    gap: 15px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 15px;
    padding: 20px 30px;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: all 0.3s ease;
}

.event-detail:hover {
    background-color: rgba(255, 255, 255, 0.15);
    transform: translateY(-5px);
}

.event-icon-box {
    background-color: var(--color-orange);
    color: var(--color-white);
    font-size: 16px;
    font-weight: 700;
    padding: 10px 15px;
    border-radius: 8px;
    min-width: 60px;
    text-align: center;
}

.event-label {
    font-size: 14px;
    font-weight: 500;
    opacity: 0.8;
    margin-bottom: 5px;
}

.event-value {
    font-size: 20px;
    font-weight: 700;
}

.cta-button-hero {
    font-size: 20px;
    padding: 20px 60px;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    animation: cta-pulse 2s ease-in-out infinite;
}

@keyframes cta-pulse {
    0%, 100% { box-shadow: 0 4px 15px rgba(234, 93, 8, 0.3); }
    50% { box-shadow: 0 6px 25px rgba(234, 93, 8, 0.5); }
}

.cta-button-arrow {
    font-size: 24px;
    transition: transform 0.3s ease;
}

.cta-button-hero:hover .cta-button-arrow {
    transform: translateX(5px);
}

.hero-note {
    margin-top: 20px;
    font-size: 16px;
    opacity: 0.9;
    font-weight: 500;
}

/* ==============================================
   Sections
   ============================================== */
.section {
    padding: 80px 20px;
}

.section-white {
    background-color: var(--color-white);
}

.section-blue {
    background-color: var(--color-blue-dark);
    color: var(--color-white);
}

.section-title {
    font-size: 32px;
    font-weight: 900;
    margin-bottom: 40px;
    text-align: center;
    line-height: 1.5;
}

.section-white .section-title {
    color: var(--color-blue-main);
}

.section-content {
    max-width: 900px;
    margin: 0 auto;
}

.section-content p {
    font-size: 22px;
    line-height: 2;
    margin-bottom: 30px;
}

.intro-text {
    font-size: 23px;
    font-weight: 500;
    margin-bottom: 35px;
    line-height: 2;
}

.intro-emphasis {
    font-size: 28px;
    font-weight: 700;
    color: var(--color-white);
    margin-bottom: 20px;
    text-align: center;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.15) 0%, rgba(255, 255, 255, 0.05) 100%);
    padding: 20px;
    border-radius: 10px;
    border: 2px solid rgba(255, 255, 255, 0.3);
}

.subsection-title {
    font-size: 28px;
    font-weight: 700;
    color: var(--color-orange);
    margin-bottom: 20px;
}

.subsection-title strong {
    font-size: 30px;
}

/* Visual Box */
.visual-box {
    background-color: var(--color-light-gray);
    border-radius: 15px;
    padding: 40px;
    text-align: center;
    margin-top: 40px;
}

.section-blue .visual-box {
    background-color: rgba(255, 255, 255, 0.1);
}

.visual-box-highlight {
    background: linear-gradient(135deg, var(--color-orange) 0%, #ff7b00 100%);
    color: var(--color-white);
    padding: 50px;
    box-shadow: 0 10px 30px rgba(234, 93, 8, 0.4);
    border: 3px solid rgba(255, 255, 255, 0.3);
    transform: scale(1.02);
}

.visual-badge {
    display: inline-block;
    background-color: var(--color-white);
    color: var(--color-orange);
    padding: 15px 35px;
    border-radius: 50px;
    font-size: 24px;
    font-weight: 900;
    margin-bottom: 30px;
    border: 3px solid var(--color-white);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    text-transform: none;
    letter-spacing: 0.5px;
}

.visual-stats {
    margin-top: 20px;
}

.visual-stats-label {
    font-size: 24px;
    font-weight: 500;
    display: block;
    margin-bottom: 15px;
}

.visual-stats-value {
    font-size: 48px;
    font-weight: 900;
    display: block;
    color: var(--color-white);
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.visual-text {
    font-size: 22px;
    font-weight: 700;
    color: var(--color-blue-main);
}

.section-blue .visual-text {
    color: var(--color-white);
}

/* Text Highlight */
.text-highlight {
    color: var(--color-orange);
    font-weight: 700;
    background: linear-gradient(transparent 60%, rgba(234, 93, 8, 0.2) 60%);
    padding: 0 4px;
}

.section-blue .text-highlight {
    color: var(--color-orange);
    background: linear-gradient(transparent 60%, rgba(234, 93, 8, 0.3) 60%);
}

/* Text Highlight for white background (challenges list) */
.challenges-list .text-highlight {
    color: var(--color-orange);
    font-weight: 900;
    background: none;
    padding: 0;
}

/* Stronger Text Highlight (for special emphasis like subsidy info) */
.text-highlight-strong {
    color: var(--color-white);
    font-weight: 900;
    background-color: var(--color-orange);
    padding: 4px 10px;
    border-radius: 5px;
    display: inline-block;
    box-shadow: 0 2px 8px rgba(234, 93, 8, 0.4);
}

/* Visual Box Updates */
.visual-subtext {
    font-size: 20px;
    margin-top: 15px;
    opacity: 0.9;
}

.visual-subtext strong {
    color: var(--color-orange);
    font-size: 24px;
}

/* Challenges List */
.challenges-list {
    list-style: none;
    margin-top: 30px;
}

.challenges-list li {
    display: flex;
    align-items: flex-start;
    margin-bottom: 25px;
    padding: 25px;
    background-color: var(--color-white);
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.challenges-list li:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

.challenge-number {
    background: linear-gradient(135deg, var(--color-blue-main) 0%, var(--color-blue-dark) 100%);
    color: var(--color-white);
    font-size: 18px;
    font-weight: 900;
    padding: 10px 18px;
    border-radius: 10px;
    margin-right: 20px;
    flex-shrink: 0;
    min-width: 55px;
    text-align: center;
    box-shadow: 0 2px 8px rgba(29, 90, 159, 0.3);
}

.challenges-list p {
    font-size: 19px;
    line-height: 1.9;
    margin: 0;
    color: var(--color-dark-gray);
}

/* Demo Grid */
.demo-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.demo-card {
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 15px;
    padding: 30px;
    text-align: center;
    transition: transform 0.3s ease, background-color 0.3s ease, box-shadow 0.3s ease;
}

.demo-card:hover {
    transform: translateY(-10px);
    background-color: rgba(255, 255, 255, 0.15);
}

.demo-card-enhanced {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.15) 0%, rgba(255, 255, 255, 0.08) 100%);
    border: 2px solid rgba(255, 255, 255, 0.2);
    padding: 40px;
}

.demo-card-enhanced:hover {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.2) 0%, rgba(255, 255, 255, 0.12) 100%);
    border-color: rgba(255, 255, 255, 0.4);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.3);
}

.demo-icon {
    font-size: 50px;
    margin-bottom: 20px;
}

.demo-icon-large {
    font-size: 70px;
    margin-bottom: 25px;
}

.demo-title {
    font-size: 20px;
    font-weight: 700;
    color: var(--color-orange);
    margin-bottom: 15px;
}

.demo-title-large {
    font-size: 26px;
    margin-bottom: 20px;
    color: var(--color-white);
    background: linear-gradient(135deg, var(--color-orange) 0%, #ffb347 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.demo-card p {
    font-size: 16px;
    line-height: 1.7;
    margin: 0;
}

.demo-text-large {
    font-size: 22px;
    line-height: 2;
    font-weight: 600;
}

/* ==============================================
   CTA Sections
   ============================================== */
.cta-button {
    display: inline-block;
    background-color: var(--color-orange);
    color: var(--color-white);
    padding: 18px 50px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    font-size: 18px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(234, 93, 8, 0.3);
}

.cta-button:hover {
    background-color: #d34f00;
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(234, 93, 8, 0.4);
}

.cta-button-large {
    padding: 22px 60px;
    font-size: 20px;
}

/* White CTA Button for Orange Background */
.cta-button-white {
    background-color: var(--color-white);
    color: var(--color-orange);
    box-shadow: 0 4px 15px rgba(255, 255, 255, 0.3);
}

.cta-button-white:hover {
    background-color: #f5f5f5;
    color: #d34f00;
    box-shadow: 0 6px 20px rgba(255, 255, 255, 0.4);
}

.cta-section {
    background: linear-gradient(135deg, var(--color-orange) 0%, #d34f00 100%);
    color: var(--color-white);
    padding: 60px 20px;
    text-align: center;
}

.cta-text {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 30px;
}

.cta-final {
    background: linear-gradient(135deg, var(--color-blue-main) 0%, var(--color-blue-dark) 100%);
    padding: 80px 20px;
}

.cta-final-title {
    font-size: 32px;
    font-weight: 900;
    margin-bottom: 20px;
}

/* ==============================================
   Seminar Details Section
   ============================================== */
.section-details {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    padding: 80px 20px;
}

.section-title-details {
    color: var(--color-blue-main);
    font-size: 36px;
    margin-bottom: 50px;
}

.details-content {
    max-width: 1000px;
    margin: 0 auto;
}

.details-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.detail-item {
    background-color: var(--color-white);
    border-radius: 15px;
    padding: 30px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border-left: 5px solid var(--color-blue-main);
}

.detail-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.12);
}

.detail-item-important {
    border: 3px solid var(--color-orange);
    border-left: 5px solid var(--color-orange);
    background: linear-gradient(135deg, #fff5f0 0%, var(--color-white) 100%);
}

.detail-info {
    width: 100%;
}

.detail-label {
    font-size: 16px;
    font-weight: 700;
    color: var(--color-blue-main);
    margin-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.detail-value {
    font-size: 20px;
    font-weight: 500;
    color: var(--color-dark-gray);
    line-height: 1.6;
}

.detail-value strong {
    color: var(--color-orange);
    font-weight: 900;
}

.detail-value-highlight {
    color: var(--color-orange);
    font-size: 28px;
    font-weight: 900;
}

/* ==============================================
   Instructors Section
   ============================================== */
.instructors-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 40px;
    margin-top: 50px;
}

.instructor-card {
    background-color: var(--color-light-gray);
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.instructor-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

.instructor-image {
    position: relative;
    width: 100%;
    height: 350px;
    overflow: hidden;
}

.instructor-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.instructor-image .company-logo {
    position: absolute;
    bottom: 15px;
    right: 15px;
    width: 80px;
    height: auto;
    background-color: var(--color-white);
    padding: 8px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.instructor-info {
    padding: 30px;
}

.instructor-name {
    font-size: 24px;
    font-weight: 700;
    color: var(--color-blue-main);
    margin-bottom: 8px;
}

.instructor-title {
    font-size: 16px;
    font-weight: 500;
    color: var(--color-gray);
    margin-bottom: 20px;
}

.instructor-credentials {
    margin-bottom: 20px;
    padding-bottom: 20px;
    border-bottom: 2px solid #e0e0e0;
}

.instructor-credentials p {
    font-size: 16px;
    line-height: 1.9;
    color: var(--color-gray);
    margin-bottom: 5px;
}

.instructor-bio p {
    font-size: 17px;
    line-height: 1.9;
    color: var(--color-dark-gray);
    margin-bottom: 12px;
}

.instructor-achievements {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 2px solid #e0e0e0;
}

.instructor-achievements h4 {
    font-size: 20px;
    font-weight: 700;
    color: var(--color-orange);
    margin-bottom: 15px;
}

.instructor-achievements p {
    font-size: 17px;
    line-height: 1.9;
    color: var(--color-dark-gray);
    margin-bottom: 10px;
}

/* ==============================================
   Footer
   ============================================== */
.footer {
    background-color: var(--color-dark-gray);
    color: var(--color-white);
    padding: 40px 20px;
    text-align: center;
}

.footer-note {
    font-size: 16px;
    line-height: 1.9;
    opacity: 0.9;
    margin-bottom: 25px;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.footer-copyright {
    font-size: 15px;
    opacity: 0.8;
}

/* ==============================================
   Responsive Design
   ============================================== */

/* Tablet */
@media (max-width: 1023px) {
    .hero-title {
        font-size: 34px;
    }

    .hero-subtitle {
        font-size: 18px;
    }

    .section-title {
        font-size: 28px;
    }

    .instructors-grid {
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    }

    .details-grid {
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    }
}

/* Mobile */
@media (max-width: 768px) {
    .header-nav,
    .header-cta-btn {
        display: none;
    }

    .hamburger {
        display: flex;
    }

    .hero {
        padding: 80px 20px 60px;
    }

    .hero-title {
        font-size: 26px;
        line-height: 1.5;
    }

    .hero-title-main {
        display: block;
        margin-bottom: 8px;
        font-size: 26px;
    }

    .hero-title-emphasis {
        font-size: 30px;
        margin-top: 0;
    }

    .hero-subtitle {
        font-size: 16px;
    }

    .event-info {
        flex-direction: column;
        gap: 20px;
    }

    .event-detail {
        padding: 15px 25px;
    }

    .event-value {
        font-size: 16px;
    }

    .cta-button-hero {
        font-size: 18px;
        padding: 18px 50px;
    }

    .section {
        padding: 60px 20px;
    }

    .section-title {
        font-size: 24px;
    }

    .section-content p {
        font-size: 18px;
    }

    .intro-text {
        font-size: 19px;
    }

    .intro-emphasis {
        font-size: 22px;
        padding: 15px;
    }

    .challenges-list li {
        padding: 20px;
    }

    .challenge-number {
        font-size: 16px;
        padding: 8px 14px;
        min-width: 50px;
        margin-right: 15px;
    }

    .challenges-list p {
        font-size: 17px;
    }

    .demo-text-large {
        font-size: 19px;
    }

    .visual-badge {
        font-size: 20px;
        padding: 12px 25px;
    }

    .visual-stats-label {
        font-size: 20px;
    }

    .visual-stats-value {
        font-size: 40px;
    }

    .details-grid {
        grid-template-columns: 1fr;
    }

    .detail-item {
        padding: 20px;
    }

    .detail-value {
        font-size: 18px;
    }

    .detail-value-highlight {
        font-size: 24px;
    }

    .demo-grid {
        grid-template-columns: 1fr;
    }

    .instructors-grid {
        grid-template-columns: 1fr;
    }

    .instructor-image {
        height: 300px;
    }

    .cta-button {
        padding: 16px 40px;
        font-size: 16px;
    }

    .cta-button-large {
        padding: 18px 50px;
        font-size: 18px;
    }

    .stats-grid {
        grid-template-columns: 1fr;
    }
}

/* Small Mobile */
@media (max-width: 480px) {
    .header-logo img {
        height: 50px;
    }

    .hero-title {
        font-size: 22px;
        line-height: 1.5;
    }

    .hero-title-main {
        margin-bottom: 8px;
        font-size: 22px;
    }

    .hero-title-emphasis {
        font-size: 26px;
        margin-top: 0;
    }

    .hero-subtitle {
        font-size: 14px;
    }

    .hero-badge {
        font-size: 12px;
        padding: 8px 20px;
    }

    .cta-button-hero {
        font-size: 16px;
        padding: 16px 40px;
    }

    .section-title {
        font-size: 20px;
    }

    .cta-final-title {
        font-size: 24px;
    }
}

/* ==============================================
   Animations
   ============================================== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.8s ease-out forwards;
}

.section-content,
.demo-card,
.instructor-card,
.challenges-list li {
    opacity: 0;
    animation: fadeIn 0.8s ease-out forwards;
}

.section-content {
    animation-delay: 0.2s;
}

.demo-card:nth-child(1) {
    animation-delay: 0.3s;
}

.demo-card:nth-child(2) {
    animation-delay: 0.4s;
}

.demo-card:nth-child(3) {
    animation-delay: 0.5s;
}

.instructor-card:nth-child(1) {
    animation-delay: 0.3s;
}

.instructor-card:nth-child(2) {
    animation-delay: 0.4s;
}

.instructor-card:nth-child(3) {
    animation-delay: 0.5s;
}