:root {
    --bg-dark: #020617;
    --bg-section: #0b1020;
    --bg-light: #f5f5f7;
    --accent: #f97316;
    --accent-soft: #fed7aa;
    --text-main: #0f172a;
    --text-light: #e5e7eb;
    --text-muted: #6b7280;
    --border-soft: #e5e7eb;
    --max-width: 1120px;
    --radius-lg: 18px;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    color: var(--text-main);
    background-color: white;
    line-height: 1.6;
}

/* Layout helpers */

.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 16px;
}

.section {
    padding: 64px 0;
    background-color: white;
}

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

.section h2 {
    font-size: 1.9rem;
    margin-bottom: 16px;
}

.section-intro {
    max-width: 640px;
}

/* Header */

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background-color: white;
    backdrop-filter: blur(4px);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 0;
}

.logo {
    height: 40px;
    width: auto;
    display: block;
}

.header-tagline {
    font-size: 1rem;
    text-align: right;
}

.text-bright {
    color: #38bdf8;
}

.text-navy {
    color: #172554;
}

.link-bright {
    color: #38bdf8;
    text-decoration: none;
}

/* =======================
   HERO (ปรับให้เนียน)
   ======================= */

.hero {
    position: relative;
    overflow: hidden;
    min-height: 560px;
    padding: 64px 0;
    background-color: var(--bg-dark);
}

/* ภาพพื้นหลัง (ไม่ cover) */
.hero-bg {
    position: absolute;
    inset: 0;
    background-image: url("images/hero-cissp-exam-hackathon.jpg");
    background-size: contain;
    background-repeat: no-repeat;
    background-position: right center;
    background-color: var(--bg-dark);
    z-index: 0;
}

/* overlay โทนเดียว ไม่มีเส้นแบ่ง */
.hero-overlay {
    position: absolute;
    inset: 0;
    z-index: 1;
    pointer-events: none;

    /* สำคัญ: ไม่ทับขวาหนัก ให้ทับเฉพาะฝั่งซ้ายเป็นหลัก */
    background:
        /* ม่านเข้มฝั่งซ้าย (soft edge ไม่มีเส้น) */
        radial-gradient(1200px 900px at 25% 50%,
            rgba(2, 6, 23, 0.92) 0%,
            rgba(2, 6, 23, 0.82) 35%,
            rgba(2, 6, 23, 0.40) 60%,
            rgba(2, 6, 23, 0.10) 78%,
            rgba(2, 6, 23, 0.00) 90%),

        /* glow เบา ๆ แถวๆ คน ให้ภาพมีมิติ */
        radial-gradient(900px 600px at 75% 35%,
            rgba(56, 189, 248, 0.10) 0%,
            rgba(56, 189, 248, 0.00) 60%);
}


.hero-inner {
    position: relative;
    z-index: 2;
    display: grid;
    grid-template-columns: 1.15fr 0.85fr;
    align-items: center;
    gap: 24px;
}

/* ซ้าย: เนื้อหา */
.hero-content {
    max-width: 720px;
    color: #ffffff;
}

.hero h1 {
    font-size: 52px;
    line-height: 1.05;
    letter-spacing: 0.5px;
    margin: 0 0 14px;
    text-transform: uppercase;
}

.hero-subtitle {
    font-size: 18px;
    line-height: 1.6;
    color: rgba(255, 255, 255, .9);
    margin: 0 0 14px;
}

.hero-bullets {
    margin: 0 0 22px;
    padding-left: 18px;
    color: rgba(255, 255, 255, .9);
}

.hero-contact {
    margin-top: 18px;
    padding: 18px;
    border: 1px solid rgba(255, 255, 255, .18);
    border-radius: 14px;
    background: rgba(0, 0, 0, .20);
    backdrop-filter: blur(6px);
}

.hero-contact h2 {
    margin: 0 0 10px;
    font-size: 18px;
}

/* ขวา: รูปผู้สอน */
.hero-person {
    display: flex;
    justify-content: flex-end;
    align-items: flex-end;
}

.hero-person img {
    width: min(420px, 100%);
    height: auto;
    display: block;
    filter: drop-shadow(0 18px 28px rgba(0, 0, 0, .35)) brightness(1.08) contrast(1.05);
    transform: translateY(12px);
}


/* =======================
   HIGHLIGHTS
   ======================= */

.highlights-grid {
    display: grid;
    gap: 20px;
    grid-template-columns: repeat(4, minmax(0, 1fr));
}

.highlight-card {
    padding: 18px 18px 22px;
    border-radius: var(--radius-lg);
    background: #0b1020;
    color: var(--text-light);
    border: 1px solid rgba(148, 163, 184, 0.6);
    transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
    text-align: center;
}

.highlight-icon {
    width: 48px;
    height: 48px;
    margin-bottom: 16px;
    stroke: var(--accent);
    fill: none;
    stroke-width: 1.5;
}

.highlight-card h3 {
    font-size: 1rem;
    margin-top: 0;
}

.highlight-card h3 span {
    display: block;
    font-size: .85rem;
    color: #cbd5f5;
}

.highlight-card p {
    font-size: .9rem;
    color: #e5e7eb;
    margin-top: 0;
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height .4s ease, opacity .4s ease, margin-top .4s ease;
}

.highlight-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 14px 30px rgba(15, 23, 42, .45);
    border-color: var(--accent-soft);
}

.highlight-card:hover p {
    max-height: 100px;
    opacity: 1;
    margin-top: 12px;
}

/* =======================
   AGENDA / BONUS / ETC
   ======================= */

.agenda-grid {
    display: grid;
    gap: 24px;
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.agenda-day {
    background: white;
    border-radius: var(--radius-lg);
    padding: 18px 18px 20px;
    border: 1px solid var(--border-soft);
}

.bonus-grid {
    display: grid;
    gap: 20px;
    grid-template-columns: repeat(4, minmax(0, 1fr));
}

.bonus-item {
    padding: 18px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-soft);
    background: white;
}

/* Instructor */

.instructor {
    display: grid;
    gap: 32px;
    grid-template-columns: minmax(0, 320px) minmax(0, 1fr);
    align-items: center;
}

.instructor-photo img {
    width: 100%;
    border-radius: 24px;
    object-fit: cover;
}

/* ทำให้รูปคลิกได้อย่างเป็นธรรมชาติ */
.instructor-photo a {
    display: block;
}

/* hover เบา ๆ ดู professional ไม่ flashy */
.instructor-photo a:hover img {
    transform: translateY(-2px);
    box-shadow: 0 12px 26px rgba(15, 23, 42, 0.25);
    transition: transform 0.15s ease, box-shadow 0.15s ease;
}

/* กัน animation กระตุกตอนโหลด */
.instructor-photo img {
    transition: transform 0.15s ease, box-shadow 0.15s ease;
}

/* Final CTA */

.final-cta {
    background: var(--bg-dark);
    color: var(--text-light);
    text-align: center;
}

/* =======================
   RESPONSIVE
   ======================= */

@media (max-width: 900px) {
    .hero-inner {
        grid-template-columns: 1fr;
    }

    .hero h1 {
        font-size: 40px;
    }

    .highlights-grid,
    .bonus-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .hero-content {
        padding: 48px 0;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .highlights-grid,
    .bonus-grid,
    .agenda-grid,
    .instructor {
        grid-template-columns: 1fr;
    }

    .site-header {
        position: static;
    }
}