@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans+Thai:wght@300;400;500;600;700&family=Manrope:wght@400;500;600;700;800&display=swap');

:root {
    --navy: #10243e;
    --navy-deep: #091728;
    --ink: #152031;
    --muted: #667085;
    --paper: #f4f1ea;
    --white: #ffffff;
    --accent: #e6a94b;
    --accent-soft: #f3d8a7;
    --line: rgba(16, 36, 62, .14);
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 76px;
}

body {
    margin: 0;
    color: var(--ink);
    background: var(--paper);
    font-family: "IBM Plex Sans Thai", "Manrope", sans-serif;
    font-size: 1rem;
    line-height: 1.75;
    -webkit-font-smoothing: antialiased;
}

.skip-link {
    position: fixed;
    top: -80px;
    left: 1rem;
    z-index: 2000;
    padding: .75rem 1rem;
    color: var(--navy);
    background: var(--white);
    transition: top .2s ease;
}

.skip-link:focus { top: 1rem; }

.navbar {
    padding: 1rem 0;
    background: rgba(9, 23, 40, .2);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(255, 255, 255, .08);
    transition: padding .25s ease, background .25s ease;
}

.navbar.scrolled {
    padding: .6rem 0;
    background: rgba(9, 23, 40, .96);
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: .7rem;
    font-family: "Manrope", sans-serif;
    font-size: .9rem;
    font-weight: 800;
    letter-spacing: .16em;
}

.brand-mark {
    display: grid;
    width: 2.2rem;
    height: 2.2rem;
    place-items: center;
    color: var(--navy-deep);
    background: var(--accent);
    border-radius: 50%;
    letter-spacing: -.04em;
}

.navbar .nav-link {
    margin-left: 1.4rem;
    color: rgba(255,255,255,.75);
    font-weight: 500;
}

.navbar .nav-link:hover,
.navbar .nav-link:focus { color: var(--white); }

.navbar .nav-contact {
    padding-inline: 1.15rem !important;
    border: 1px solid rgba(255,255,255,.4);
    border-radius: 999px;
}

.hero {
    position: relative;
    overflow: hidden;
    color: var(--white);
    background:
        radial-gradient(circle at 83% 25%, rgba(230,169,75,.22), transparent 24%),
        linear-gradient(120deg, var(--navy-deep), var(--navy));
}

.hero::before {
    position: absolute;
    top: 8%;
    right: -8vw;
    width: 48vw;
    height: 48vw;
    content: "";
    border: 1px solid rgba(255,255,255,.12);
    border-radius: 50%;
    box-shadow:
        0 0 0 7vw rgba(255,255,255,.025),
        0 0 0 14vw rgba(255,255,255,.018);
}

.hero-grid {
    position: absolute;
    inset: 0;
    opacity: .12;
    background-image:
        linear-gradient(rgba(255,255,255,.18) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,.18) 1px, transparent 1px);
    background-size: 72px 72px;
    mask-image: linear-gradient(to right, black, transparent 75%);
}

.eyebrow,
.section-kicker {
    color: var(--accent);
    font-family: "Manrope", sans-serif;
    font-size: .75rem;
    font-weight: 800;
    letter-spacing: .22em;
}

.display-title {
    max-width: 950px;
    font-size: clamp(3rem, 7vw, 6.7rem);
    font-weight: 300;
    line-height: .98;
    letter-spacing: -.055em;
}

.display-name {
    display: inline-block;
    font-size: clamp(2.35rem, 5vw, 4.75rem);
}

.display-title span { font-weight: 700; }

.hero-subtitle {
    max-width: 780px;
    color: rgba(255,255,255,.72);
    font-size: clamp(1.1rem, 2vw, 1.45rem);
}

.btn {
    padding: .8rem 1.5rem;
    border-radius: 999px;
    font-weight: 600;
}

.btn-accent {
    color: var(--navy-deep);
    background: var(--accent);
    border-color: var(--accent);
}

.btn-accent:hover,
.btn-accent:focus {
    color: var(--navy-deep);
    background: #f0bd68;
    border-color: #f0bd68;
}

.hero-card {
    display: flex;
    aspect-ratio: 1;
    max-width: 330px;
    margin-left: auto;
    padding: 2.2rem;
    flex-direction: column;
    justify-content: flex-end;
    background: rgba(255,255,255,.07);
    border: 1px solid rgba(255,255,255,.15);
    border-radius: 50%;
    backdrop-filter: blur(8px);
}

.hero-card-number {
    color: var(--accent);
    font-family: "Manrope", sans-serif;
    font-size: 4.8rem;
    font-weight: 700;
    line-height: 1;
}

.hero-card-label {
    color: rgba(255,255,255,.76);
    font-size: 1rem;
    line-height: 1.5;
}

.scroll-cue {
    position: absolute;
    bottom: 1.5rem;
    left: 50%;
    display: grid;
    width: 2rem;
    height: 3.2rem;
    place-items: start center;
    border: 1px solid rgba(255,255,255,.35);
    border-radius: 999px;
    transform: translateX(-50%);
}

.scroll-cue span {
    width: 4px;
    height: 8px;
    margin-top: .55rem;
    background: var(--accent);
    border-radius: 99px;
    animation: scroll-cue 1.8s infinite;
}

@keyframes scroll-cue {
    0% { opacity: 0; transform: translateY(0); }
    30% { opacity: 1; }
    100% { opacity: 0; transform: translateY(14px); }
}

.section { padding: clamp(5rem, 10vw, 9rem) 0; }

.section-title {
    margin: 0;
    font-size: clamp(2.3rem, 5vw, 4.2rem);
    font-weight: 600;
    line-height: 1.13;
    letter-spacing: -.045em;
}

.title-rule {
    width: 4rem;
    height: 3px;
    margin-top: 2rem;
    background: var(--accent);
}

.lead-copy {
    max-width: 900px;
    font-size: clamp(1.25rem, 2.4vw, 1.75rem);
    font-weight: 400;
    line-height: 1.55;
}

.body-copy {
    max-width: 850px;
    color: var(--muted);
    font-family: "Manrope", "IBM Plex Sans Thai", sans-serif;
    font-size: 1rem;
}

.expertise-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    border-top: 1px solid var(--line);
    border-left: 1px solid var(--line);
}

.expertise-grid div {
    min-height: 130px;
    padding: 1.5rem;
    border-right: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.expertise-grid span {
    display: block;
    margin-bottom: 1.3rem;
    color: var(--accent);
    font-family: "Manrope", sans-serif;
    font-size: .72rem;
    font-weight: 800;
}

.expertise-grid strong {
    font-family: "Manrope", sans-serif;
    font-size: .95rem;
}

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

.section-intro { color: rgba(255,255,255,.6); }

.education-list { border-top: 1px solid rgba(255,255,255,.18); }

.education-item {
    display: grid;
    padding: 2rem 0;
    grid-template-columns: 80px minmax(0, 1.25fr) minmax(0, 1fr);
    gap: 1.5rem;
    align-items: center;
    border-bottom: 1px solid rgba(255,255,255,.18);
    transition: padding-inline .25s ease, background .25s ease;
}

.education-item:hover {
    padding-inline: 1.2rem;
    background: rgba(255,255,255,.035);
}

.item-number {
    color: var(--accent);
    font-family: "Manrope", sans-serif;
    font-size: .75rem;
    font-weight: 800;
}

.education-item h3 {
    margin: 0;
    font-size: clamp(1.15rem, 2.3vw, 1.65rem);
    font-weight: 500;
}

.education-item p {
    margin: 0;
    color: rgba(255,255,255,.58);
    font-family: "Manrope", "IBM Plex Sans Thai", sans-serif;
}

.publication-section { background: #fff; }

.publication-card {
    position: relative;
    display: flex;
    min-height: 280px;
    overflow: hidden;
    padding: 1.8rem;
    flex-direction: column;
    background: var(--paper);
    border: 1px solid transparent;
    transition: transform .25s ease, border-color .25s ease, box-shadow .25s ease;
}

.publication-card::after {
    position: absolute;
    right: -2.3rem;
    bottom: -2.3rem;
    width: 7rem;
    height: 7rem;
    content: "";
    background: var(--accent-soft);
    border-radius: 50%;
    transition: transform .3s ease;
}

.publication-card:hover {
    z-index: 1;
    border-color: var(--accent);
    box-shadow: 0 18px 40px rgba(16,36,62,.11);
    transform: translateY(-6px);
}

.publication-card:hover::after { transform: scale(1.25); }

.publication-topline {
    display: flex;
    margin-bottom: 3rem;
    justify-content: space-between;
    color: var(--muted);
    font-family: "Manrope", sans-serif;
    font-size: .75rem;
    font-weight: 700;
}

.publication-card h3 {
    position: relative;
    z-index: 1;
    margin-bottom: 1.5rem;
    font-size: 1.35rem;
    font-weight: 600;
    line-height: 1.5;
}

.publication-card p {
    position: relative;
    z-index: 1;
    margin: auto 0 0;
    color: var(--muted);
    font-family: "Manrope", sans-serif;
    font-size: .78rem;
}

.contact-section {
    padding: 2rem 0 7rem;
    color: var(--white);
    background: #fff;
}

.contact-panel {
    display: grid;
    padding: clamp(2rem, 6vw, 5rem);
    grid-template-columns: 1.45fr .75fr;
    gap: 3rem;
    align-items: end;
    background: var(--navy);
}

.contact-panel h2 {
    margin: 0;
    font-size: clamp(2rem, 5vw, 4rem);
    font-weight: 500;
    line-height: 1.18;
}

.contact-meta {
    color: rgba(255,255,255,.68);
    border-left: 2px solid var(--accent);
    padding-left: 1.5rem;
}

.contact-meta p { margin: .35rem 0; }

footer {
    padding: 1.7rem 0;
    color: rgba(255,255,255,.52);
    background: var(--navy-deep);
    font-family: "Manrope", sans-serif;
    font-size: .75rem;
}

footer p { margin: 0; }

@media (max-width: 991.98px) {
    .navbar-collapse {
        margin-top: 1rem;
        padding: 1rem;
        background: var(--navy-deep);
        border-radius: .5rem;
    }

    .navbar .nav-link { margin-left: 0; }
    .navbar .nav-contact { display: inline-block; margin-top: .5rem; }

    .education-item {
        grid-template-columns: 48px 1fr;
    }

    .education-item p {
        grid-column: 2;
    }
}

@media (max-width: 767.98px) {
    .display-title { font-size: clamp(2.7rem, 13vw, 4rem); }
    .hero-subtitle br { display: none; }
    .expertise-grid { grid-template-columns: 1fr; }
    .contact-panel { grid-template-columns: 1fr; }
    .contact-meta { margin-top: 1rem; }
}

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after {
        animation-duration: .01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: .01ms !important;
    }
}