:root {
    --navy: #003568;
    --blue: #1889bf;
    --teal: #00a8a0;
    --green: #20bd5b;
    --line: #d8e4ec;
    --muted: #6d7d8e;
}

* { box-sizing: border-box; }

html, body, form { width: 100%; min-height: 100%; margin: 0; }

body {
    min-height: 100vh;
    background: #edf3f6;
    color: var(--navy);
    font-family: Tahoma, "Noto Sans Thai", Arial, sans-serif;
}

.portal-shell {
    display: grid;
    grid-template-columns: 58% 42%;
    width: 100%;
    min-height: 100vh;
    overflow: hidden;
    background: #fff;
}

.hero {
    position: relative;
    min-height: 100vh;
    overflow: hidden;
    background: linear-gradient(135deg, #d9f5fa 0%, #71c1dc 52%, #0877aa 100%);
}

.brand {
    position: absolute;
    z-index: 5;
    top: 6.5%;
    left: 5.5%;
    display: flex;
    align-items: center;
    gap: 14px;
    color: #fff;
}

.brand-icon {
    display: grid;
    place-items: center;
    width: 42px;
    height: 42px;
    border-radius: 11px;
    background: var(--teal);
    font: 700 31px/1 Arial, sans-serif;
}

.brand h1 { margin: 0; font-size: clamp(18px, 1.4vw, 28px); }
.brand p { margin: 5px 0 0; color: rgba(255,255,255,.72); font-size: 12px; }

.shape { position: absolute; background: linear-gradient(145deg, #07547f, #006aa2); }
.shape-circle { top: -4%; right: 8%; width: 23vw; height: 23vw; border-radius: 50%; box-shadow: 0 3px 9px rgba(0,48,89,.32); }
.shape-block { left: -10%; bottom: 34%; width: 50%; height: 39%; border-radius: 50% 50% 0 0; transform: rotate(-10deg); }
.green-line { position: absolute; left: 0; right: 0; bottom: 31%; height: 22px; background: repeating-linear-gradient(135deg, #24c660 0 42px, #08ad80 42px 84px); }
.stripe-floor { position: absolute; left: 0; right: 0; bottom: 0; height: 31%; background: repeating-linear-gradient(154deg, #00436f 0 29px, #188fc5 30px 35px, #00436f 36px 66px); }

.system-picker { display: grid; place-items: center; padding: 48px; background: #fff; }
.picker-content { width: min(100%, 470px); }
.eyebrow { margin: 0 0 10px; color: #008c77; font-weight: 700; }
.system-picker h2 { margin: 0; font-size: clamp(34px, 3vw, 50px); letter-spacing: -.5px; }
.intro { margin: 10px 0 30px; color: var(--muted); }

.system-card {
    display: flex;
    align-items: center;
    width: 100%;
    min-height: 92px;
    margin-top: 16px;
    padding: 17px 20px;
    border: 1px solid var(--line);
    border-radius: 14px;
    color: var(--navy);
    text-decoration: none;
    box-shadow: 0 7px 20px rgba(0,48,89,.06);
    transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
}

.system-card:hover, .system-card:focus-visible { transform: translateY(-2px); border-color: var(--green); box-shadow: 0 10px 25px rgba(0,90,100,.14); outline: none; }
.card-icon { display: grid; place-items: center; flex: 0 0 52px; height: 52px; border-radius: 12px; background: linear-gradient(145deg, var(--teal), #087fa9); color: #fff; font-weight: 700; }
.card-copy { display: flex; flex: 1; flex-direction: column; gap: 5px; padding: 0 16px; }
.card-copy strong { font-size: 18px; }
.card-copy small { color: var(--muted); }
.arrow { color: var(--green); font-size: 27px; font-weight: 700; }

@media (max-width: 850px) {
    .portal-shell { grid-template-columns: 1fr; }
    .hero { min-height: 260px; }
    .shape-circle { width: 180px; height: 180px; }
    .shape-block { bottom: 29%; }
    .green-line { bottom: 25%; height: 13px; }
    .stripe-floor { height: 25%; }
    .system-picker { padding: 42px 22px 55px; }
}

@media (max-width: 480px) {
    .brand { top: 30px; left: 25px; }
    .brand-icon { width: 38px; height: 38px; }
    .system-card { padding: 14px; }
    .card-copy strong { font-size: 16px; }
}