/* Reset */
* {
    box-sizing: border-box;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
      "Noto Sans TC", sans-serif;
}

html, body {
    height: 100%;
    margin: 0;
}

/* Background image */
body {
    background: url("./images/bg.jpg") center / cover
      no-repeat;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #ffffff;
    position: relative;
}

/* Dark overlay + grayscale */
.overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.65);
    backdrop-filter: grayscale(100%);
}

/* Language switch */
.lang-switch {
    position: absolute;
    top: 24px;
    right: 32px;
    z-index: 2;
    font-size: 0.95rem;
}

.lang-switch button {
    background: none;
    border: none;
    color: #ffffff;
    cursor: pointer;
    font-weight: 600;
}

.lang-switch span {
    margin: 0 6px;
    opacity: 0.6;
}

/* Content container */
.container {
    position: relative;
    z-index: 2;
    text-align: center;
    max-width: 640px;
    padding: 32px;
}

/* Logo */
.logo {
    width: 220px;
    margin-bottom: 24px;
}

/* Headline */
h1 {
    font-size: 2.4rem;
    margin-bottom: 16px;
    letter-spacing: 0.5px;
}

/* Message text */
p {
    font-size: 1.25rem;
    line-height: 1.8;
    opacity: 0.95;
    margin-bottom: 32px;
}

/* CTA button — GEOS green */
.cta {
    cursor: pointer;
    display: inline-block;
    padding: 16px 34px;
    border-radius: 999px;
    font-size: 1.1rem;
    font-weight: 700;
    text-decoration: none;
    color: #ffffff;
    background: linear-gradient(135deg, #00b3a4, #16e0c2);
    box-shadow: 0 12px 30px rgba(0, 179, 164, 0.45);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    }

.cta:hover {
    transform: translateY(-2px);
    box-shadow: 0 16px 40px rgba(0, 179, 164, 0.6);
}