:root {
    --bg-start: #081022;
    --bg-end: #0f1b36;
    --panel: rgba(16, 28, 53, 0.9);
    --panel-border: rgba(255, 255, 255, 0.16);
    --text-main: #e8f0ff;
    --text-muted: #c2d3f8;
    --accent: #39d98a;
    --accent-2: #25b7ff;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: clamp(14px, 3vw, 28px);
    color: var(--text-main);
    font-family: "Manrope", "Segoe UI", sans-serif;
    background:
        radial-gradient(circle at 10% 15%, rgba(37, 183, 255, 0.18), transparent 36%),
        radial-gradient(circle at 85% 2%, rgba(57, 217, 138, 0.16), transparent 30%),
        linear-gradient(145deg, var(--bg-start), var(--bg-end));
    min-height: 100vh;
}

.project-essay {
    max-width: 980px;
    margin: 0 auto;
    padding: clamp(18px, 4vw, 34px);
    border-radius: 22px;
    border: 1px solid var(--panel-border);
    background: var(--panel);
    box-shadow: 0 18px 40px rgba(3, 10, 24, 0.42);
    line-height: 1.8;
}

.project-essay h2,
.project-essay h3 {
    font-family: "Syne", "Segoe UI", sans-serif;
    color: #f5f9ff;
}

.project-essay h2 {
    font-size: clamp(1.4rem, 2.8vw, 2.1rem);
    line-height: 1.3;
}

.project-essay h3 {
    margin-top: 26px;
    margin-bottom: 8px;
    position: relative;
    padding-left: 14px;
}

.project-essay h3::before {
    content: "";
    position: absolute;
    left: 0;
    top: 0.4em;
    width: 6px;
    height: 1em;
    border-radius: 99px;
    background: linear-gradient(180deg, var(--accent-2), var(--accent));
}

.project-essay p,
.project-essay li {
    color: var(--text-muted);
}

.project-essay ul {
    margin: 0;
    padding-left: 18px;
}

.project-essay iframe,
.youtubevideo {
    width: 100%;
    max-width: 860px;
    aspect-ratio: 16 / 9;
    height: auto;
    border: 1px solid var(--panel-border);
    border-radius: 14px;
    box-shadow: 0 12px 30px rgba(2, 9, 22, 0.34);
}

.pdfviewer {
    width: 100%;
    min-height: 70vh;
    border: 1px solid var(--panel-border);
    border-radius: 14px;
    background: #ffffff;
}

.project-essay span[style] {
    border: 1px solid rgba(255, 255, 255, 0.18);
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.08);
}

@media (max-width: 700px) {
    body {
        padding: 12px;
    }

    .project-essay {
        border-radius: 16px;
        padding: 16px;
    }

    .pdfviewer {
        min-height: 62vh;
    }
}