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

body {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background-color: #0b1120;
    background-image: radial-gradient(ellipse at 20% 50%, rgba(30, 58, 138, 0.15) 0%, transparent 60%),
                      radial-gradient(ellipse at 80% 50%, rgba(88, 28, 135, 0.12) 0%, transparent 60%);
    color: #e2e8f0;
    font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    margin: 0;
    line-height: 1.6;
    overflow-x: hidden;
}

/* ---- background grid ---- */
.bg-grid {
    position: fixed;
    inset: 0;
    z-index: 0;
    background-image: linear-gradient(rgba(148, 163, 184, 0.03) 1px, transparent 1px),
                      linear-gradient(90deg, rgba(148, 163, 184, 0.03) 1px, transparent 1px);
    background-size: 60px 60px;
    pointer-events: none;
}

/* ---- animated orbs ---- */
.gradient-orb {
    position: fixed;
    border-radius: 50%;
    filter: blur(100px);
    pointer-events: none;
    z-index: 0;
}
.orb-1 {
    width: 500px;
    height: 500px;
    background: rgba(59, 130, 246, 0.15);
    top: -150px;
    right: -100px;
    animation: orbFloat 18s ease-in-out infinite;
}
.orb-2 {
    width: 400px;
    height: 400px;
    background: rgba(168, 85, 247, 0.12);
    bottom: -120px;
    left: -80px;
    animation: orbFloat 22s ease-in-out infinite reverse;
}
@keyframes orbFloat {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(40px, -50px) scale(1.1); }
    66% { transform: translate(-30px, 30px) scale(0.95); }
}

/* ---- header ---- */
header {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 80px 20px 40px;
}

h1 {
    font-size: clamp(2.5rem, 6vw, 4rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    margin: 0;
}

.glow-text {
    background: linear-gradient(135deg, #60a5fa, #a78bfa, #f472b6);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: glowPulse 4s ease-in-out infinite;
}
@keyframes glowPulse {
    0%, 100% { filter: brightness(1); }
    50% { filter: brightness(1.3); }
}

.subtitle {
    color: #94a3b8;
    font-size: 1.15rem;
    margin-top: 12px;
    font-weight: 400;
    letter-spacing: 0.02em;
}

/* ---- main ---- */
main {
    position: relative;
    z-index: 1;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px 60px;
    flex: 1;
}

h2 {
    font-size: 1.5rem;
    font-weight: 700;
    color: #cbd5e1;
    margin: 0 0 24px;
    display: flex;
    align-items: center;
    gap: 10px;
}
h2::after {
    content: "";
    flex: 1;
    height: 1px;
    background: linear-gradient(90deg, rgba(148, 163, 184, 0.3), transparent);
}

/* ---- project grid ---- */
.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
}

.project-card {
    display: flex;
    align-items: flex-start;
    gap: 18px;
    padding: 24px;
    background: rgba(30, 41, 59, 0.5);
    border: 1px solid rgba(148, 163, 184, 0.1);
    border-radius: 16px;
    text-decoration: none;
    color: inherit;
    backdrop-filter: blur(12px);
    transition: transform 0.25s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}
.project-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
    border-color: rgba(96, 165, 250, 0.3);
}

.card-icon {
    font-size: 2.5rem;
    flex-shrink: 0;
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(96, 165, 250, 0.1);
    border-radius: 14px;
}

.card-content h3 {
    font-size: 1.2rem;
    font-weight: 700;
    margin: 0 0 6px;
    color: #f1f5f9;
}

.card-content p {
    font-size: 0.9rem;
    color: #94a3b8;
    margin: 0 0 12px;
    line-height: 1.5;
}

.card-tag {
    display: inline-block;
    padding: 3px 10px;
    font-size: 0.75rem;
    font-weight: 600;
    color: #818cf8;
    background: rgba(129, 140, 248, 0.12);
    border: 1px solid rgba(129, 140, 248, 0.2);
    border-radius: 20px;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

/* ---- footer ---- */
footer {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 32px 20px;
    color: #475569;
    font-size: 0.85rem;
    border-top: 1px solid rgba(148, 163, 184, 0.08);
}

/* ---- responsive ---- */
@media (max-width: 640px) {
    header { padding: 50px 16px 30px; }
    .project-grid { grid-template-columns: 1fr; }
    .project-card { padding: 18px; }
}