* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
body {
    min-height: 100vh;
    font-family: Arial, sans-serif;
    background: #1a1a2e;
    color: #e0e0e0;
}
header {
    background: #16213e;
    padding: 1.2rem 2rem;
    border-bottom: 2px solid #00d4aa;
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.site-title {
    font-size: 1.4rem;
    color: #00d4aa;
    font-weight: bold;
    text-decoration: none;
}
nav a {
    color: #e0e0e0;
    text-decoration: none;
    margin-left: 1.2rem;
    padding: 0.4rem 1rem;
    border-radius: 4px;
    transition: background 0.2s;
    display: inline-block;
}
nav a:hover {
    background: rgba(0, 212, 170, 0.2);
}
main {
    max-width: 960px;
    margin: 0 auto;
    padding: 3rem 2rem;
}
.hero {
    text-align: center;
    margin-bottom: 2.5rem;
}
.hero h1 {
    font-size: 3rem;
    color: #00d4aa;
    margin-bottom: 0.8rem;
}
.hero p {
    font-size: 1.2rem;
    opacity: 0.8;
}
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1.5rem;
}
.card {
    background: #16213e;
    border: 1px solid rgba(0, 212, 170, 0.25);
    border-radius: 8px;
    padding: 1.5rem;
}
.card h2 {
    color: #00d4aa;
    font-size: 1.15rem;
    margin-bottom: 0.8rem;
}
.card ul {
    list-style: none;
    padding: 0;
}
.card ul li {
    font-size: 0.95rem;
    line-height: 1.6;
    opacity: 0.8;
    padding: 0.4rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}
.card ul li:last-child {
    border-bottom: none;
}
.loops {
    margin-top: 3rem;
}
.loops h2 {
    font-size: 1.8rem;
    color: #00d4aa;
    margin-bottom: 0.5rem;
}
.loops-intro {
    opacity: 0.8;
    margin-bottom: 2rem;
    font-size: 1rem;
}
.loop-diagram {
    background: #16213e;
    border: 1px solid rgba(0, 212, 170, 0.25);
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}
.loop-diagram h3 {
    color: #00d4aa;
    font-size: 1.1rem;
    margin-bottom: 0.4rem;
}
.loop-desc {
    font-size: 0.9rem;
    opacity: 0.7;
    margin-bottom: 1.2rem;
}
.loop-flow {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
}
.loop-step {
    background: #0f3460;
    border: 1px solid rgba(0, 212, 170, 0.4);
    border-radius: 6px;
    padding: 0.5rem 0.8rem;
    font-size: 0.9rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    min-width: 90px;
    text-align: center;
}
.loop-step--trigger {
    border-color: rgba(0, 212, 170, 0.8);
}
.loop-step--feedback {
    border-color: rgba(0, 212, 170, 0.8);
    background: #16213e;
}
.step-sub {
    font-size: 0.72rem;
    opacity: 0.65;
    margin-top: 0.2rem;
    white-space: nowrap;
}
.loop-arrow {
    color: #00d4aa;
    font-size: 1.2rem;
    opacity: 0.7;
    flex-shrink: 0;
}
.loop-back {
    font-size: 0.82rem;
    color: #00d4aa;
    opacity: 0.6;
    font-style: italic;
    padding-left: 0.2rem;
}