/* Base styles for AI & Systems Co-Design Team website */

/* Meta color palette */
:root {
    --meta-light-blue: #0082fb;
    --meta-blue: #0064e0;
    --meta-black: #000000;
    --meta-gray: #1c1e21;
    --meta-darkslategray: #1c2b33;
    --meta-darkslategray-light: #344854;
}

/* Typography and base styles */
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.6;
    max-width: 900px;
    margin: 0 auto;
    padding: 40px 20px 20px 20px;
    color: var(--meta-gray);
}

/* Links */
a {
    text-decoration: none;
    color: var(--meta-blue);
}

a:hover {
    text-decoration: underline;
    color: var(--meta-light-blue);
}

/* Headings */
h1 {
    color: var(--meta-gray);
    font-size: 1.8em;
    margin-top: 2em;
    margin-bottom: 0.5em;
    padding-bottom: 0.3em;
    border-bottom: 2px solid var(--meta-light-blue);
}

h2 {
    color: var(--meta-gray);
    font-size: 1.5em;
    margin-top: 2em;
    margin-bottom: 0.5em;
    padding-bottom: 0.3em;
    border-bottom: 1px solid #ddd;
}

h3 {
    color: var(--meta-darkslategray-light);
    font-size: 1.2em;
    margin-top: 1.5em;
    margin-bottom: 0.5em;
}

h4 {
    color: var(--meta-darkslategray-light);
    font-size: 1.1em;
    margin-top: 1.5em;
    margin-bottom: 0.5em;
}

/* Lists */
ul, ol {
    margin-bottom: 0;
}

/* Lists following headings - tighter spacing */
h2 + ul,
h3 + ul,
h2 + p + ul,
h3 + p + ul {
    margin-top: -0.5em;
}

/* Images */
img {
    max-width: 100%;
    height: auto;
}

/* Paragraphs */
p {
    margin-bottom: 1em;
}

/* Logo header */
.logo-header {
    display: inline-flex;
    align-items: center;
    gap: 12px;
}

.logo-header img {
    display: block;
    height: 2em;
}

.logo-header span {
    font-family: "Facebook Sans", sans-serif;
    font-size: 2em;
    color: var(--meta-gray);
    line-height: 45px;
}

/* Announcement banner */
.banner {
    background: var(--meta-darkslategray-light);
    color: #fff;
    padding: 20px 25px 20px 90px;
    border-radius: 12px;
    margin: 20px 0;
    border-left: 8px solid var(--meta-light-blue);
    font-size: 1.2em;
    position: relative;
}

.banner::before {
    content: "";
    position: absolute;
    left: 20px;
    top: 20px;
    width: 55px;
    height: 55px;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='white'%3E%3Cpath d='M18 11v2h4v-2h-4zm-2 6.61c.96.71 2.21 1.65 3.2 2.39.4-.53.8-1.07 1.2-1.6-.99-.74-2.24-1.68-3.2-2.4-.4.54-.8 1.08-1.2 1.61zM20.4 5.6c-.4-.53-.8-1.07-1.2-1.6-.99.74-2.24 1.68-3.2 2.4.4.53.8 1.07 1.2 1.6.96-.72 2.21-1.65 3.2-2.4zM4 9c-1.1 0-2 .9-2 2v2c0 1.1.9 2 2 2h1v4h2v-4h1l5 3V6L8 9H4zm11.5 3c0-1.33-.58-2.53-1.5-3.35v6.69c.92-.81 1.5-2.01 1.5-3.34z'/%3E%3C/svg%3E");
    background-size: contain;
    background-repeat: no-repeat;
}

/* Award badges */
.award, .top-picks {
    display: inline-block;
    color: #fff;
    padding: 2px 8px 2px 6px;
    border-radius: 4px;
    font-size: 0.85em;
    font-weight: bold;
    margin-left: 4px;
}

.award {
    background: var(--meta-light-blue);
}

.top-picks {
    background: var(--meta-darkslategray-light);
}

.award::before, .top-picks::before {
    content: "";
    display: inline-block;
    width: 14px;
    height: 14px;
    margin-right: 4px;
    vertical-align: middle;
    background-image: url("images/stars-4.svg");
    background-size: contain;
    background-repeat: no-repeat;
}

/* Section spacing */
section, .section {
    margin-bottom: 3em;
}

/* ===================
   Responsive Design
   =================== */

/* Tablet (768px and below) */
@media screen and (max-width: 768px) {
    body {
        padding: 15px;
    }

    h1 {
        font-size: 1.5em;
    }

    h2 {
        font-size: 1.3em;
    }

    .banner {
        padding: 15px 20px 15px 70px;
        font-size: 1.2em;
    }

    .banner::before {
        width: 40px;
        height: 40px;
        left: 15px;
    }
}

/* Mobile (480px and below) */
@media screen and (max-width: 480px) {
    body {
        padding: 12px;
        font-size: 14px;
    }

    h1 {
        font-size: 1.3em;
        margin-top: 1.5em;
    }

    h2 {
        font-size: 1.2em;
        margin-top: 1.5em;
    }

    h3 {
        font-size: 1.1em;
    }

    .banner {
        padding: 50px 15px 15px 15px;
        font-size: 1em;
        text-align: left;
    }

    .banner::before {
        width: 30px;
        height: 30px;
        left: 50%;
        top: 15px;
        transform: translateX(-50%);
    }

    /* Stack badges on new line on mobile */
    .award, .top-picks {
        display: inline-block;
        margin-top: 4px;
        margin-left: 0;
    }

    ul {
        padding-left: 20px;
    }

    li {
        margin-bottom: 0.5em;
    }
}