/* Shared styles for the Sideris site (index.html + privacy.html).
   Palette and typography mirror the Sideris app: dark navy surfaces, cyan
   accent, light-gray text, Inter for body and JetBrains Mono for scientific
   labels. The two web fonts are self-hosted (OFL) from assets/fonts/ (no
   third-party font CDN), with system UI/monospace fallbacks. */

@font-face { font-family: "Inter"; font-style: normal; font-weight: 400; font-display: swap; src: url("fonts/inter-400.woff2") format("woff2"); }
@font-face { font-family: "Inter"; font-style: normal; font-weight: 500; font-display: swap; src: url("fonts/inter-500.woff2") format("woff2"); }
@font-face { font-family: "Inter"; font-style: normal; font-weight: 600; font-display: swap; src: url("fonts/inter-600.woff2") format("woff2"); }
@font-face { font-family: "Inter"; font-style: normal; font-weight: 700; font-display: swap; src: url("fonts/inter-700.woff2") format("woff2"); }
@font-face { font-family: "Inter"; font-style: normal; font-weight: 800; font-display: swap; src: url("fonts/inter-800.woff2") format("woff2"); }
@font-face { font-family: "JetBrains Mono"; font-style: normal; font-weight: 400; font-display: swap; src: url("fonts/jetbrains-mono-400.woff2") format("woff2"); }
@font-face { font-family: "JetBrains Mono"; font-style: normal; font-weight: 500; font-display: swap; src: url("fonts/jetbrains-mono-500.woff2") format("woff2"); }

:root {
    --bg: #1A1A2E;            /* app background: dark navy */
    --surface: #232340;       /* panels */
    --card: #2A2A4A;          /* card tiles */
    --accent: #00E5FF;        /* cyan */
    --accent-dim: #0097A7;    /* teal */
    --ink: #E0E0E0;           /* primary text */
    --head: #F2F5F8;          /* headings */
    --muted: #AEB7C1;         /* secondary text (brightened for contrast, ~7.9:1) */
    --border: rgba(255, 255, 255, 0.09);
    --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
    font-family: var(--font-sans);
    line-height: 1.65;
    color: var(--ink);
    margin: 0;
    background-color: var(--bg);
    background-image: radial-gradient(1100px 620px at 50% -12%, #2A2A50 0%, rgba(42, 42, 80, 0) 62%);
    background-repeat: no-repeat;
    background-attachment: fixed;
    -webkit-font-smoothing: antialiased;
}

.wrap { max-width: 860px; margin: 0 auto; padding: 0 22px; }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
a:focus-visible, button:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
    border-radius: 4px;
}

h1, h2, h3 { color: var(--head); letter-spacing: -0.01em; }
h1 { font-size: 2.6em; margin: 0 0 12px; font-weight: 800; }
h2 { font-size: 1.6em; margin-top: 56px; font-weight: 700; }
h3 { margin-top: 28px; font-weight: 600; }
p { margin-bottom: 15px; text-align: justify; }
ul { margin-bottom: 20px; }
li { margin-bottom: 10px; text-align: justify; }
strong { color: var(--head); }

/* Monospace eyebrow / label (scientific accent) */
.eyebrow {
    font-family: var(--font-mono);
    text-transform: uppercase;
    letter-spacing: 0.22em;
    font-size: 0.72rem;
    color: var(--accent);
    margin: 0 0 10px;
}

/* Header */
.site-header {
    position: sticky;
    top: 0;
    z-index: 10;
    border-bottom: 1px solid var(--border);
    background: rgba(26, 26, 46, 0.72);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}
.site-header .wrap {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 22px;
}
.brand {
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--head);
    font-weight: 700;
    font-size: 1.2em;
}
.brand:hover { text-decoration: none; }
.brand img { width: 36px; height: 36px; flex-shrink: 0; }  /* corners already rounded in the PNG */
.site-nav a { margin-left: 20px; color: var(--muted); font-weight: 500; }
.site-nav a:hover { color: var(--accent); text-decoration: none; }

/* Hero (home) */
.hero { position: relative; padding-top: 76px; padding-bottom: 28px; text-align: center; }
.hero::before {   /* soft cyan glow behind the logo */
    content: "";
    position: absolute;
    left: 0; right: 0; top: -20px;
    height: 320px;
    background: radial-gradient(440px 240px at 50% 26%, rgba(0, 229, 255, 0.15), rgba(0, 229, 255, 0) 70%);
    pointer-events: none;
    z-index: -1;
}
.hero::after {    /* faint starfield */
    content: "";
    position: absolute;
    inset: 0;
    z-index: -1;
    pointer-events: none;
    background-image:
        radial-gradient(1.5px 1.5px at 12% 28%, rgba(255, 255, 255, 0.7), transparent),
        radial-gradient(1.5px 1.5px at 84% 20%, rgba(255, 255, 255, 0.55), transparent),
        radial-gradient(1px 1px at 68% 60%, rgba(255, 255, 255, 0.5), transparent),
        radial-gradient(1px 1px at 26% 72%, rgba(255, 255, 255, 0.5), transparent),
        radial-gradient(1.5px 1.5px at 50% 10%, rgba(0, 229, 255, 0.6), transparent),
        radial-gradient(1px 1px at 92% 66%, rgba(255, 255, 255, 0.45), transparent),
        radial-gradient(1px 1px at 8% 52%, rgba(255, 255, 255, 0.4), transparent);
}
.hero .logo-lg {
    width: 104px;
    height: 104px;
    margin-bottom: 18px;
    filter: drop-shadow(0 6px 26px rgba(0, 229, 255, 0.22));
}
.hero h1 { font-size: 3em; }
.tagline {
    font-size: 1.2em;
    color: var(--muted);
    max-width: 760px;
    margin: 0 auto 26px;
    text-align: center;
}
.cta { margin: 8px 0; text-align: center; }
.badge {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    letter-spacing: 0.02em;
    color: var(--accent);
    background: rgba(0, 229, 255, 0.08);
    border: 1px solid rgba(0, 229, 255, 0.35);
    border-radius: 999px;
    padding: 9px 18px;
}

/* Features (home) */
.features { padding-top: 40px; padding-bottom: 8px; }
.features h2 { padding-bottom: 12px; position: relative; }
.features h2::after {   /* short cyan accent rule */
    content: "";
    position: absolute;
    left: 0; bottom: 0;
    width: 48px; height: 3px;
    background: var(--accent);
    border-radius: 2px;
}
.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 18px;
    margin-top: 28px;
}
.feature {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 22px;
    transition: transform 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
}
.feature:hover {
    transform: translateY(-3px);
    border-color: rgba(0, 229, 255, 0.4);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.35);
}
.feature h3 {
    margin: 0 0 10px;
    font-family: var(--font-mono);
    font-weight: 500;
    font-size: 1.02em;
    letter-spacing: 0;
    color: var(--accent);
    text-align: center;
}
.feature p { margin: 0; text-align: justify; color: var(--muted); }

/* Document (privacy) */
.doc { padding: 32px 0 8px; }
.doc h1 { font-size: 2.1em; margin-top: 8px; }
.doc h2 { padding-bottom: 12px; border-bottom: 1px solid var(--border); }
.contact-info { font-weight: bold; color: var(--head); }

/* Footer */
.site-footer {
    border-top: 1px solid var(--border);
    margin-top: 72px;
    padding: 28px 0;
    color: var(--muted);
    font-size: 0.93em;
}
.site-footer .wrap {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 20px;
    justify-content: space-between;
    align-items: center;
}
.site-footer a { color: var(--muted); }
.site-footer a:hover { color: var(--accent); }

/* Small screens */
@media (max-width: 560px) {
    .hero { padding-top: 56px; }
    .hero h1 { font-size: 2.4em; }
    h1 { font-size: 2.1em; }
}

/* Theme toggle button */
.theme-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    padding: 0;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: transparent;
    color: var(--muted);
    cursor: pointer;
    transition: color 0.15s ease, border-color 0.15s ease;
}
.theme-toggle:hover { color: var(--accent); border-color: var(--accent); }
.theme-toggle svg { width: 20px; height: 20px; }
.theme-toggle .icon-moon { display: none; }   /* dark (default): show sun */
:root[data-theme="light"] .theme-toggle .icon-sun { display: none; }
:root[data-theme="light"] .theme-toggle .icon-moon { display: block; }

/* Light (high-contrast) theme. Dark stays the default in :root above. */
:root[data-theme="light"] {
    --bg: #FFFFFF;
    --surface: #F2F4F7;
    --card: #F5F7FA;
    --accent: #036B7B;        /* deep teal: readable on white (~5.8:1) */
    --accent-dim: #0097A7;
    --ink: #1A1A2E;           /* near-black navy text (~14:1) */
    --head: #0E1230;
    --muted: #455160;         /* ~7.5:1 on white */
    --border: rgba(0, 0, 0, 0.14);
}
:root[data-theme="light"] body { background-image: none; }
:root[data-theme="light"] .site-header { background: rgba(255, 255, 255, 0.82); }
:root[data-theme="light"] .hero::after { display: none; }   /* starfield is invisible on white */
:root[data-theme="light"] .badge {
    background: rgba(3, 107, 123, 0.08);
    border-color: rgba(3, 107, 123, 0.45);
}
:root[data-theme="light"] .feature:hover {
    border-color: rgba(3, 107, 123, 0.45);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.12);
}

/* Respect reduced-motion preferences */
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    .feature, .theme-toggle { transition: none; }
}