/* Shared StudentCalcTools site styles */

/* Accessibility */
html {
    scroll-padding-top: 92px;
}

:focus-visible {
    outline: 3px solid var(--accent);
    outline-offset: 3px;
}

.skip-link {
    position: fixed;
    left: 12px;
    top: -80px;
    z-index: 10000;
    padding: 10px 18px;
    border-radius: 0 0 10px 10px;
    background: var(--blue);
    color: #fff;
    font-weight: 700;
    text-decoration: none;
    transition: top 0.2s ease;
}

.skip-link:focus {
    top: 0;
    left: 12px;
}


/* Scroll Progress */
.scroll-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0;
    height: 3px;
    z-index: 9999;
    background: var(--gradient-brand);
    box-shadow: 0 0 10px rgba(37, 99, 235, 0.5);
    transition: width 0.1s ease-out;
}


/* Header */
.site-nav {
    position: sticky;
    top: 0;
    z-index: 1000;
    min-height: 72px;
    padding: 12px 40px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    background: rgba(255, 255, 255, 0.88);
    border-bottom: 1px solid var(--border);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
}

[data-theme="dark"] .site-nav {
    background: rgba(2, 6, 23, 0.88);
}

.nav-logo {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--blue);
    font-size: 22px;
    font-weight: 800;
    letter-spacing: -0.5px;
    text-decoration: none;
    white-space: nowrap;
}

.nav-logo-icon {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    background: var(--gradient-brand);
    color: #fff;
    font-size: 14px;
    font-weight: 800;
}

.brand-name {
    color: var(--blue);
}

.brand-accent {
    color: var(--accent);
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 12px;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 16px;
}

.nav-links a {
    color: var(--muted);
    font-size: 14px;
    font-weight: 700;
    text-decoration: none;
    transition: color 0.2s ease;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
    color: var(--blue);
}

.nav-tag {
    padding: 5px 14px;
    border-radius: 20px;
    background: var(--blue-light);
    color: var(--blue);
    font-size: 12px;
    font-weight: 600;
    cursor: default;
    user-select: none;
}


/* Theme and Mobile Menu Buttons */
.theme-toggle,
.menu-toggle {
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border-strong);
    background: var(--blue-light);
    color: var(--blue);
    cursor: pointer;
    font-family: inherit;
    font-size: 13px;
    font-weight: 800;
}

.theme-toggle {
    width: 44px;
    min-width: 44px;
    height: 44px;
    padding: 0;
    border-radius: 50%;
    transition: transform 0.3s ease;
}

.theme-toggle:hover {
    transform: rotate(15deg) scale(1.1);
}

.theme-icon,
.theme-icon svg {
    width: 20px;
    height: 20px;
}

.theme-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.theme-icon svg {
    fill: none;
    stroke: currentColor;
    stroke-width: 1.9;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.theme-icon-sun {
    display: none;
    color: #fbbf24;
}

[data-theme="dark"] .theme-icon-sun {
    display: inline-flex;
}

[data-theme="dark"] .theme-icon-moon {
    display: none;
}

.menu-toggle {
    display: none;
    padding: 0 14px;
    border-radius: 999px;
}


/* Footer */
footer {
    padding: 50px 20px 26px;
    background: #0f172a;
    color: rgba(255, 255, 255, 0.5);
    text-align: center;
    font-size: 13px;
    font-weight: 500;
}

[data-theme="dark"] footer {
    background: #020617;
}

.footer-logo {
    margin-bottom: 8px;
    color: #fff;
    font-size: 22px;
    font-weight: 800;
}

.footer-logo span {
    color: var(--accent);
}

.footer-tagline {
    margin-bottom: 30px;
    font-size: 14px;
}

.footer-grid {
    max-width: 900px;
    margin: 0 auto 36px;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 20px;
    text-align: left;
}

.footer-col p.col-title {
    margin-bottom: 12px;
    color: #fff;
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.footer-col a {
    display: block;
    margin-bottom: 8px;
    color: rgba(255, 255, 255, 0.5);
    font-size: 13px;
    text-decoration: none;
    transition: color 0.2s ease;
}

.footer-col a:hover,
.footer-col a[aria-current="page"] {
    color: #fff;
}

.footer-bottom {
    padding-top: 22px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom span {
    color: var(--accent);
}


/* Tablet and Mobile Navigation */
@media (max-width: 860px) {
    .site-nav {
        padding: 10px 16px;
    }

    .nav-links {
        position: absolute;
        top: calc(100% + 8px);
        left: 14px;
        right: 14px;
        display: none;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: 10px;
        border: 1px solid var(--border-strong);
        border-radius: 16px;
        background: var(--card-bg);
        box-shadow: var(--shadow-md);
    }

    .nav-links.open {
        display: flex;
    }

    .nav-links a {
        display: block;
        padding: 13px 14px;
        border-radius: 10px;
        color: var(--text);
    }

    .nav-links a:hover,
    .nav-links a[aria-current="page"] {
        background: var(--blue-light);
        color: var(--blue);
    }

    .nav-tag {
        display: none;
    }

    .menu-toggle {
        display: inline-flex;
    }

    .footer-grid {
        grid-template-columns: 1fr 1fr;
        text-align: center;
    }
}


/* Small Mobile */
@media (max-width: 480px) {
    .site-nav {
        min-height: 64px;
        padding: 10px 12px;
    }

    .nav-logo {
        font-size: 18px;
    }

    .footer-grid {
        grid-template-columns: 1fr;
    }
}


/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
    .theme-toggle,
    .skip-link,
    .scroll-progress,
    .nav-links a,
    .footer-col a {
        transition: none;
    }
}