/* Critical landing styles only. Full app styles load asynchronously on /. */
:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #f0f4ff;
    --gray-50: #f9f8f6;
    --gray-100: #f6f5f4;
    --gray-400: #6f6b67;
    --gray-500: #6c6764;
    --gray-600: #615d59;
    --gray-700: #403d39;
    --gray-800: #31302e;
    --gray-900: #1b1a18;
    --bg-primary: #fff;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --transition-fast: 0.15s ease;
}
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
body {
    min-height: 100vh;
    min-height: 100dvh;
    overflow: hidden;
    padding-top: env(safe-area-inset-top);
    padding-right: env(safe-area-inset-right);
    padding-bottom: env(safe-area-inset-bottom);
    padding-left: env(safe-area-inset-left);
    background: var(--gray-100);
    color: var(--gray-800);
    font-family: var(--font-sans);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
.hidden {
    display: none !important;
}
.screen {
    display: none;
    height: 100vh;
    height: 100dvh;
    overflow-y: auto;
}
.screen.active {
    display: flex;
    flex-direction: column;
}
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 40px;
    padding: 10px 20px;
    border: 0;
    border-radius: 6px;
    font-family: var(--font-sans);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    text-decoration: none;
}
.btn-primary {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.08);
}
.btn-secondary {
    border: 1px solid rgba(0, 0, 0, 0.1);
    background: #fff;
    color: var(--gray-700);
}
.site-nav {
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
    background: #fff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}
.site-nav-inner {
    display: flex;
    align-items: center;
    max-width: 1200px;
    height: 56px;
    margin: 0 auto;
    padding: 0 24px;
}
.site-nav-brand {
    display: flex;
    align-items: center;
    flex-shrink: 0;
    gap: 10px;
    margin-right: 32px;
    color: inherit;
    text-decoration: none;
}
.site-nav-logo {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border-radius: 8px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #fff;
    font-size: 14px;
    font-weight: 700;
}
.site-nav-title {
    color: var(--gray-900);
    font-size: 16px;
    font-weight: 700;
}
.site-nav-toggle,
.site-nav-mobile-dark {
    display: none;
}
.site-nav-links {
    display: flex;
    align-items: center;
    gap: 4px;
    margin-left: auto;
}
.site-nav-link {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 8px 14px;
    border: 0;
    border-radius: 6px;
    background: transparent;
    color: var(--gray-700);
    font: 500 14px var(--font-sans);
    text-decoration: none;
    white-space: nowrap;
    cursor: pointer;
}
.site-nav-link.site-nav-app-link {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #fff;
    font-weight: 600;
    box-shadow: 0 10px 24px rgba(37, 99, 235, 0.18);
}
.site-nav-dropdown {
    position: relative;
}
.site-nav-menu,
.site-nav-menu-sm,
.site-nav-menu-mega {
    display: none;
    position: fixed;
    top: calc(56px + env(safe-area-inset-top));
    left: 50%;
    right: auto;
    z-index: 1001;
    grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
    gap: 8px;
    width: min(640px, calc(100vw - 24px));
    min-width: 0;
    max-height: calc(100dvh - 72px - env(safe-area-inset-top));
    overflow-y: auto;
    padding: 16px;
    border: 1px solid rgba(0, 0, 0, 0.08);
    border-radius: 12px;
    background: #fff;
    box-shadow: 0 12px 36px rgba(0, 0, 0, 0.12), 0 4px 12px rgba(0, 0, 0, 0.06);
    transform: translateX(-50%);
}
.site-nav-menu-sm {
    grid-template-columns: 1fr;
    width: min(220px, calc(100vw - 24px));
}
.site-nav-menu-mega {
    right: auto;
    left: 50%;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    width: min(940px, calc(100vw - 24px));
    min-width: 0;
    transform: translateX(-50%);
}
.site-nav-dropdown:hover .site-nav-menu,
.site-nav-dropdown:hover .site-nav-menu-sm,
.site-nav-dropdown:hover .site-nav-menu-mega {
    display: grid;
}
.nav-menu-group,
.nav-menu-col {
    padding: 8px;
}
.nav-menu-label,
.nav-menu-sublabel {
    display: block;
    color: var(--gray-900);
    font-size: 13px;
    font-weight: 700;
    white-space: nowrap;
}
.nav-menu-sublabel {
    padding: 0 4px 4px;
    color: var(--gray-400);
    font-size: 10px;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}
.site-nav-menu a,
.nav-menu-col a {
    display: block;
    padding: 4px;
    border-radius: 4px;
    color: var(--gray-600);
    font-size: 13px;
    text-decoration: none;
    white-space: nowrap;
}
@media (min-width: 981px) and (max-width: 1160px) {
    .site-nav-menu-mega {
        width: min(720px, calc(100vw - 24px));
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}
.landing-main {
    display: block;
}
.landing-container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 16px 24px 40px;
}
.landing-hero {
    display: grid;
    grid-template-columns: minmax(300px, 0.64fr) minmax(560px, 1.36fr);
    align-items: start;
    gap: 22px;
    max-width: 1040px;
    margin: 8px auto 12px;
    padding: 24px;
    border: 1px solid #e5e7eb;
    border-radius: 8px;
    background: linear-gradient(135deg, rgba(239, 246, 255, 0.92), rgba(255, 255, 255, 0.96) 52%, rgba(240, 253, 244, 0.9)), #fff;
    box-shadow: 0 10px 30px rgba(15, 23, 42, 0.06);
}
.landing-hero-copy {
    align-self: center;
    max-width: 520px;
    min-width: 0;
}
.landing-eyebrow {
    margin: 0 0 10px;
    color: var(--primary);
    font-size: 12px;
    font-weight: 800;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}
.landing-hero h1 {
    margin: 0;
    color: var(--gray-900);
    font-size: 38px;
    font-weight: 800;
    letter-spacing: 0;
    line-height: 1.06;
}
.landing-hero h2 {
    margin: 8px 0 0;
    color: var(--primary);
    font-size: 22px;
    font-weight: 700;
    letter-spacing: 0;
}
.landing-hero .landing-subtitle {
    max-width: 560px;
    margin: 12px 0 0;
    color: var(--gray-600);
    font-size: 15px;
    line-height: 1.5;
}
.landing-disc-select-wrap {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(170px, 220px);
    gap: 12px 14px;
    align-items: start;
    padding: 16px;
    border: 1px solid rgba(37, 99, 235, 0.12);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.9);
}
.discipline-selector-heading {
    grid-column: 1 / -1;
    color: var(--gray-900);
    font-size: 14px;
    font-weight: 800;
}
.discipline-selector {
    display: none;
    flex-wrap: wrap;
    align-items: center;
    justify-content: flex-start;
    gap: 7px;
    margin-top: 0;
}
.discipline-selector.visible {
    display: flex;
}
.disc-group-label {
    width: 100%;
    margin: 0 0 -1px;
    color: var(--primary);
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-align: left;
    text-transform: uppercase;
}
.disc-group-pe {
    margin-top: 5px;
    color: #7c3aed;
}
.discipline-btn {
    padding: 6px 11px;
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: 999px;
    background: transparent;
    color: var(--gray-600);
    font: 600 12px/1.15 var(--font-sans);
    white-space: nowrap;
    cursor: pointer;
}
.discipline-btn.active {
    border-color: var(--primary);
    background: var(--primary);
    color: #fff;
    box-shadow: 0 2px 8px rgba(37, 99, 235, 0.25);
}
.discipline-btn[data-discipline="civil"].active { background: #f59e0b; border-color: #f59e0b; }
.discipline-btn[data-discipline="mechanical"].active { background: #b91c1c; border-color: #b91c1c; }
.discipline-btn[data-discipline="chemical"].active { background: #166534; border-color: #166534; }
.discipline-btn[data-discipline="environmental"].active { background: #0e7490; border-color: #0e7490; }
.discipline-btn[data-discipline="other-disciplines"].active { background: #374151; border-color: #374151; }
.discipline-btn-pe.active { background: #7c3aed; border-color: #7c3aed; }
.discipline-btn[data-discipline="pe-elec-ecc"].active { background: #0f766e; border-color: #0f766e; }
.landing-disc-cta {
    display: flex;
    flex-direction: column;
    gap: 10px;
    max-width: 220px;
    min-width: 0;
}
.landing-hero-actions {
    display: flex;
    flex-direction: column;
    flex-wrap: wrap;
    gap: 8px;
    align-items: stretch;
    margin-top: 0;
}
.landing-disc-cta .landing-hero-actions .btn {
    width: 100%;
}
.landing-disc-cta .btn-buy {
    min-height: 52px;
    white-space: normal;
    line-height: 1.2;
}
.landing-text-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 42px;
    padding: 0 4px;
    color: var(--primary);
    font-size: 14px;
    font-weight: 700;
    text-decoration: none;
}
.landing-proof-strip {
    display: grid;
    grid-column: 1 / -1;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 8px;
    margin-top: 0;
}
.landing-proof-strip span {
    display: inline-flex;
    justify-content: center;
    padding: 7px 10px;
    border: 1px solid rgba(37, 99, 235, 0.16);
    border-radius: 6px;
    background: rgba(255, 255, 255, 0.75);
    color: #374151;
    font-size: 12px;
    font-weight: 700;
    text-align: center;
}
@media (max-width: 980px) {
    .landing-hero {
        grid-template-columns: 1fr;
    }
}
@media (max-width: 860px) {
    .landing-disc-select-wrap {
        grid-template-columns: 1fr;
    }
    .landing-disc-cta {
        max-width: 100%;
    }
    .landing-hero-actions {
        flex-direction: row;
    }
    .landing-disc-cta .landing-hero-actions .btn {
        flex: 1 1 auto;
        width: auto;
    }
}
@media (max-width: 980px) {
    .site-nav-toggle,
    .site-nav-mobile-dark {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        width: 36px;
        height: 36px;
        margin-left: auto;
        border: 0;
        border-radius: 50%;
        background: transparent;
        color: var(--gray-600);
        font-size: 22px;
        cursor: pointer;
    }
    .site-nav-mobile-dark {
        margin-right: 4px;
        font-size: 18px;
    }
    .site-nav-mobile-dark::before {
        content: "\1F319";
    }
    .site-nav-toggle {
        margin-left: 0;
    }
    .site-nav-links {
        display: none;
        position: absolute;
        top: 56px;
        right: 0;
        left: 0;
        flex-direction: column;
        align-items: stretch;
        max-height: calc(100dvh - 56px);
        overflow-y: auto;
        padding: 12px 16px;
        border-bottom: 1px solid rgba(0, 0, 0, 0.08);
        background: #fff;
        box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
    }
    .nav-open .site-nav-links {
        display: flex;
    }
    .site-nav-link {
        justify-content: space-between;
        padding: 12px 8px;
    }
    .site-nav-dropdown {
        position: static;
    }
    .site-nav-menu,
    .site-nav-menu-sm,
    .site-nav-menu-mega {
        position: static;
        grid-template-columns: 1fr;
        width: auto;
        min-width: auto;
        max-height: none;
        overflow: visible;
        padding: 4px 0 4px 16px;
        border: 0;
        box-shadow: none;
        transform: none;
    }
    .site-nav-menu:not(.site-nav-menu-mega):not(.site-nav-menu-sm),
    .site-nav-menu-sm,
    .site-nav-menu-mega {
        grid-template-columns: 1fr;
    }
    .site-nav-dropdown:hover .site-nav-menu,
    .site-nav-dropdown:hover .site-nav-menu-sm,
    .site-nav-dropdown:hover .site-nav-menu-mega {
        display: none;
    }
    .site-nav-dropdown.menu-open .site-nav-menu,
    .site-nav-dropdown.menu-open .site-nav-menu-sm,
    .site-nav-dropdown.menu-open .site-nav-menu-mega {
        display: grid;
    }
    .site-nav-menu a,
    .nav-menu-col a,
    .nav-menu-label,
    .nav-menu-sublabel {
        white-space: normal;
    }
}
@media (max-width: 640px) {
    .landing-container {
        padding: 12px 14px 32px;
    }
    .landing-hero {
        gap: 18px;
        padding: 20px 16px;
    }
    .landing-hero h1 {
        font-size: 32px;
    }
    .landing-hero h2 {
        font-size: 18px;
    }
    .landing-hero .landing-subtitle {
        font-size: 14px;
    }
    .landing-proof-strip {
        grid-template-columns: 1fr;
    }
    .landing-hero-actions .btn,
    .landing-hero-actions .landing-text-link {
        width: 100%;
        justify-content: center;
    }
}
body.dark-mode {
    background: #151412;
    color: #e8e6e1;
}
body.dark-mode .site-nav,
body.dark-mode .site-nav-links {
    border-bottom-color: #33302d;
    background: #0f1120;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}
body.dark-mode .site-nav-title,
body.dark-mode .landing-hero h1,
body.dark-mode .discipline-selector-heading {
    color: #e8e6e1;
}
body.dark-mode .site-nav-link {
    color: #b0ada8;
}
body.dark-mode .site-nav-link.site-nav-app-link {
    color: #fff;
}
body.dark-mode .site-nav-menu,
body.dark-mode .site-nav-menu-sm,
body.dark-mode .site-nav-menu-mega,
body.dark-mode .landing-disc-select-wrap {
    border-color: #33302d;
    background: #1e1d1b;
}
body.dark-mode .landing-hero {
    border-color: #3a3733;
    background: linear-gradient(135deg, rgba(30, 35, 72, 0.92), rgba(31, 30, 28, 0.96) 52%, rgba(20, 83, 45, 0.35));
}
body.dark-mode .landing-hero .landing-subtitle {
    color: #b8b5b0;
}
body.dark-mode .landing-proof-strip span {
    border-color: rgba(147, 197, 253, 0.24);
    background: rgba(37, 99, 235, 0.16);
    color: #bfdbfe;
}
body.dark-mode .site-nav-mobile-dark::before {
    content: "\2600";
}