main > .container {
    padding: 70px 15px 20px;
    display: flex;
    flex-direction: column;
    min-height: 100%;
}

.not-set {
    color: var(--bs-danger);
    font-style: italic;
}

/* add sorting icons to gridview sort links */
a.asc:after, a.desc:after {
    content: '';
    left: 3px;
    display: inline-block;
    width: 0;
    height: 0;
    border: solid 5px transparent;
    margin: 4px 4px 2px 4px;
    background: transparent;
}

a.asc:after {
    border-bottom: solid 7px var(--bs-body-color);
    border-top-width: 0;
}

a.desc:after {
    border-top: solid 7px var(--bs-body-color);
    border-bottom-width: 0;
}

.grid-view th {
    white-space: nowrap;
}

.hint-block {
    display: block;
    margin-top: 5px;
    color: var(--bs-secondary-color);
}

.error-summary {
    color: var(--bs-danger-text-emphasis);
    background: var(--bs-danger-bg-subtle);
    border-left: 3px solid var(--bs-danger-border-subtle);
    padding: 10px 20px;
    margin: 0 0 15px 0;
}

/* align navbar brand baseline with nav links */
.navbar > .container,
.navbar > .container-fluid {
    align-items: baseline;
}

/* style navbar logout link color, hover state, and mobile layout */
.navbar-nav .nav-link.logout {
    color: var(--bs-navbar-color);
}

@media (max-width: 767.98px) {
    .navbar-nav .nav-link.logout {
        display: block;
        text-align: left;
        width: 100%;
        padding: 10px 0;
    }
}

.navbar-nav .nav-link.logout:focus,
.navbar-nav .nav-link.logout:hover {
    color: var(--bs-navbar-hover-color);
}



/* footer logo: light logo by default (light bg-body-tertiary), dark logo for dark theme */
.footer-logo-dark { display: none; }

[data-bs-theme="dark"] .footer-logo-light { display: none; }
[data-bs-theme="dark"] .footer-logo-dark  { display: inline-block; }

/* Yii brand button */
.btn-yii {
    background: linear-gradient(135deg, #40B3D8, #3a9cbd);
    border: none;
    font-weight: 600;
    letter-spacing: .02em;
    transition: opacity .2s, transform .1s;
}

.btn-yii:hover {
    opacity: .9;
    transform: translateY(-1px);
}

.btn-yii:active {
    transform: translateY(0);
}

/* form inputs: seamless icon inside input (Volt style) */
.form-card .input-group {
    border: var(--bs-border-width) solid var(--bs-border-color);
    border-radius: var(--bs-border-radius);
    overflow: hidden;
    transition: border-color .15s ease-in-out, box-shadow .15s ease-in-out;
}

.form-card .input-group .input-group-text {
    background: var(--bs-body-bg);
    border: 0;
    padding-left: 1rem;
    padding-right: .75rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.form-card .input-group .form-control {
    border: 0;
}

.form-card .input-group .form-control:focus {
    box-shadow: none;
}

.form-card .input-group:focus-within {
    border-color: var(--bs-primary);
    box-shadow: 0 0 0 .25rem rgba(var(--bs-primary-rgb), .25);
}

/* validation styles for browsers that support :has() */
@supports selector(.input-group:has(.is-invalid)) {
    .form-card .input-group:has(.is-invalid) ~ .invalid-feedback {
        display: block;
        margin-top: .35rem;
        margin-bottom: .5rem;
    }

    .form-card .input-group:has(.is-invalid) {
        border-color: var(--bs-danger);
    }

    .form-card .input-group:has(.is-invalid):focus-within {
        box-shadow: 0 0 0 .25rem rgba(var(--bs-danger-rgb), .25);
    }
}

/* fallback validation styles for browsers without :has() support */
@supports not selector(.input-group:has(.is-invalid)) {
    .form-card .invalid-feedback:not(:empty) {
        display: block;
        margin-top: .35rem;
        margin-bottom: .5rem;
    }

    .form-card .input-group .form-control.is-invalid {
        border: var(--bs-border-width) solid var(--bs-danger);
    }

    .form-card .input-group .form-control.is-invalid:focus {
        box-shadow: 0 0 0 .25rem rgba(var(--bs-danger-rgb), .25);
    }
}

/* login inputs: seamless icon inside input (Volt style) */
.login-split-card .input-group {
    border: var(--bs-border-width) solid var(--bs-border-color);
    border-radius: var(--bs-border-radius);
    overflow: hidden;
    transition: border-color .15s ease-in-out, box-shadow .15s ease-in-out;
}

.login-split-card .input-group .input-group-text {
    background: transparent;
    border: 0;
    padding-left: 1rem;
    padding-right: .75rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.login-split-card .input-group .form-control {
    border: 0;
    background: transparent;
}

.login-split-card .input-group .form-control:focus {
    box-shadow: none;
}

.login-split-card .input-group:focus-within {
    border-color: var(--bs-primary);
    box-shadow: 0 0 0 .25rem rgba(var(--bs-primary-rgb), .25);
}

/* validation styles for login split card (browsers with :has()) */
@supports selector(.input-group:has(.is-invalid)) {
    .login-split-card .input-group:has(.is-invalid) ~ .invalid-feedback {
        display: block;
        margin-top: .35rem;
        margin-bottom: .5rem;
    }

    .login-split-card .input-group:has(.is-invalid) {
        border-color: var(--bs-danger);
    }

    .login-split-card .input-group:has(.is-invalid):focus-within {
        box-shadow: 0 0 0 .25rem rgba(var(--bs-danger-rgb), .25);
    }
}

/* fallback validation styles for login split card (browsers without :has()) */
@supports not selector(.input-group:has(.is-invalid)) {
    .login-split-card .invalid-feedback:not(:empty) {
        display: block;
        margin-top: .35rem;
        margin-bottom: .5rem;
    }

    .login-split-card .input-group .form-control.is-invalid {
        border: var(--bs-border-width) solid var(--bs-danger);
    }

    .login-split-card .input-group .form-control.is-invalid:focus {
        box-shadow: 0 0 0 .25rem rgba(var(--bs-danger-rgb), .25);
    }
}

/* login split card */
.login-split-card {
    border-radius: 1rem;
    box-shadow: 0 4px 24px rgba(0, 0, 0, .10);
    background-color: var(--bs-gray-100);
    width: 100%;
    max-width: 900px;
}

.login-split-card-wide {
    max-width: 960px;
}

.login-brand-title {
    font-size: 1.75rem;
    line-height: 1.3;
}

.login-brand-text {
    font-size: .9rem;
}

.login-brand-panel {
    background: linear-gradient(135deg, #40B3D8 0%, #3a9cbd 40%, #83C933 100%);
    position: relative;
    min-height: 480px;
}

.login-brand-panel::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(circle at 20% 80%, rgba(241, 138, 42, .25) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(131, 201, 51, .2) 0%, transparent 40%);
    pointer-events: none;
}

.login-btn {
    background: linear-gradient(135deg, #40B3D8, #3a9cbd);
    border: none;
    font-weight: 600;
    letter-spacing: .02em;
    transition: opacity .2s, transform .1s;
}

.login-btn:hover {
    opacity: .9;
    transform: translateY(-1px);
}

.login-btn:active {
    transform: translateY(0);
}

/* dark mode login card */
[data-bs-theme="dark"] .login-split-card {
    background-color: var(--bs-body-bg);
    box-shadow: 0 0 0 1px var(--bs-border-color), 0 4px 24px rgba(0, 0, 0, .4);
}

[data-bs-theme="dark"] .login-mobile-logo {
    filter: invert(1);
}

/* contact form textarea height */
.site-contact textarea.form-control {
    height: 140px;
}

/* form cards */
.form-card {
    border-radius: 1rem;
    box-shadow: 0 4px 24px rgba(0, 0, 0, .10);
}

/* dark mode: elevate form cards against dark background */
[data-bs-theme="dark"] .form-card {
    box-shadow: 0 0 0 1px var(--bs-border-color), 0 4px 24px rgba(0, 0, 0, .4);
}

/* captcha: blend with card background */
.site-contact img[src*="captcha"] {
    border-radius: var(--bs-border-radius);
    mix-blend-mode: multiply;
}

/* dark mode: invert captcha for visibility on dark background */
[data-bs-theme="dark"] .site-contact img[src*="captcha"] {
    mix-blend-mode: screen;
    filter: invert(1) hue-rotate(180deg);
}

/* centered page layout */
.site-login,
.site-signup,
.site-contact,
.site-request-password-reset,
.site-reset-password,
.site-resend-verification-email,
.site-index,
.site-error,
.site-about {
    flex: 1;
}

.site-error .site-error-content,
.site-about .site-about-content {
    width: 100%;
    max-width: 90%;
}

@media (min-width: 576px) {
    .site-error .site-error-content,
    .site-about .site-about-content {
        max-width: 80%;
    }
}

@media (min-width: 768px) {
    .site-error .site-error-content,
    .site-about .site-about-content {
        max-width: 60%;
    }
}

@media (min-width: 992px) {
    .site-error .site-error-content,
    .site-about .site-about-content {
        max-width: 50%;
    }
}

/* hero banner */
.hero-banner {
    background: linear-gradient(135deg, #83C933 0%, #3a9cbd 40%, #40B3D8 100%);
    position: relative;
}

.hero-lead {
    max-width: 520px;
}

.hero-logo {
    height: 120px;
    opacity: .45;
    right: 2.5rem;
    top: 50%;
    transform: translateY(-50%);
}

.hero-banner::before {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: inherit;
    background:
        radial-gradient(circle at 15% 85%, rgba(241, 138, 42, .3) 0%, transparent 45%),
        radial-gradient(circle at 85% 15%, rgba(131, 201, 51, .25) 0%, transparent 40%),
        radial-gradient(ellipse at 50% 50%, rgba(64, 179, 216, .15) 0%, transparent 60%);
    pointer-events: none;
}

/* extension cards */
.extension-card {
    transition: transform .15s ease-in-out, box-shadow .15s ease-in-out;
}

.extension-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, .12) !important;
}

.extension-icon {
    font-size: 1.5rem;
    line-height: 1;
}

/* dark mode: extension cards */
[data-bs-theme="dark"] .extension-card {
    background-color: var(--bs-body-bg);
    box-shadow: 0 0 0 1px var(--bs-border-color), 0 2px 8px rgba(0, 0, 0, .3);
}

[data-bs-theme="dark"] .extension-card:hover {
    box-shadow: 0 0 0 1px var(--bs-border-color), 0 8px 24px rgba(0, 0, 0, .4) !important;
}

/* Account pages */
.block__account { width: 100%; }
.b_account--secret { overflow-wrap: anywhere; }

/* Author workspace */
.block__authoring { width: 100%; margin-bottom: 2rem; }
.b_authoring--title, .b_authoring--chapter { overflow-wrap: anywhere; }
.b_authoring--table { overflow-x: auto; }
.b_authoring--cover { display: block; max-width: 180px; max-height: 260px; margin-bottom: 1rem; }
.b_authoring--chapter { padding: .5rem 0; }
.b_authoring--actions { display: inline-flex; flex-wrap: wrap; gap: .5rem; margin-left: .5rem; }
.b_authoring--move { display: inline; }
.b_authoring--toolbar { display: flex; flex-wrap: wrap; gap: .5rem; margin-bottom: .75rem; }
.b_authoring--editor { min-height: 20rem; padding: 1rem; line-height: 1.7; overflow-wrap: anywhere; }
.b_authoring--text { max-width: 75ch; line-height: 1.7; overflow-wrap: anywhere; }
.b_authoring--revision { padding: 1rem 0; border-bottom: 1px solid var(--bs-border-color); }
.b_authoring--conflict { margin-top: 1rem; }
.b_authoring--conflict textarea { margin-bottom: 1rem; }

/* Public library and reader; LESS sources maintained alongside. */
.block__library { margin-bottom: 2rem; }
.b_library--section { margin: 2rem 0; }
.b_library--grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 250px), 1fr)); gap: 1rem; margin: 1rem 0; }
.b_library--card { min-width: 0; overflow-wrap: anywhere; }
.b_library--cover { display: block; width: 100%; height: 260px; object-fit: contain; }
.b_library--filters { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 220px), 1fr)); gap: 1rem; }
.b_library--actions { display: flex; flex-wrap: wrap; gap: 1rem; align-items: center; }
.b_library--shelf { margin: 1.5rem 0; padding: 1rem 0; border-bottom: 1px solid var(--bs-border-color); }
.b_library--subscription { margin: 1rem 0; }
.b_library--honeypot { display: none; }
.b_library--details { display: grid; grid-template-columns: minmax(0, 220px) minmax(0, 1fr); gap: 2rem; overflow-wrap: anywhere; }
.b_library--contents li { margin-bottom: .75rem; overflow-wrap: anywhere; }
.b_library--avatar { width: 64px; height: 64px; border-radius: 50%; display: grid; place-items: center; background: var(--bs-secondary-bg); font-size: 2rem; }
@media (max-width: 575px) { .b_library--details { grid-template-columns: minmax(0, 1fr); } }

.block__reader { max-width: 780px; margin: 0 auto 2rem; overflow-wrap: anywhere; }
.b_reader--settings { display: flex; flex-wrap: wrap; gap: 1rem; align-items: end; margin: 1.5rem 0; }
.b_reader--text { font-size: 20px; line-height: 1.7; padding: 1rem 0; }
.b_reader--navigation { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 1rem; margin-top: 2rem; }
.b_reader--contents { margin: 1rem 0; }
.b_reader--contents li { margin: .5rem 0; }
.b_reader--text [data-anchor] { scroll-margin-top: 5rem; }
.b_reader--text.__protected { user-select: none; }
.b_reader--status { font-size: .875rem; color: var(--bs-secondary-color); }
@media print { .b_reader--text.__protected { display: none; } }