/* =============================================
   DGaO-Proceedings — "Corporate Spectral"
   Sitewide v4 Design System
   Burgundy-Red (#862e42) · Outfit + Source Sans 3
   ============================================= */

/* ============================
   DESIGN TOKENS
   ============================ */

:root {
    /* Surfaces */
    --white:          #ffffff;
    --paper:          #fafaf8;
    --warm:           #f5f5f2;
    --border:         #e8e7e3;
    --border-light:   #f0efeb;

    /* Text hierarchy */
    --text:           #1a1d2e;
    --text-mid:       #3d4155;
    --text-muted:     #6b7280;
    --text-light:     #9ca3af;

    /* Accent — DGaO Burgundy */
    --accent:         #862e42;
    --accent-light:   #a33d55;
    --accent-pale:    #f5f0ee;
    --accent-dark:    #3a1520;
    --accent-glow:    rgba(134, 46, 66, 0.12);
    --accent-muted:   #b8878f;
    --accent-subtle:  #f5f0ee;

    /* Typography */
    --font-display:   'Outfit', 'Source Sans 3', system-ui, sans-serif;
    --font-body:      'Source Sans 3', 'Segoe UI', system-ui, sans-serif;
    --font-serif:     'Libre Baskerville', Georgia, serif;
    --font-mono:      'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;

    /* Easing */
    --ease:           cubic-bezier(0.22, 1, 0.36, 1);
    --spring:         cubic-bezier(0.34, 1.56, 0.64, 1);
    --smooth:         cubic-bezier(0.4, 0, 0.2, 1);

    /* Shadows — subtle, restrained */
    --shadow-sm:      0 1px 3px rgba(26, 29, 46, 0.04), 0 2px 6px rgba(26, 29, 46, 0.03);
    --shadow-md:      0 2px 6px rgba(26, 29, 46, 0.05), 0 6px 18px rgba(26, 29, 46, 0.05);
    --shadow-lg:      0 4px 8px rgba(26, 29, 46, 0.04), 0 12px 32px rgba(26, 29, 46, 0.07);

    /* Radius */
    --radius:         6px;
    --radius-sm:      4px;
    --radius-lg:      10px;

    /* Type scale */
    --text-xs:        0.72rem;
    --text-sm:        0.84rem;
    --text-base:      1rem;
    --text-md:        1.08rem;
    --text-lg:        1.25rem;
    --text-xl:        1.4rem;
    --text-2xl:       1.65rem;
    --text-3xl:       2.1rem;
    --text-4xl:       2.75rem;

    /* Legacy aliases (for any templates referencing old tokens) */
    --bg:             var(--white);
    --bg-card:        var(--white);
    --bg-subtle:      var(--paper);
    --font-sans:      var(--font-display);

    /* v4 aliases — used by homepage template */
    --v4-white:        var(--white);
    --v4-paper:        var(--paper);
    --v4-warm:         var(--warm);
    --v4-border:       var(--border);
    --v4-border-light: var(--border-light);
    --v4-text:         var(--text);
    --v4-text-mid:     var(--text-mid);
    --v4-text-muted:   var(--text-muted);
    --v4-text-light:   var(--text-light);
    --v4-accent:       var(--accent);
    --v4-accent-light: var(--accent-light);
    --v4-accent-pale:  var(--accent-pale);
    --v4-accent-dark:  var(--accent-dark);
    --v4-accent-glow:  var(--accent-glow);
    --v4-accent-muted: var(--accent-muted);
    --v4-font:         var(--font-display);
    --v4-body:         var(--font-body);
    --v4-serif:        var(--font-serif);
    --v4-ease:         var(--ease);
    --v4-spring:       var(--spring);
    --v4-smooth:       var(--smooth);

    /* Bootstrap overrides */
    --bs-body-bg:               var(--white);
    --bs-body-color:            var(--text);
    --bs-body-font-family:      var(--font-body);
    --bs-primary:               var(--accent);
    --bs-primary-rgb:           134, 46, 66;
    --bs-secondary:             var(--text-muted);
    --bs-secondary-rgb:         107, 114, 128;
    --bs-border-color:          var(--border);
    --bs-border-radius:         6px;
    --bs-border-radius-sm:      4px;
    --bs-border-radius-lg:      10px;
    --bs-border-radius-pill:    50rem;
    --bs-focus-ring-color:      rgba(134, 46, 66, 0.18);
    --bs-link-color:            var(--accent);
    --bs-link-color-rgb:        134, 46, 66;
    --bs-link-hover-color:      var(--accent-light);
    --bs-link-hover-color-rgb:  163, 61, 85;
    --bs-card-bg:               var(--white);
    --bs-card-border-color:     var(--border-light);
}


/* ============================
   BASE
   ============================ */

body {
    font-family: var(--font-body);
    color: var(--text);
    background-color: var(--white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: clip;
}

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

h1, h2, h3, h4, h5, h6,
.h1, .h2, .h3, .h4, .h5, .h6 {
    font-family: var(--font-display);
    color: var(--text);
    font-weight: 600;
    letter-spacing: -0.01em;
}


/* ============================
   LAYOUT
   ============================ */

.container-narrow {
    max-width: 960px;
}


/* ============================
   SITE HEADER — two-row, editorial
   Row 1: brand + utility (small, ruhig)
   Row 2: primary nav (groß, klar, mit Hover-Underline)
   ============================ */

.skip-link {
    position: absolute;
    top: 0; left: 0;
    background: var(--accent);
    color: #fff;
    padding: 0.5rem 1rem;
    font-family: var(--font-display);
    font-weight: 600;
    z-index: 100;
}
.skip-link:not(:focus):not(:focus-within) {
    clip: rect(0 0 0 0);
    clip-path: inset(50%);
    height: 1px; width: 1px;
    overflow: hidden;
    white-space: nowrap;
}

.site-header {
    position: relative;
    z-index: 5;
    background: var(--white);
}

.site-header__inner {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
}

/* Row 1 — top */
.site-header__top {
    border-bottom: 1px solid var(--border-light);
}

.site-header__top .site-header__inner {
    min-height: 64px;
}

/* Brand wordmark */
.site-brand {
    display: inline-flex;
    align-items: baseline;
    gap: 0.4rem;
    text-decoration: none;
    font-family: var(--font-display);
    line-height: 1;
    flex-wrap: wrap;
}

.site-brand:hover { text-decoration: none; }

.site-brand__mark {
    font-size: 1.55rem;
    font-weight: 800;
    color: var(--accent);
    letter-spacing: -0.025em;
}

.site-brand__sep {
    color: var(--accent-muted);
    font-size: 1.1rem;
    font-weight: 400;
}

.site-brand__tail {
    font-size: 1.55rem;
    font-weight: 400;
    color: var(--text);
    letter-spacing: -0.015em;
}

.site-brand__issn {
    display: inline-block;
    margin-left: 0.7rem;
    padding-left: 0.7rem;
    border-left: 1px solid var(--border);
    font-family: var(--font-body);
    font-size: 0.66rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-light);
    align-self: center;
    line-height: 1.2;
}

@media (max-width: 575.98px) {
    .site-brand__issn { display: none; }
    .site-brand__mark, .site-brand__tail { font-size: 1.25rem; }
    .site-header__top .site-header__inner { min-height: 56px; }
}

/* Utility (right side row 1) */
.site-header__util {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    font-family: var(--font-display);
    font-size: 0.86rem;
}

.site-util-link {
    color: var(--text-mid);
    text-decoration: none;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    padding: 0.4rem 0.2rem;
    transition: color 0.18s var(--ease);
}

.site-util-link .bi { font-size: 0.95em; opacity: 0.8; }

.site-util-link:hover {
    color: var(--accent);
    text-decoration: none;
}

/* Row 2 — primary nav */
.site-nav2 {
    border-bottom: 1px solid var(--border-light);
    background: var(--white);
}

.site-nav2__inner {
    min-height: 56px;
    justify-content: flex-start;
    gap: 0;
    flex-wrap: wrap;
}

.site-nav2__list {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    gap: 0;
    align-items: stretch;
    flex-wrap: wrap;
}

.site-nav2__link {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    font-family: var(--font-display);
    font-size: 0.98rem;
    font-weight: 500;
    color: var(--text);
    text-decoration: none;
    padding: 1.05rem 1.4rem;
    border-bottom: 3px solid transparent;
    margin-bottom: -1px;
    transition: color 0.18s var(--ease),
                border-color 0.18s var(--ease);
}

.site-nav2__link:first-child { padding-left: 0; }

.site-nav2__list > li:first-child .site-nav2__link {
    padding-left: 0;
}

.site-nav2__link .bi {
    font-size: 0.95em;
    opacity: 0.7;
}

.site-nav2__link:hover {
    color: var(--accent);
    text-decoration: none;
    border-bottom-color: var(--accent-muted);
}

.site-nav2__link:hover .bi { opacity: 1; }

.site-nav2__link.is-active {
    color: var(--accent);
    font-weight: 600;
    border-bottom-color: var(--accent);
}

/* Mobile toggle */
.site-nav2__toggle {
    display: none;
    background: none;
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 0.5rem 0.6rem;
    cursor: pointer;
}

.site-nav2__toggle-icon {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--text);
    position: relative;
}
.site-nav2__toggle-icon::before,
.site-nav2__toggle-icon::after {
    content: '';
    position: absolute;
    left: 0;
    width: 22px;
    height: 2px;
    background: var(--text);
}
.site-nav2__toggle-icon::before { top: -7px; }
.site-nav2__toggle-icon::after  { top: 7px; }

@media (max-width: 767.98px) {
    .site-nav2__toggle { display: inline-flex; margin: 0.6rem 0; }
    .site-nav2__list {
        flex-direction: column;
        flex-basis: 100%;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s var(--ease);
    }
    .site-nav2__list.is-open { max-height: 320px; }
    .site-nav2__link {
        padding: 0.85rem 0;
        border-bottom: 1px solid var(--border-light);
        margin-bottom: 0;
        width: 100%;
    }
    .site-nav2__link.is-active { border-bottom-color: var(--accent); }
}


/* ============================
   FOOTER — Dark burgundy with converging stripes
   ============================ */

.site-footer {
    background: var(--accent-dark);
    border-top: 3px solid var(--accent);
    border-image: none;
    color: rgba(255, 255, 255, 0.5);
    font-family: var(--font-display);
    font-size: var(--text-xs);
    position: relative;
    z-index: 2;
    overflow: hidden;
}

/* Converging white stripe fan — corporate slide pattern */
.site-footer::before {
    content: '';
    position: absolute;
    inset: 0;
    pointer-events: none;
    background:
        linear-gradient(52deg, transparent 0%, transparent 49.6%, rgba(255,255,255,0.07) 49.6%, rgba(255,255,255,0.07) 50%, transparent 50%, transparent 100%),
        linear-gradient(58deg, transparent 0%, transparent 49.6%, rgba(255,255,255,0.06) 49.6%, rgba(255,255,255,0.06) 50.1%, transparent 50.1%, transparent 100%),
        linear-gradient(45deg, transparent 0%, transparent 49.7%, rgba(255,255,255,0.08) 49.7%, rgba(255,255,255,0.08) 50%, transparent 50%, transparent 100%),
        linear-gradient(64deg, transparent 0%, transparent 49.5%, rgba(255,255,255,0.055) 49.5%, rgba(255,255,255,0.055) 50.1%, transparent 50.1%, transparent 100%),
        linear-gradient(38deg, transparent 0%, transparent 49.6%, rgba(255,255,255,0.09) 49.6%, rgba(255,255,255,0.09) 49.9%, transparent 49.9%, transparent 100%),
        linear-gradient(70deg, transparent 0%, transparent 49.6%, rgba(255,255,255,0.045) 49.6%, rgba(255,255,255,0.045) 50.2%, transparent 50.2%, transparent 100%),
        linear-gradient(33deg, transparent 0%, transparent 49.7%, rgba(255,255,255,0.07) 49.7%, rgba(255,255,255,0.07) 50%, transparent 50%, transparent 100%);
    transform-origin: bottom left;
}

.site-footer a {
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
    transition: color 0.2s;
    position: relative;
    z-index: 1;
}

.site-footer a:hover {
    color: #ffffff;
}

.site-footer .container,
.site-footer .container-narrow {
    position: relative;
    z-index: 1;
}


/* ============================
   SECTION BACKGROUNDS
   ============================ */

.section-hero {
    background: var(--paper);
    border-bottom: 1px solid var(--border-light);
}

.section-search {
    background: var(--white);
    border-bottom: 1px solid var(--border-light);
}

.section-conferences {
    background: var(--paper);
    border-bottom: 1px solid var(--border-light);
}

.section-archive {
    background: var(--white);
    padding-bottom: 2rem;
}


/* ============================
   HERO BANNER (sub-pages)
   ============================ */

.hero-banner {
    background: var(--accent);
    border-bottom: none;
    padding: 2.5rem 0 2rem;
}

.hero-title {
    font-family: var(--font-display);
    font-size: var(--text-3xl);
    font-weight: 700;
    color: #ffffff;
    margin: 0;
    position: relative;
    letter-spacing: -0.02em;
}

.hero-subtitle {
    font-family: var(--font-display);
    font-size: var(--text-sm);
    color: rgba(255, 255, 255, 0.7);
    margin: 0.75rem 0 0;
    position: relative;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.hero-description {
    font-family: var(--font-body);
    font-size: var(--text-base);
    color: rgba(255, 255, 255, 0.85);
    margin: 0.5rem 0 0;
    position: relative;
    font-style: italic;
}


/* ============================
   HOMEPAGE HERO
   ============================ */

.hero-home-title {
    font-family: var(--font-display);
    font-size: var(--text-4xl);
    font-weight: 800;
    color: var(--text);
    letter-spacing: -0.03em;
    margin-bottom: 0.25rem;
}

.hero-home-issn {
    font-family: var(--font-display);
    font-size: var(--text-xs);
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 0.25rem;
}

.hero-home-tagline {
    font-family: var(--font-body);
    font-size: var(--text-base);
    color: var(--text-muted);
    font-style: italic;
    margin-bottom: 0;
}


/* ============================
   STATS BAR
   ============================ */

.stats-bar {
    display: flex;
    justify-content: center;
    gap: 3rem;
    padding: 1.5rem 0;
    border-top: 3px solid var(--accent);
    border-bottom: 1px solid var(--border-light);
    background: var(--white);
}

.stats-bar--full {
    margin-left: calc(-0.75rem - 1px);
    margin-right: calc(-0.75rem - 1px);
    margin-top: 0;
    margin-bottom: 2rem;
}

.stats-bar .stat-item {
    text-align: center;
}

.stats-bar .stat-number {
    display: block;
    font-family: var(--font-display);
    font-size: var(--text-3xl);
    font-weight: 800;
    color: var(--text);
    line-height: 1;
    letter-spacing: -0.03em;
}

.stats-bar .stat-label {
    display: block;
    font-family: var(--font-display);
    font-size: var(--text-xs);
    font-weight: 600;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-top: 0.25rem;
}

.stats-bar .stat-icon {
    display: block;
    font-size: var(--text-lg);
    color: var(--accent);
    margin-bottom: 0.3rem;
}

.stats-bar--hero {
    border-top: none;
    border-bottom: none;
    background: transparent;
    margin-top: 1.5rem;
    margin-bottom: 0;
    padding: 1rem 0 0;
}


/* ============================
   SECTION HEADINGS
   ============================ */

.section-heading {
    font-family: var(--font-display);
    font-size: var(--text-lg);
    font-weight: 700;
    color: var(--text);
    padding-bottom: 0.5rem;
    border-bottom: 3px solid var(--accent);
    margin-bottom: 1.25rem;
    display: inline-block;
    letter-spacing: -0.01em;
}


/* ============================
   PAPER CARDS
   ============================ */

.paper-card {
    background: var(--white);
    border: 1px solid var(--border);
    border-left: 3px solid var(--accent);
    border-radius: var(--radius);
    padding: 1.25rem 1.5rem;
    transition: box-shadow 0.25s var(--ease),
                border-color 0.25s var(--ease),
                transform 0.25s var(--ease);
}

.paper-card:hover {
    box-shadow: var(--shadow-md);
    border-left-color: var(--accent-light);
    transform: translateY(-1px);
}

.paper-card .card-eyebrow {
    font-family: var(--font-display);
    font-size: var(--text-xs);
    font-weight: 600;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 0.4rem;
}

.paper-card .card-title {
    font-family: var(--font-display);
    font-size: var(--text-md);
    font-weight: 600;
    color: var(--text);
    line-height: 1.4;
    margin-bottom: 0.35rem;
    letter-spacing: -0.005em;
}

.paper-card .card-authors {
    font-family: var(--font-body);
    font-size: var(--text-sm);
    color: var(--text-muted);
    line-height: 1.45;
}

.paper-card .card-footer-bar {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-top: 0.75rem;
    padding-top: 0.55rem;
    border-top: 1px solid var(--border-light);
    font-size: var(--text-xs);
}

.text-clamp-2 {
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}


/* ============================
   TYPE BADGES
   ============================ */

.badge-hauptvortrag  { background: #fdf6e3; color: #7c5e10; font-weight: 600; }
.badge-sondervortrag { background: #f0e6f6; color: #5b2d7a; font-weight: 600; }
.badge-poster        { background: #e6f4ea; color: #1a6b34; font-weight: 600; }
.badge-vortrag       { background: #e8f0fe; color: #1a4ea0; font-weight: 600; }

.badge-pdf {
    background: var(--accent-pale);
    color: var(--accent);
    font-weight: 600;
}

.badge-count {
    background: var(--accent-pale);
    color: var(--accent);
    border: 1px solid transparent;
    font-family: var(--font-display);
    font-weight: 600;
    font-size: var(--text-xs);
    transition: background 0.2s var(--ease), color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.badge-count-new {
    background: transparent;
    color: var(--accent);
    font-weight: 700;
    font-size: var(--text-sm);
    font-family: var(--font-display);
}


/* ============================
   ARCHIVE LIST
   ============================ */

.v4-archive-list {
    list-style: none;
    margin: 0;
    padding: 0;
}

.v4-archive-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.8rem 1rem;
    border-left: 3px solid transparent;
    border-bottom: 1px solid var(--border-light);
    text-decoration: none;
    color: var(--text);
    transition: all 0.22s var(--ease);
}

.v4-archive-item:first-child {
    border-top: 1px solid var(--border-light);
}

.v4-archive-item:hover {
    background: var(--accent-pale);
    border-left-color: var(--accent);
    text-decoration: none;
    color: var(--text);
}

.v4-archive-year {
    font-family: var(--font-display);
    font-size: 1.02rem;
    font-weight: 700;
    color: var(--text);
    min-width: 48px;
    flex-shrink: 0;
}

.v4-archive-loc {
    font-family: var(--font-body);
    font-size: 0.86rem;
    color: var(--text-muted);
    flex: 1;
    margin-left: 0.85rem;
}

.v4-archive-loc strong {
    font-family: var(--font-display);
    font-weight: 600;
    color: var(--text);
}

.v4-archive-nr {
    font-family: var(--font-display);
    font-size: 0.72rem;
    color: var(--text-light);
    margin-left: 0.5rem;
}

.v4-archive-badge {
    font-family: var(--font-display);
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--accent);
    background: var(--accent-pale);
    border-radius: 20px;
    padding: 0.15rem 0.6rem;
    flex-shrink: 0;
    margin-left: 1rem;
    transition: background 0.2s, color 0.2s;
}

.v4-archive-item:hover .v4-archive-badge {
    background: var(--accent);
    color: var(--white);
}

.v4-archive-more {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    font-family: var(--font-display);
    font-size: 0.86rem;
    font-weight: 600;
    color: var(--accent);
    text-decoration: none;
    margin-top: 1.15rem;
    transition: color 0.2s;
}

.v4-archive-more:hover {
    color: var(--accent-light);
    text-decoration: none;
}


/* ============================
   AUTHOR INDEX
   ============================ */

.letter-header {
    position: sticky;
    top: 0;
    background: var(--white);
    z-index: 10;
    padding: 0.3rem 0;
    font-family: var(--font-display);
    font-weight: 700;
    border-bottom: 2px solid var(--accent);
    margin-bottom: 0.6rem;
}


/* ============================
   SEARCH
   ============================ */

.search-input {
    border-color: var(--border);
    border-radius: var(--radius);
    font-family: var(--font-display);
    font-size: var(--text-base);
    padding: 0.65rem 1rem;
    transition: border-color 0.25s var(--ease),
                box-shadow 0.25s var(--ease);
}

.search-input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.search-input::placeholder {
    color: var(--text-light);
    font-weight: 400;
}

.max-w-search {
    max-width: 560px;
}

/* Integrated search (homepage) */
.search-form-integrated {
    max-width: 640px;
}

.search-input-group {
    position: relative;
    display: flex;
    align-items: center;
    background: var(--white);
    border: 2px solid var(--border);
    border-radius: var(--radius-lg);
    transition: border-color 0.3s var(--ease),
                box-shadow 0.3s var(--ease),
                transform 0.25s var(--ease);
    overflow: hidden;
}

.search-input-group:focus-within {
    border-color: var(--accent);
    transform: scale(1.005);
    box-shadow: 0 2px 16px rgba(134, 46, 66, 0.08),
                0 0 0 3px rgba(134, 46, 66, 0.06);
}

.search-input-icon {
    position: absolute;
    left: 1.1rem;
    color: var(--text-light);
    font-size: var(--text-md);
    pointer-events: none;
    z-index: 1;
    transition: color 0.25s;
}

.search-input-group:focus-within .search-input-icon {
    color: var(--accent);
}

.search-input-integrated {
    border: none;
    background: transparent;
    padding: 0.9rem 1rem 0.9rem 2.85rem;
    font-family: var(--font-display);
    font-size: 0.95rem;
    font-weight: 400;
    color: var(--text);
    flex: 1;
    min-width: 0;
}

.search-input-integrated:focus {
    box-shadow: none;
    outline: none;
}

.search-input-integrated::placeholder {
    color: var(--text-light);
    font-weight: 400;
}

.search-submit-btn {
    border-radius: 0;
    border: none;
    border-left: 1px solid var(--border-light);
    padding: 0.9rem 1.4rem;
    white-space: nowrap;
    font-family: var(--font-display);
    font-weight: 600;
    font-size: var(--text-sm);
    background: var(--accent);
    color: var(--white);
    transition: background 0.2s;
}

.search-submit-btn:hover {
    background: var(--accent-light);
    color: var(--white);
}


/* ============================
   ARTICLE DETAIL
   ============================ */

.article-detail {
    background: var(--white);
    border: 1px solid var(--border-light);
    border-left: 4px solid var(--accent);
    border-radius: var(--radius);
    padding: 2.5rem;
}

.article-detail h1 {
    font-family: var(--font-display);
    font-size: var(--text-xl);
    font-weight: 700;
    line-height: 1.35;
    letter-spacing: -0.015em;
    max-width: 54ch;
}

.article-detail .article-meta {
    font-family: var(--font-body);
    font-size: var(--text-sm);
    color: var(--text-muted);
    padding-bottom: 1rem;
    margin-bottom: 1.5rem;
    border-bottom: 1px solid var(--border-light);
}

.article-detail .abstract-block {
    border-left: 3px solid var(--accent-muted);
    padding-left: 1.5rem;
    color: var(--text-mid);
    font-family: var(--font-body);
    line-height: 1.75;
    max-width: 68ch;
}

.article-detail .abstract-block p {
    white-space: pre-line;
}

.article-detail .keyword-badge {
    background: var(--paper);
    color: var(--text-mid);
    border: 1px solid var(--border);
    font-family: var(--font-display);
    font-size: var(--text-sm);
    font-weight: 500;
    transition: background 0.15s, color 0.15s;
}

.article-detail .keyword-badge:hover {
    background: var(--accent-pale);
    color: var(--accent);
    border-color: var(--accent-muted);
}


/* ============================
   BIBTEX
   ============================ */

.bibtex-block {
    font-family: var(--font-mono);
    font-size: var(--text-sm);
    background: var(--paper);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 1.1rem 1.25rem;
    white-space: pre-wrap;
    word-break: break-all;
    color: var(--text-mid);
    line-height: 1.6;
}


/* ============================
   SORT BUTTONS
   ============================ */

.sort-btn {
    font-family: var(--font-display);
    font-size: var(--text-sm);
    font-weight: 500;
    transition: color 0.2s, border-color 0.2s;
}

.sort-btn.active {
    font-weight: 600;
    color: var(--accent);
    border-color: var(--accent);
}

.sort-btn:hover:not(.active) {
    color: var(--text-mid);
    border-color: var(--text-light);
}


/* ============================
   BUTTONS
   ============================ */

.btn-accent {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
    font-family: var(--font-display);
    font-weight: 600;
    transition: background 0.2s var(--ease),
                transform 0.15s var(--ease);
}

.btn-accent:hover {
    background: var(--accent-light);
    border-color: var(--accent-light);
    color: #fff;
    transform: translateY(-1px);
}

.btn-outline-accent {
    color: var(--accent);
    border-color: var(--accent);
    font-family: var(--font-display);
    font-weight: 600;
    transition: all 0.2s var(--ease);
}

.btn-outline-accent:hover {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
}


/* ============================
   CONFERENCE CARDS
   ============================ */

.conference-card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    position: relative;
    display: flex;
    flex-direction: column;
    transition: transform 0.3s var(--ease),
                box-shadow 0.3s var(--ease);
}

/* Red top accent bar */
.conference-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 3px;
    background: var(--accent);
    z-index: 1;
}

.conference-card:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.conference-card-img-link {
    display: block;
    overflow: hidden;
    border-bottom: 1px solid var(--border-light);
    line-height: 0;
}

.conference-card-img {
    width: 100%;
    height: auto;
    display: block;
}

.conference-card-body {
    padding: 1.25rem 1.5rem 1.5rem;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.conference-card-title {
    font-family: var(--font-display);
    font-size: var(--text-md);
    font-weight: 600;
    margin-bottom: 0.5rem;
    letter-spacing: -0.005em;
}

.conference-card-text {
    font-family: var(--font-body);
    font-size: var(--text-sm);
    color: var(--text-muted);
    flex: 1;
    margin-bottom: 0.75rem;
    line-height: 1.55;
}

/* Legacy banner (if used) */
.conference-banner img {
    display: block;
}


/* ============================
   LINKS
   ============================ */

a.text-decoration-none:hover {
    text-decoration: underline !important;
}

a.accent-link {
    color: var(--accent);
    text-decoration: underline;
    text-decoration-color: var(--accent-muted);
    text-underline-offset: 0.18em;
    transition: color 0.2s var(--ease),
                text-decoration-color 0.2s var(--ease);
}

a.accent-link:hover {
    color: var(--accent-light);
    text-decoration-color: var(--accent-light);
}


/* ============================
   BREADCRUMB
   ============================ */

.breadcrumb {
    font-family: var(--font-display);
    font-size: var(--text-sm);
}

.breadcrumb-item a {
    color: var(--accent);
    transition: color 0.15s;
}

.breadcrumb-item a:hover {
    color: var(--accent-light);
}

.breadcrumb-item.active {
    color: var(--text-muted);
}


/* ============================
   STAT CARDS (Statistik page)
   ============================ */

.stat-card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.stat-card .card-header {
    font-family: var(--font-display);
    font-weight: 600;
    background: var(--paper);
    border-bottom: 1px solid var(--border-light);
}

.stat-card .table {
    font-family: var(--font-body);
    font-size: var(--text-sm);
}

.stat-card .table th {
    font-family: var(--font-display);
    font-weight: 600;
    font-size: var(--text-xs);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
}

.stat-card .table-hover tbody tr:hover {
    background: var(--accent-pale);
}


/* ============================
   KEYFRAMES
   ============================ */

@keyframes v4-fadeUp {
    from { opacity: 0; transform: translateY(24px); }
    to   { opacity: 1; transform: translateY(0); }
}

@keyframes v4-fadeIn {
    from { opacity: 0; }
    to   { opacity: 1; }
}



/* ============================
   V4 ANIMATION UTILITIES
   ============================ */

/* Entry animations */
.v4-anim {
    opacity: 0;
    animation: v4-fadeUp 0.6s var(--ease) forwards;
}
.v4-d1 { animation-delay: 0.05s; }
.v4-d2 { animation-delay: 0.12s; }
.v4-d3 { animation-delay: 0.19s; }
.v4-d4 { animation-delay: 0.26s; }
.v4-d5 { animation-delay: 0.33s; }
.v4-d6 { animation-delay: 0.40s; }

/* Scroll reveal — disabled for academic journal professionalism.
   Content is immediately visible; no fade-in-on-scroll. */
.v4-reveal {
    opacity: 1;
    transform: none;
}

.v4-rd1 { transition-delay: 0.04s; }
.v4-rd2 { transition-delay: 0.08s; }
.v4-rd3 { transition-delay: 0.12s; }
.v4-rd4 { transition-delay: 0.16s; }
.v4-rd5 { transition-delay: 0.20s; }


/* ============================
   RESPONSIVE — TABLET
   ============================ */

@media (max-width: 767.98px) {
    .hero-title {
        font-size: var(--text-2xl);
    }

    .hero-home-title {
        font-size: var(--text-3xl);
    }

    .article-detail {
        padding: 1.75rem;
    }

    .stats-bar {
        gap: 2rem;
        flex-wrap: wrap;
    }

    .stats-bar .stat-number {
        font-size: var(--text-xl);
    }

    .search-form-integrated {
        max-width: 100%;
    }

    .conference-card {
        max-width: 400px;
        margin-left: auto;
        margin-right: auto;
    }

    .search-input-group {
        flex-direction: column;
        border-radius: var(--radius-lg);
    }

    .search-input-integrated {
        width: 100%;
        padding: 0.9rem 1rem 0.9rem 2.85rem;
    }

    .search-submit-btn {
        width: 100%;
        text-align: center;
        display: flex;
        justify-content: center;
        border-left: none;
        border-top: 1px solid var(--border-light);
    }
}


/* ============================
   RESPONSIVE — MOBILE
   ============================ */

@media (max-width: 575.98px) {
    .hero-title {
        font-size: var(--text-xl);
    }

    .hero-home-title {
        font-size: var(--text-2xl);
    }

    .hero-subtitle {
        font-size: var(--text-xs);
    }

    .stats-bar {
        gap: 1.25rem;
    }

    .stats-bar .stat-number {
        font-size: var(--text-xl);
    }

    .stats-bar--hero {
        gap: 1.5rem;
    }

    .article-detail {
        padding: 1.25rem;
        border-left-width: 3px;
    }

    .header-logo-img {
        height: 34px;
    }

    .paper-card {
        padding: 1rem 1.15rem;
    }

    .v4-archive-item {
        padding: 0.7rem 0.75rem;
    }

    .v4-archive-loc {
        font-size: 0.8rem;
    }

    .search-form-integrated {
        max-width: 100%;
    }

    .search-submit-btn {
        padding: 0.85rem 0.75rem;
        font-size: var(--text-sm);
    }
}


/* ============================
   REDUCED MOTION (Accessibility)
   ============================ */

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}