/* quicksand-300 - latin */
@font-face {
    font-family: 'Quicksand';
    font-style: normal;
    font-weight: 300;
    src: url('../vendor/googlefonts/quicksand-v28-latin-300.eot');
    src: local(''),
       url('../vendor/googlefonts/quicksand-v28-latin-300.eot?#iefix') format('embedded-opentype'),
       url('../vendor/googlefonts/quicksand-v28-latin-300.woff2') format('woff2'),
       url('../vendor/googlefonts/quicksand-v28-latin-300.woff') format('woff'),
       url('../vendor/googlefonts/quicksand-v28-latin-300.ttf') format('truetype'),
       url('../vendor/googlefonts/quicksand-v28-latin-300.svg#Quicksand') format('svg');
}

/* quicksand-regular - latin */
@font-face {
    font-family: 'Quicksand';
    font-style: normal;
    font-weight: 400;
    src: url('../vendor/googlefonts/quicksand-v28-latin-regular.eot');
    src: local(''),
       url('../vendor/googlefonts/quicksand-v28-latin-regular.eot?#iefix') format('embedded-opentype'),
       url('../vendor/googlefonts/quicksand-v28-latin-regular.woff2') format('woff2'),
       url('../vendor/googlefonts/quicksand-v28-latin-regular.woff') format('woff'),
       url('../vendor/googlefonts/quicksand-v28-latin-regular.ttf') format('truetype'),
       url('../vendor/googlefonts/quicksand-v28-latin-regular.svg#Quicksand') format('svg');
}

/* quicksand-500 - latin */
@font-face {
    font-family: 'Quicksand';
    font-style: normal;
    font-weight: 500;
    src: url('../vendor/googlefonts/quicksand-v28-latin-500.eot');
    src: local(''),
       url('../vendor/googlefonts/quicksand-v28-latin-500.eot?#iefix') format('embedded-opentype'),
       url('../vendor/googlefonts/quicksand-v28-latin-500.woff2') format('woff2'),
       url('../vendor/googlefonts/quicksand-v28-latin-500.woff') format('woff'),
       url('../vendor/googlefonts/quicksand-v28-latin-500.ttf') format('truetype'),
       url('../vendor/googlefonts/quicksand-v28-latin-500.svg#Quicksand') format('svg');
}

/* quicksand-600 - latin */
@font-face {
    font-family: 'Quicksand';
    font-style: normal;
    font-weight: 600;
    src: url('../vendor/googlefonts/quicksand-v28-latin-600.eot');
    src: local(''),
       url('../vendor/googlefonts/quicksand-v28-latin-600.eot?#iefix') format('embedded-opentype'),
       url('../vendor/googlefonts/quicksand-v28-latin-600.woff2') format('woff2'),
       url('../vendor/googlefonts/quicksand-v28-latin-600.woff') format('woff'),
       url('../vendor/googlefonts/quicksand-v28-latin-600.ttf') format('truetype'),
       url('../vendor/googlefonts/quicksand-v28-latin-600.svg#Quicksand') format('svg');
}

/* quicksand-700 - latin */
@font-face {
    font-family: 'Quicksand';
    font-style: normal;
    font-weight: 700;
    src: url('../vendor/googlefonts/quicksand-v28-latin-700.eot');
    src: local(''),
       url('../vendor/googlefonts/quicksand-v28-latin-700.eot?#iefix') format('embedded-opentype'),
       url('../vendor/googlefonts/quicksand-v28-latin-700.woff2') format('woff2'),
       url('../vendor/googlefonts/quicksand-v28-latin-700.woff') format('woff'),
       url('../vendor/googlefonts/quicksand-v28-latin-700.ttf') format('truetype'),
       url('../vendor/googlefonts/quicksand-v28-latin-700.svg#Quicksand') format('svg');
}

/* ─── CSS Variables ─── */
:root {
    --bg: #ffffff;
    --surface: #f5f5f5;
    --card: #fafafa;
    --border: #d0d0d0;
    --accent: #000000;
    --accent2: #444444;
    --accent3: #000000;
    --text: #0a0a0a;
    --muted: #999999;
    --label: #555555;
    --danger: #1a1a1a;
    --success: #000000;
}

* {
    box-sizing: border-box;
}

/* ─── Body ─── */
body {
    min-height: 100vh;
    margin: 0;
    background-color: var(--bg);
    color: var(--text);
    font-family: 'Quicksand', sans-serif;
    font-weight: 400;
    overflow-x: hidden;
}

/* Background grid pattern */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    background-image:
        linear-gradient(rgba(0,0,0,0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0,0,0,0.05) 1px, transparent 1px);
    background-size: 40px 40px;
    pointer-events: none;
    z-index: 0;
}

/* Ambient glow */
body::after {
    content: '';
    position: fixed;
    top: -20%;
    left: 50%;
    transform: translateX(-50%);
    width: 800px;
    height: 400px;
    background: radial-gradient(ellipse, rgba(0,0,0,0.03) 0%, transparent 70%);
    pointer-events: none;
    z-index: 0;
}

.container {
    position: relative;
    z-index: 1;
}

/* ─── Links ─── */
a:link,
a:visited {
    color: var(--text);
    text-decoration: underline;
}

a:hover {
    color: var(--muted);
    text-decoration: underline;
}

a:active {
    color: var(--text);
    text-decoration: underline;
}

/* ─── Nav ─── */
nav {
    padding: 24px 0 0;
}

.navbar {
    background: transparent !important;
    padding: 0;
}

.navbar-nav .nav-link {
    font-family: 'Quicksand', sans-serif;
    font-size: 13px;
    font-weight: 500;
    color: var(--muted) !important;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    text-decoration: none;
    padding: 6px 14px;
    border-radius: 6px;
    transition: color 0.2s ease, background 0.2s ease;
}

.navbar-nav .nav-link:hover {
    color: var(--text) !important;
    background: rgba(0, 0, 0, 0.06);
    text-decoration: none;
}

.navbar-nav .nav-link.active {
    color: var(--accent) !important;
    text-decoration: none;
    font-weight: 600;
}

.navbar-toggler {
    border-color: rgba(0,0,0,0.3);
}

.navbar-toggler-icon {
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='rgba(0,0,0,0.8)' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
}

/* ─── Header ─── */
header {
    padding: 40px 0 28px;
    border-bottom: 1px solid var(--border);
    margin-bottom: 40px;
    text-align: left;
}

h1 {
    font-family: 'Quicksand', sans-serif;
    font-size: clamp(28px, 5vw, 52px);
    font-weight: 700;
    line-height: 1.1;
    letter-spacing: -0.02em;
    color: var(--text);
    margin-bottom: 12px;
}

blockquote {
    font-style: italic;
    font-size: 16px;
    color: var(--muted);
    line-height: 1.6;
    border-left: 3px solid var(--border);
    padding-left: 16px;
    margin: 12px 0 8px;
}

cite {
    font-size: 12px;
    color: var(--muted);
    letter-spacing: 0.04em;
}

cite a:link,
cite a:visited {
    color: var(--muted);
}

/* ─── Main ─── */
main {
    padding: 0 0 40px;
}

h2 {
    font-family: 'Quicksand', sans-serif;
    font-size: 18px;
    font-weight: 700;
    color: var(--text);
    margin-top: 24px;
    margin-bottom: 10px;
    letter-spacing: -0.01em;
}

p {
    font-size: 14px;
    color: var(--label);
    line-height: 1.7;
    margin-bottom: 12px;
}

address {
    font-size: 14px;
    color: var(--label);
    line-height: 1.8;
    font-style: normal;
    margin-bottom: 12px;
}

/* ─── Footer ─── */
footer {
    margin-top: 48px;
    padding: 20px 0;
    border-top: 1px solid var(--border);
    font-size: 12px;
    color: var(--muted);
    letter-spacing: 0.04em;
}

.social {
    text-align: left;
}

.copyright {
    text-align: right;
}

.copyright a:link,
.copyright a:visited {
    color: var(--muted);
}

footer a {
    margin-right: 5px;
}

/* ─── Active nav marker ─── */
.active {
    font-weight: 600;
}

/* ─── Hover-Dropdown ─── */
.navbar-nav .dropdown-menu {
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--card);
    padding: 4px;
    margin-top: 0;
    box-shadow: 0 8px 24px rgba(0,0,0,0.1);
}

.navbar-nav .dropdown-item {
    font-family: 'Quicksand', sans-serif;
    font-size: 13px;
    font-weight: 500;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    border-radius: 6px;
    padding: 7px 14px;
    text-decoration: none;
}

.navbar-nav .dropdown-item:hover {
    color: var(--text);
    background: rgba(0,0,0,0.06);
}

.navbar-nav .dropdown-item.active {
    color: var(--accent);
    background: transparent;
}

@media (min-width: 992px) {
    .navbar-nav .dropdown:hover .dropdown-menu {
        display: block;
    }
}

/* ═══════════════════════════════════════════════
   CALCULATOR STYLES (Vakuum-Rechner / Datum-Rechner)
   ═══════════════════════════════════════════════ */

/* CALCULATOR HEADER */
.header-inner {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 24px;
}

.logo-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(0,0,0,0.06);
    border: 1px solid rgba(0,0,0,0.2);
    border-radius: 4px;
    padding: 4px 12px;
    font-family: monospace;
    font-size: 11px;
    color: var(--accent);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    margin-bottom: 16px;
}

.logo-badge::before {
    content: '◉';
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}

.header-inner h1 {
    font-family: 'Quicksand', sans-serif;
    font-size: clamp(32px, 5vw, 56px);
    font-weight: 800;
    line-height: 1;
    letter-spacing: -0.02em;
    color: var(--text);
}

.header-inner h1 span {
    color: var(--accent);
}

.subtitle {
    margin-top: 12px;
    color: var(--muted);
    font-size: 15px;
    max-width: 480px;
    line-height: 1.6;
}

.header-stats {
    display: flex;
    gap: 32px;
    flex-shrink: 0;
}

.stat {
    text-align: right;
}

.stat-val {
    font-family: monospace;
    font-size: 22px;
    color: var(--accent);
    font-weight: 500;
}

.stat-lbl {
    font-size: 11px;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-top: 2px;
}

/* NAV TABS */
.nav-tabs {
    display: flex;
    gap: 4px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 4px;
    margin-bottom: 32px;
    overflow-x: auto;
    scrollbar-width: none;
    flex-wrap: wrap;
}

.nav-tab {
    flex: 1;
    min-width: 140px;
    padding: 10px 16px;
    border: none;
    border-radius: 7px;
    background: transparent;
    color: var(--muted);
    font-family: 'Quicksand', sans-serif;
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    white-space: nowrap;
    display: flex;
    align-items: center;
    gap: 8px;
    justify-content: center;
}

.nav-tab:hover {
    color: var(--text);
    background: rgba(0,0,0,0.06);
}

.nav-tab.active {
    background: var(--card);
    color: var(--accent);
    border: 1px solid rgba(0,0,0,0.3);
    box-shadow: 0 0 20px rgba(0,0,0,0.08);
}

.tab-icon { font-size: 16px; }

/* SECTIONS */
.section { display: none; }
.section.active { display: block; animation: fadeIn 0.3s ease; }

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

.section-header {
    margin-bottom: 28px;
}

.section-header h2 {
    font-family: 'Quicksand', sans-serif;
    font-size: 26px;
    font-weight: 700;
    color: var(--text);
}

.section-header p {
    color: var(--muted);
    font-size: 14px;
    margin-top: 6px;
    line-height: 1.6;
}

/* CALC GRID */
.calc-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

@media (max-width: 768px) {
    .calc-grid { grid-template-columns: 1fr; }
    .header-inner { flex-direction: column; }
    .header-stats { flex-direction: row; align-self: stretch; justify-content: space-between; }
}

.calc-card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 24px;
    transition: border-color 0.2s ease;
}

.calc-card:hover {
    border-color: rgba(0,0,0,0.4);
}

.calc-card.full-width {
    grid-column: 1 / -1;
}

.card-title {
    font-family: 'Quicksand', sans-serif;
    font-size: 15px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 4px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.card-title::before {
    content: '';
    width: 3px;
    height: 14px;
    background: var(--accent);
    border-radius: 2px;
    flex-shrink: 0;
}

.card-desc {
    font-size: 12px;
    color: var(--muted);
    margin-bottom: 20px;
    line-height: 1.5;
    padding-left: 11px;
}

/* FORMULA DISPLAY */
.formula-box {
    background: rgba(0,0,0,0.05);
    border: 1px solid rgba(0,0,0,0.12);
    border-radius: 8px;
    padding: 10px 14px;
    margin-bottom: 18px;
    font-family: monospace;
    font-size: 13px;
    color: #000000;
    text-align: center;
    letter-spacing: 0.02em;
}

/* INPUTS */
.input-group {
    margin-bottom: 14px;
}

.input-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

label {
    display: block;
    font-size: 11px;
    font-weight: 500;
    color: var(--label);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 6px;
}

.input-wrap {
    position: relative;
}

input[type="number"], input[type="date"], select {
    width: 100%;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 7px;
    padding: 10px 12px;
    color: var(--text);
    font-family: monospace;
    font-size: 14px;
    outline: none;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
    appearance: none;
}

input[type="number"]:focus, input[type="date"]:focus, select:focus {
    border-color: rgba(0,0,0,0.6);
    box-shadow: 0 0 0 3px rgba(0,0,0,0.08);
}

input[type="number"]::-webkit-inner-spin-button { opacity: 0.3; }

.unit-label {
    position: absolute;
    right: 10px;
    top: 50%;
    transform: translateY(-50%);
    font-family: monospace;
    font-size: 11px;
    color: var(--muted);
    pointer-events: none;
}

/* CALC BUTTON */
.calc-btn {
    width: 100%;
    margin-top: 16px;
    padding: 12px;
    background: #000000;
    border: 1px solid #000000;
    border-radius: 8px;
    color: #ffffff;
    font-family: 'Quicksand', sans-serif;
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    cursor: pointer;
    transition: all 0.2s ease;
}

.calc-btn:hover {
    background: #333333;
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
}

.calc-btn:active { transform: scale(0.98); }

/* RESULT */
.result-box {
    margin-top: 16px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 14px 16px;
    display: none;
}

.result-box.show { display: block; animation: fadeIn 0.2s ease; }

.result-label {
    font-size: 11px;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 6px;
}

.result-value {
    font-family: monospace;
    font-size: 24px;
    font-weight: 500;
    color: #000000;
}

.result-unit {
    font-size: 14px;
    color: var(--muted);
    margin-left: 4px;
}

.result-note {
    margin-top: 8px;
    font-size: 12px;
    color: var(--muted);
    line-height: 1.5;
    border-top: 1px solid var(--border);
    padding-top: 8px;
}

.result-warn { color: #555555; }
.result-ok { color: #000000; font-weight: 600; }
.result-err { color: #000000; font-weight: 600; text-decoration: underline; }

/* INFO BOX */
.info-box {
    background: rgba(0,0,0,0.04);
    border: 1px solid rgba(0,0,0,0.1);
    border-radius: 8px;
    padding: 12px 14px;
    margin-bottom: 18px;
    font-size: 12px;
    color: var(--label);
    line-height: 1.6;
}

/* Saugnapf visualizer */
.visualizer {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 16px;
    margin-top: 16px;
    display: flex;
    align-items: center;
    justify-content: space-around;
    flex-wrap: wrap;
    gap: 12px;
}

.vis-item { text-align: center; }

.vis-circle {
    border-radius: 50%;
    background: conic-gradient(var(--accent) 0deg, var(--border) 0deg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 8px;
    transition: all 0.5s ease;
}

.vis-inner {
    border-radius: 50%;
    background: var(--surface);
    display: flex;
    align-items: center;
    justify-content: center;
}

.vis-val {
    font-family: monospace;
    font-size: 11px;
    color: var(--accent);
    font-weight: 500;
}

.vis-lbl {
    font-size: 11px;
    color: var(--muted);
    margin-top: 4px;
}

/* REFERENCE TABLE */
.ref-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
    margin-top: 8px;
}

.ref-table th {
    text-align: left;
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--muted);
    padding: 8px 12px;
    border-bottom: 1px solid var(--border);
    font-weight: 500;
}

.ref-table td {
    padding: 9px 12px;
    border-bottom: 1px solid rgba(0,0,0,0.08);
    color: var(--label);
    font-family: monospace;
    font-size: 12px;
}

.ref-table tr:last-child td { border-bottom: none; }
.ref-table tr:hover td { background: rgba(0,0,0,0.03); }
.ref-table td:first-child { color: var(--text); font-family: 'Quicksand', sans-serif; }

/* DIVIDER */
.divider {
    height: 1px;
    background: var(--border);
    margin: 28px 0;
}

/* RANGE slider */
.slider-wrap {
    display: flex;
    align-items: center;
    gap: 10px;
}

input[type="range"] {
    flex: 1;
    -webkit-appearance: none;
    height: 3px;
    background: var(--border);
    border-radius: 3px;
    outline: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: #000000;
    cursor: pointer;
    box-shadow: 0 2px 6px rgba(0,0,0,0.3);
}

.slider-val {
    font-family: monospace;
    font-size: 13px;
    color: var(--accent);
    min-width: 42px;
    text-align: right;
}

/* PROGRESS BAR */
.progress-bar {
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    overflow: hidden;
    margin-top: 4px;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #333333, #000000);
    border-radius: 3px;
    transition: width 0.4s ease;
}

select option { background: var(--card); }

/* PWA Install-Banner */
.pwa-install-banner {
    display: none;
    align-items: center;
    gap: 12px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 12px 16px;
    margin-bottom: 20px;
    font-size: 0.875rem;
    color: var(--text);
}

.pwa-install-banner span {
    flex: 1;
}

.pwa-install-banner .pwa-install-btn {
    background: var(--accent);
    color: #ffffff;
    border: none;
    border-radius: 6px;
    padding: 7px 16px;
    font-size: 0.8rem;
    font-family: inherit;
    cursor: pointer;
    white-space: nowrap;
    transition: opacity 0.2s;
}

.pwa-install-banner .pwa-install-btn:hover {
    opacity: 0.8;
}

.pwa-install-banner .pwa-dismiss-btn {
    background: none;
    border: none;
    color: var(--muted);
    font-size: 1.1rem;
    cursor: pointer;
    padding: 0 4px;
    line-height: 1;
    font-family: inherit;
}

.pwa-install-banner .pwa-dismiss-btn:hover {
    color: var(--text);
}