/* ============================================================
    CSS CUSTOM PROPERTIES (Design-Token-System)
    Alle Farben, Abstände und Typografie zentral definiert.
    Änderungen hier wirken sich global aus.
============================================================ */
:root {
    --c-bg:         #F4F6FA;
    --c-surface:    #FFFFFF;
    --c-surface2:   #F0F3F9;
    --c-border:     #DDE3EE;
    --c-accent:     #3B6FE8;
    --c-accent-lt:  #EBF0FD;
    --c-accent2:    #22C5A0;
    --c-accent2-lt: #E6FAF6;
    --c-warn:       #F59E0B;
    --c-warn-lt:    #FEF3C7;
    --c-text:       #1A1F36;
    --c-text2:      #5A6285;
    --c-text3:      #9BA3BF;
    --c-shadow:     0 2px 12px rgba(59,111,232,.08), 0 1px 3px rgba(0,0,0,.05);
    --c-shadow-lg:  0 8px 32px rgba(59,111,232,.12), 0 2px 8px rgba(0,0,0,.07);
    --radius:       14px;
    --radius-sm:    8px;
    --radius-xs:    5px;
    --font:         'DM Sans', sans-serif;
    --font-mono:    'DM Mono', monospace;
    --trans:        all .2s ease;
}

/* ============================================================
    RESET & BASIS-STILE
    Normalisiert Browser-Unterschiede; Box-Sizing global.
============================================================ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
    font-family: var(--font);
    background: var(--c-bg);
    color: var(--c-text);
    min-height: 100vh;
    padding: 0 0 60px;
    line-height: 1.6;
}

/* ============================================================
    HEADER — kompakte Titelzeile
    Schlanke Leiste im gleichen Stil wie die Karten-Header.
    Kein separater Hero-Block mehr — fügt sich nahtlos ein.
============================================================ */
.topbar {
    background: var(--c-surface);
    border-bottom: 1px solid var(--c-border);
    padding: 0 24px;
}
.topbar-inner {
    max-width: 1080px;
    margin: 0 auto;
    height: 56px;
    display: flex;
    align-items: center;
    gap: 10px;
}
.topbar-icon {
    width: 30px; height: 30px;
    background: var(--c-accent-lt);
    border-radius: 7px;
    display: flex; align-items: center; justify-content: center;
    font-size: 15px;
    flex-shrink: 0;
}
.topbar h1 {
    font-size: .95rem;
    font-weight: 600;
    letter-spacing: -.01em;
    color: var(--c-text);
}
.topbar-sep {
    width: 1px; height: 18px;
    background: var(--c-border);
    margin: 0 2px;
}
.topbar-sub {
    font-size: .82rem;
    color: var(--c-text3);
    font-weight: 400;
}

/* ============================================================
    HAUPT-LAYOUT
    Zweispaltiger Grid auf Desktop; einspaltiger Stack auf Mobil.
============================================================ */
.container {
    max-width: 1080px;
    margin: 0 auto;
    padding: 32px 20px 0;
}
.layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    align-items: start;
}
@media (max-width: 760px) {
    .layout { grid-template-columns: 1fr; }
}

/* ============================================================
    KARTEN (Cards)
    Einheitliche Oberfläche für alle Eingabe- und Ausgabegruppen.
============================================================ */
.card {
    background: var(--c-surface);
    border: 1px solid var(--c-border);
    border-radius: var(--radius);
    box-shadow: var(--c-shadow);
    overflow: hidden;
}
.card-header {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 18px 20px 14px;
    border-bottom: 1px solid var(--c-border);
}
.card-header-icon {
    width: 32px; height: 32px;
    border-radius: var(--radius-xs);
    display: flex; align-items: center; justify-content: center;
    font-size: 16px;
    flex-shrink: 0;
}
.card-header h2 {
    font-size: .9rem;
    font-weight: 600;
    letter-spacing: .01em;
    color: var(--c-text);
}
.card-header span.sub {
    font-size: .78rem;
    color: var(--c-text3);
    font-weight: 400;
    margin-left: 4px;
}
.card-body { padding: 20px; }

/* ============================================================
    FORMULAR-ELEMENTE
    Beschriftungen, Eingabefelder, Slider und Schnellauswahl-Chips.
============================================================ */
.field { margin-bottom: 20px; }
.field:last-child { margin-bottom: 0; }

label.field-label {
    display: flex;
    align-items: baseline;
    gap: 6px;
    font-size: .82rem;
    font-weight: 600;
    color: var(--c-text2);
    text-transform: uppercase;
    letter-spacing: .06em;
    margin-bottom: 8px;
}
label.field-label .unit {
    font-size: .75rem;
    color: var(--c-text3);
    font-weight: 400;
    text-transform: none;
    letter-spacing: 0;
}

/* Eingabefeld mit Einheit-Badge */
.input-wrap {
    position: relative;
    display: flex;
    align-items: center;
}
.input-wrap input[type="number"] {
    width: 100%;
    padding: 10px 60px 10px 14px;
    border: 1.5px solid var(--c-border);
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: .95rem;
    color: var(--c-text);
    background: var(--c-surface2);
    outline: none;
    transition: var(--trans);
    appearance: textfield;
}
.input-wrap input[type="number"]::-webkit-inner-spin-button,
.input-wrap input[type="number"]::-webkit-outer-spin-button { -webkit-appearance: none; }
.input-wrap input[type="number"]:focus {
    border-color: var(--c-accent);
    background: #fff;
    box-shadow: 0 0 0 3px rgba(59,111,232,.12);
}
.input-unit {
    position: absolute; right: 10px;
    font-size: .75rem;
    color: var(--c-text3);
    font-weight: 500;
    pointer-events: none;
}

/* Slider */
.slider-wrap { display: flex; align-items: center; gap: 10px; margin-top: 8px; }
input[type="range"] {
    -webkit-appearance: none;
    flex: 1;
    height: 4px;
    border-radius: 99px;
    background: var(--c-border);
    outline: none;
    cursor: pointer;
    transition: var(--trans);
}
input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 18px; height: 18px;
    border-radius: 50%;
    background: var(--c-accent);
    border: 2px solid #fff;
    box-shadow: 0 1px 4px rgba(59,111,232,.35);
    transition: var(--trans);
}
input[type="range"]:hover::-webkit-slider-thumb { transform: scale(1.15); }
.slider-val {
    font-size: .82rem;
    font-family: var(--font-mono);
    color: var(--c-accent);
    font-weight: 500;
    min-width: 28px;
    text-align: right;
}

/* Schnellauswahl-Chips (Preset-Buttons) */
.chips {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-top: 8px;
}
.chip {
    padding: 4px 11px;
    border-radius: 99px;
    border: 1.5px solid var(--c-border);
    font-size: .78rem;
    font-weight: 500;
    color: var(--c-text2);
    background: var(--c-surface);
    cursor: pointer;
    transition: var(--trans);
    white-space: nowrap;
}
.chip:hover {
    border-color: var(--c-accent);
    color: var(--c-accent);
    background: var(--c-accent-lt);
}
.chip.active {
    border-color: var(--c-accent);
    background: var(--c-accent);
    color: #fff;
}

/* ============================================================
    ERGEBNIS-KARTE (rechte Spalte)
    Zeigt die berechneten Werte übersichtlich an.
============================================================ */
.result-card { top: 20px; }
@media (max-width: 760px) { .result-card { position: static; } }

/* Haupt-Ergebnis-Anzeige */
.result-main {
    text-align: center;
    padding: 24px 20px 18px;
    border-bottom: 1px solid var(--c-border);
}
.result-label {
    font-size: .78rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: .08em;
    color: var(--c-text3);
    margin-bottom: 6px;
}
.result-value {
    font-size: clamp(2rem, 6vw, 2.8rem);
    font-weight: 600;
    color: var(--c-accent);
    font-family: var(--font-mono);
    letter-spacing: -.03em;
    transition: var(--trans);
    line-height: 1.1;
}
.result-unit {
    font-size: 1rem;
    color: var(--c-text2);
    margin-top: 2px;
}

/* Dezimal / Binär Umschalter */
.mode-toggle {
    display: flex;
    gap: 0;
    background: var(--c-surface2);
    border: 1px solid var(--c-border);
    border-radius: var(--radius-sm);
    padding: 3px;
    margin: 14px auto 0;
    width: fit-content;
}
.mode-btn {
    padding: 5px 16px;
    border-radius: 5px;
    font-size: .8rem;
    font-weight: 600;
    color: var(--c-text2);
    cursor: pointer;
    transition: var(--trans);
    border: none;
    background: transparent;
}
.mode-btn.active {
    background: var(--c-surface);
    color: var(--c-accent);
    box-shadow: 0 1px 4px rgba(0,0,0,.1);
}

/* Einzelne Ergebniszeilen (alle Einheiten) */
.result-rows { padding: 16px 20px; border-bottom: 1px solid var(--c-border); }
.result-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 0;
    border-bottom: 1px solid var(--c-surface2);
    gap: 12px;
}
.result-row:last-child { border-bottom: none; }
.rr-left {
    display: flex;
    align-items: center;
    gap: 8px;
    min-width: 0;
}
.rr-dot {
    width: 8px; height: 8px;
    border-radius: 50%;
    flex-shrink: 0;
}
.rr-name {
    font-size: .83rem;
    color: var(--c-text2);
    white-space: nowrap;
}
.rr-val {
    font-family: var(--font-mono);
    font-size: .85rem;
    font-weight: 500;
    color: var(--c-text);
    text-align: right;
}

/* Binär-Hinweisfeld */
.binary-box {
    margin: 16px 20px;
    background: var(--c-warn-lt);
    border: 1px solid rgba(245,158,11,.25);
    border-radius: var(--radius-sm);
    padding: 14px 16px;
}
.binary-box-header {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: .78rem;
    font-weight: 600;
    color: var(--c-warn);
    text-transform: uppercase;
    letter-spacing: .06em;
    margin-bottom: 8px;
}
.binary-rows .result-row { border-bottom: 1px solid rgba(245,158,11,.12); }
.binary-rows .result-row:last-child { border-bottom: none; }
.binary-rows .rr-name { color: #92621a; }
.binary-rows .rr-val { color: #6b4811; }
.binary-note {
    font-size: .73rem;
    color: #a07020;
    margin-top: 10px;
    line-height: 1.5;
}

/* ============================================================
    RECHENWEG-PANEL (Live-Formel-Anzeige)
    Zeigt Schritt für Schritt, wie das Ergebnis entstand.
============================================================ */
.formula-card { margin-top: 24px; }
.formula-steps { padding: 20px; }
.formula-step {
    display: flex;
    gap: 14px;
    margin-bottom: 16px;
    align-items: flex-start;
}
.formula-step:last-child { margin-bottom: 0; }
.step-num {
    width: 24px; height: 24px;
    border-radius: 50%;
    background: var(--c-accent);
    color: #fff;
    font-size: .72rem;
    font-weight: 700;
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0;
    margin-top: 2px;
}
.step-content { flex: 1; min-width: 0; }
.step-title {
    font-size: .82rem;
    font-weight: 600;
    color: var(--c-text);
    margin-bottom: 3px;
}
.step-expr {
    font-family: var(--font-mono);
    font-size: .8rem;
    color: var(--c-text2);
    background: var(--c-surface2);
    border: 1px solid var(--c-border);
    border-radius: var(--radius-xs);
    padding: 6px 10px;
    margin: 4px 0;
    word-break: break-all;
}
.step-result {
    font-family: var(--font-mono);
    font-size: .82rem;
    color: var(--c-accent);
    font-weight: 600;
}
.step-desc {
    font-size: .78rem;
    color: var(--c-text3);
    margin-top: 2px;
    line-height: 1.4;
}

/* Trennlinie zwischen Schritten */
.step-connector {
    width: 1px;
    height: 14px;
    background: var(--c-border);
    margin: 0 0 0 12px;
}

/* ============================================================
    VERGLEICHS-LEISTE
    Visualisiert wie viele typische Songs / Stunden passen würden.
============================================================ */
.compare-card { margin-top: 24px; }
.compare-items {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 10px;
    padding: 16px 20px;
}
.compare-item {
    background: var(--c-surface2);
    border: 1px solid var(--c-border);
    border-radius: var(--radius-sm);
    padding: 12px 14px;
    text-align: center;
}
.ci-icon { font-size: 1.4rem; margin-bottom: 4px; }
.ci-val {
    font-size: 1.1rem;
    font-weight: 600;
    font-family: var(--font-mono);
    color: var(--c-accent2);
    line-height: 1.2;
}
.ci-desc {
    font-size: .72rem;
    color: var(--c-text2);
    margin-top: 3px;
    line-height: 1.3;
}

/* ============================================================
    FLASH-ANIMATION (bei Wertänderung)
    Gibt dem Nutzer visuelles Feedback in Echtzeit.
============================================================ */
@keyframes flash {
    0%   { background: rgba(59,111,232,.12); }
    100% { background: transparent; }
}
.flash { animation: flash .4s ease; border-radius: 4px; }

/* ============================================================
    MODAL — Popup für den Rechenweg
    Überlagert den gesamten Inhalt mit einem Overlay.
    Öffnet sich mit sanfter Einblend- und Skalierungsanimation.
============================================================ */

/* Schaltfläche „Rechenweg zeigen" in der Ergebniskarte */
.btn-rechenweg {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 7px;
    width: calc(100% - 40px);
    margin: 0 20px 20px;
    padding: 10px 16px;
    border: 1.5px solid var(--c-accent);
    border-radius: var(--radius-sm);
    background: var(--c-accent-lt);
    color: var(--c-accent);
    font-family: var(--font);
    font-size: .85rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--trans);
}
.btn-rechenweg:hover {
    background: var(--c-accent);
    color: #fff;
}
.btn-rechenweg svg {
    flex-shrink: 0;
    transition: var(--trans);
}

/* Dunkles Overlay hinter dem Modal */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(15, 20, 40, 0.45);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    opacity: 0;
    pointer-events: none;
    transition: opacity .25s ease;
}
/* Sichtbarer Zustand: Klasse .open per JS gesetzt */
.modal-overlay.open {
    opacity: 1;
    pointer-events: all;
}

/* Modal-Fenster selbst */
.modal {
    background: var(--c-surface);
    border: 1px solid var(--c-border);
    border-radius: var(--radius);
    box-shadow: var(--c-shadow-lg);
    width: 100%;
    max-width: 660px;
    max-height: 85vh;
    display: flex;
    flex-direction: column;
    transform: scale(.96) translateY(12px);
    transition: transform .25s ease;
    overflow: hidden;
}
.modal-overlay.open .modal {
    transform: scale(1) translateY(0);
}

/* Modal-Kopfzeile mit Titel und Schließen-Button */
.modal-head {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 16px 20px;
    border-bottom: 1px solid var(--c-border);
    flex-shrink: 0;
}
.modal-head h3 {
    font-size: .92rem;
    font-weight: 600;
    color: var(--c-text);
    flex: 1;
}
.modal-head .sub {
    font-size: .78rem;
    color: var(--c-text3);
    font-weight: 400;
    margin-left: 4px;
}
.modal-close {
    width: 30px; height: 30px;
    border-radius: 50%;
    border: none;
    background: var(--c-surface2);
    color: var(--c-text2);
    font-size: 1rem;
    cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    transition: var(--trans);
    flex-shrink: 0;
}
.modal-close:hover {
    background: var(--c-border);
    color: var(--c-text);
}

/* Scrollbarer Inhaltsbereich des Modals */
.modal-body {
    overflow-y: auto;
    padding: 20px;
    flex: 1;
}
/* Dezente Scrollbar */
.modal-body::-webkit-scrollbar { width: 5px; }
.modal-body::-webkit-scrollbar-track { background: transparent; }
.modal-body::-webkit-scrollbar-thumb {
    background: var(--c-border);
    border-radius: 99px;
}

/* ============================================================
    FOOTER
============================================================ */
footer {
    text-align: center;
    margin-top: 40px;
    font-size: .75rem;
    color: var(--c-text3);
}

/* ============================================================
    HILFREICH: Tooltip
============================================================ */
[data-tip] { position: relative; cursor: help; }
[data-tip]::after {
    content: attr(data-tip);
    position: absolute;
    bottom: calc(100% + 6px);
    left: 50%; transform: translateX(-50%);
    background: var(--c-text);
    color: #fff;
    font-size: .72rem;
    padding: 5px 10px;
    border-radius: var(--radius-xs);
    white-space: nowrap;
    pointer-events: none;
    opacity: 0;
    transition: opacity .15s;
    z-index: 10;
}
[data-tip]:hover::after { opacity: 1; }