:root {
    /* Basis Kleuren (kunnen ook in je hoofd stylesheet staan als ze gedeeld worden) */
    --primary-color: #00BBFF;
    --primary-color-darker: #00A3E0;
    --primary-color-rgb: 0, 187, 255;
    --white-color: #FFFFFF;
    --border-color-default: #ccc; /* Voor disabled state */
    --text-color-disabled: #777;

    /* Danger Kleuren */
    --danger-color-start: #ef4444;
    --danger-color-end: #dc2626;
    --danger-color-hover-start: #dc2626;
    --danger-color-hover-end: #b91c1c;
    --danger-shadow-color-rgba: 239, 68, 68;

    /* Lettertypen & Basis Afmetingen voor Buttons */
    --btn-font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --btn-font-weight: 600; /* font-weight-semibold */
    --btn-font-size: 1rem;
    --btn-padding: 16px 38px;
    --btn-border-radius: 8px; /* var(--border-radius-md) uit website */
    --btn-line-height: 1.5; /* Goede basis voor knoppen */

    --btn-max-width: 400px;
    --btn-margin: 10px 0;


    /* Transities */
    --transition-duration-fast: 0.2s;
    --transition-duration-medium: 0.3s;
    --transition-duration-bg-pos: 0.6s; /* Voor gradient transitie */
    --transition-timing-ease-out: ease-out;

    /* Primary Button Specifiek */
    --btn-primary-text-color: var(--white-color);
    --btn-primary-shadow: 0 4px 15px 0 rgba(var(--primary-color-rgb), 0.35);
    --btn-primary-bg-image: linear-gradient(to right, var(--primary-color) 0%, var(--primary-color-darker) 55%, var(--primary-color) 100%);
    --btn-primary-bg-size: 250% 100%;
    --btn-primary-bg-position: right bottom;
    
    --btn-primary-hover-bg-color: var(--primary-color-darker); /* Fallback */
    --btn-primary-hover-transform: translateY(-3px) scale(1.02);
    --btn-primary-hover-shadow: 0 7px 20px 0 rgba(var(--primary-color-rgb), 0.40);
    --btn-primary-hover-bg-position: left bottom;
    --btn-primary-active-transform: translateY(-1px) scale(0.98);

    /* Outline (Secondary) Button Specifiek */
    --btn-outline-text-color: var(--primary-color);
    --btn-outline-border-color: var(--primary-color);
    --btn-outline-border-width: 2px;
    --btn-outline-hover-bg-color: rgba(var(--primary-color-rgb), 0.08);
    --btn-outline-hover-text-color: var(--primary-color-darker);
    --btn-outline-hover-border-color: var(--primary-color-darker);
    --btn-outline-hover-transform: var(--btn-primary-hover-transform); /* Gelijk aan primary voor consistentie */
    --btn-outline-active-bg-color: rgba(var(--primary-color-rgb), 0.12);
    --btn-outline-active-transform: var(--btn-primary-active-transform); /* Gelijk aan primary */
}

/* Basis .btn stijl */
.btn {
    display: inline-block; /* of inline-flex voor align-items in de knop zelf */
    padding: var(--btn-padding);
    font-family: var(--btn-font-family);
    font-size: var(--btn-font-size);
    font-weight: var(--btn-font-weight);
    line-height: var(--btn-line-height);
    text-align: center;
    text-decoration: none;
    cursor: pointer;
    border: var(--btn-outline-border-width) solid transparent; /* Basis voor border, outline voegt kleur toe */
    border-radius: var(--btn-border-radius);
    
    transition-property: background-color, color, border-color, transform, box-shadow, background-position;
    transition-duration: var(--transition-duration-fast), var(--transition-duration-fast), var(--transition-duration-fast), var(--transition-duration-fast), var(--transition-duration-fast), var(--transition-duration-bg-pos);
    transition-timing-function: var(--transition-timing-ease-out);

    margin: var(--btn-margin);
    width: -webkit-fill-available;
    max-width: var(--btn-max-width);
    box-sizing: border-box;
}

/* Primary Button */
.btn-primary,
.convertBtn { /* .convertBtn is een alias */
    color: var(--btn-primary-text-color);
    background-image: var(--btn-primary-bg-image);
    background-size: var(--btn-primary-bg-size);
    background-position: var(--btn-primary-bg-position);
    box-shadow: var(--btn-primary-shadow);
    border-color: transparent; /* Zorgt ervoor dat de basis border niet interfereert */
}

.btn-primary:hover,
.convertBtn:hover {
    background-color: var(--btn-primary-hover-bg-color); /* Fallback */
    transform: var(--btn-primary-hover-transform);
    box-shadow: var(--btn-primary-hover-shadow);
    background-position: var(--btn-primary-hover-bg-position);
    color: var(--btn-primary-text-color); /* Behoud tekstkleur */
}

.btn-primary:active,
.convertBtn:active {
    transform: var(--btn-primary-active-transform);
    background-image: var(--btn-primary-bg-image); /* Behoud gradient bij active */
    background-position: var(--btn-primary-hover-bg-position); /* Of een andere positie voor active */
}

/* Outline (Secondary) Button */
.btn-outline {
    color: var(--btn-outline-text-color);
    background-color: transparent;
    background-image: none;
    border-color: var(--btn-outline-border-color);
    box-shadow: none;
}

.btn-outline:hover {
    color: var(--btn-outline-hover-text-color);
    background-color: var(--btn-outline-hover-bg-color);
    border-color: var(--btn-outline-hover-border-color);
    transform: var(--btn-outline-hover-transform);
    box-shadow: none;
}

.btn-outline:active {
    color: var(--btn-outline-hover-text-color);
    background-color: var(--btn-outline-active-bg-color);
    border-color: var(--btn-outline-hover-border-color);
    transform: var(--btn-outline-active-transform);
    box-shadow: none;
}

/* Danger Button */
.btn-danger {
    color: var(--btn-primary-text-color); /* Meestal witte tekst op rode achtergrond */
    background: linear-gradient(135deg, var(--danger-color-start) 0%, var(--danger-color-end) 100%);
    box-shadow: 0 4px 6px rgba(var(--danger-shadow-color-rgba), 0.2);
    border-color: transparent;
}

.btn-danger:hover {
    color: var(--btn-primary-text-color);
    background: linear-gradient(135deg, var(--danger-color-hover-start) 0%, var(--danger-color-hover-end) 100%);
    transform: translateY(-2px); /* Behoudt de unieke hover van danger */
    box-shadow: 0 8px 25px rgba(var(--danger-shadow-color-rgba), 0.3);
}

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

/* Focus State (voor alle .btn types) */
.btn:focus,
button.btn:focus { /* button.btn voor specificiteit als je <button class="btn"> gebruikt */
    outline: none; /* Verwijder standaard browser outline */
    box-shadow: 0 0 0 3px rgba(var(--primary-color-rgb), 0.4), var(--btn-primary-shadow); /* Combineer focus met bestaande shadow */
}
.btn-outline:focus {
    box-shadow: 0 0 0 3px rgba(var(--primary-color-rgb), 0.4); /* Outline heeft geen initiële shadow */
}
.btn-danger:focus {
     box-shadow: 0 0 0 3px rgba(var(--danger-shadow-color-rgba), 0.4), 0 4px 6px rgba(var(--danger-shadow-color-rgba), 0.2);
}


/* Disabled State (voor alle .btn types) */
.btn:disabled,
button.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important; /* Override hover/active transforms */
    box-shadow: none !important;
    background-image: none !important;
    background-color: var(--border-color-default) !important;
    color: var(--text-color-disabled) !important;
    border-color: var(--border-color-default) !important;
}