/*--------------------------------------------------------------
# CSS Variables and Design Tokens
--------------------------------------------------------------*/
:root {
    /* Colors */
    --color-white: rgb(214, 220, 229);
    --color-white-transparent: rgba(214, 220, 229, 0.3);
    --color-background: rgb(15, 23, 42);
    --color-header-footer: rgb(8, 12, 21);
    --color-card-modal: rgb(30, 41, 59);
    
    /* Spacing */
    --spacing-xs: 0.3125rem;
    --spacing-sm: 0.625rem;
    --spacing-md: 1.25rem;
    --spacing-lg: 2.5rem;
    
    /* Borders */
    --border-radius-sm: 0.625rem;
    --border-radius-md: 0.9375rem;
    --border-width: 0.125rem;
    --border-width-lg: 0.3125rem;
    
    /* Animations */
    --transition-fast: 0.3s ease;
    --transition-medium: 0.75s ease;
    --transition-slow: 1.5s ease;
    
    /* Shadows */
    --shadow-sm: 0 0 1.25rem var(--color-white-transparent);
    --shadow-lg: 0 0 2.5rem var(--color-white);
}

/*--------------------------------------------------------------
# Base Elements
--------------------------------------------------------------*/
html {
    scroll-behavior: smooth !important;
}

body, html {
    margin: 0;
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: var(--color-white);
    background-color: var(--color-background);
}

main {
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

/*--------------------------------------------------------------
# Header & Footer
--------------------------------------------------------------*/
header, footer {
    left: 0;
    right: 0;
    z-index: 1000;
}

header { 
    position: fixed;
    top: 0; 
    background-color: var(--color-background);
}

footer { 
    bottom: 0; 
    background-image: linear-gradient(var(--color-background), var(--color-header-footer) 90%);
}

.fading-header,
.fading-footer {
    left: 0;
    right: 0;
    z-index: 1000;
    opacity: 0;
}

.fading-header.visible,
.fading-footer.visible {
    animation: fadeIn var(--transition-medium) forwards;
}

/*--------------------------------------------------------------
# Navigation
--------------------------------------------------------------*/
.custom-navbar {
    max-width: 80rem;
    margin: 0 auto;
    border-radius: 0 0 10px 10px;
    border-bottom: var(--border-width) solid var(--color-white);
    padding: 0;
}

.custom-navbar .container {
    padding: 0 5px 1px 5px;
    margin: 0;
}

.navbar-nav .nav-link {
    transition: transform var(--transition-fast), color var(--transition-fast);
}

.navbar-nav .nav-link:hover {
    transform: scale(1.1);
}

/*--------------------------------------------------------------
# Hero Section
--------------------------------------------------------------*/
.hero {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100vh;
    text-align: center;
    position: relative;
}

.welcome-container {
    text-align: center;
    opacity: 0;
    border: var(--border-width-lg) solid var(--color-white-transparent);
    position: relative;
    z-index: 2;
    border-radius: var(--border-radius-md);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
    max-width: 80%;
    margin: 0 auto;
    animation: welcomeFadeIn var(--transition-slow) forwards, 
               welcomeAnimateBorder var(--transition-slow) forwards, 
               welcomeAnimateBoxShadow var(--transition-slow) forwards;
}

.welcome-title {
    font-size: clamp(3rem, 5vw, 6rem);
    margin: 0;
    animation-duration: 1s;
}

.welcome-subtitle {
    font-size: clamp(1rem, 2vw, 2rem);
    margin: var(--spacing-md) 0;
    animation-duration: 1.2s;
}

/*--------------------------------------------------------------
# Arrow Animation
--------------------------------------------------------------*/
.arrow {
    opacity: 0;
    font-size: 1.5rem;
    animation: slideIn var(--transition-slow) forwards, 
               fadeIn var(--transition-slow) forwards;
    cursor: pointer;
    display: inline-block;
    padding: 0;
    margin: 0 -0.25rem;
    transition: color var(--transition-fast);
}

.center-animation {
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 4rem;
    height: 4rem;
    margin: 0 auto;
    position: relative;
    transition: transform var(--transition-fast), 
                color var(--transition-fast), 
                border-color var(--transition-fast);
    text-align: center;
}

.center-animation:hover {
    color: var(--color-white);
    transform: scale(1.1);
}

.center-animation::before,
.center-animation::after {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 100%;
    transform-origin: center;
    border-radius: var(--border-radius-sm);
    transition: border-color var(--transition-fast);
}

.center-animation::before {
    border-top: var(--border-width) solid var(--color-white-transparent);
    border-bottom: var(--border-width) solid var(--color-white-transparent);
    transform: scale3d(0, 1, 1);
    animation: scaleBefore 3s forwards;
    animation-delay: 1.5s;
}

.center-animation::after {
    border-left: var(--border-width) solid var(--color-white-transparent);
    border-right: var(--border-width) solid var(--color-white-transparent);
    transform: scale3d(1, 0, 1);
    animation: scaleAfter 3s forwards;
    animation-delay: 1.5s;
}

.center-animation:hover::before,
.center-animation:hover::after {
    border-color: var(--color-white);
}

/*--------------------------------------------------------------
# Content Containers
--------------------------------------------------------------*/
.greeting-container,
.about-container,
.imprint-container {
    max-width: 40rem; 
    margin: 0 auto;
    padding: var(--spacing-md);
    text-align: left;
    border-top: var(--border-width) solid var(--color-white);
}

.projects-container,
.cv-container {
    max-width: 80rem; 
    margin: 0 auto;
    padding: var(--spacing-md);
    text-align: left;
    border-top: var(--border-width) solid var(--color-white);
}

/*--------------------------------------------------------------
# Cards & Modals
--------------------------------------------------------------*/
.card-row {
    padding-top: var(--spacing-md);
}

.card {
    width: 18.75rem;
    cursor: pointer;
    margin-bottom: var(--spacing-md);
    border: var(--border-width) solid var(--color-white);
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
    overflow: hidden;
}

.card:hover {
    transform: scale(1.1);
    box-shadow: var(--shadow-lg);
}

.card-img-top {
    max-width: 18.75rem;
    width: 100%;
    height: auto;
    object-fit: cover;
    border-bottom: var(--border-width) solid var(--color-white);
}

.card-body {
    background-color: var(--color-card-modal);
    color: var(--color-white);
}

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

.modal-content {
    background-color: var(--color-card-modal);
    border: var(--border-width) solid var(--color-white);
}

/*--------------------------------------------------------------
# Buttons & Interactive Elements
--------------------------------------------------------------*/
.btn {
    color: var(--color-white) !important;
    border: var(--border-width) var(--color-white-transparent) solid !important;
    background-color: transparent !important;
    transition: transform var(--transition-fast), border-color var(--transition-fast) !important;
}

.btn:hover {
    border: var(--border-width) var(--color-white) solid !important;
    background-color: transparent !important;
    transform: scale(1.05) !important;
}

.btn:focus, 
.btn:active,
.btn:hover, 
.btn:focus, 
.btn:active, 
.btn:active:focus:not(:disabled):not(.disabled) {
    background-color: transparent !important;
    box-shadow: none !important;
    outline: 0 !important;
}

.btn-close {
    color: var(--color-white) !important;
}

.btn-close-custom {
    filter: invert(1) sepia(1) saturate(5) hue-rotate(175deg);
}

/*--------------------------------------------------------------
# CV & Profile Elements
--------------------------------------------------------------*/
.cv-iframe {
    width: 70%;
    height: 80vh;
    border: none;
}

#adrian-schoen-img {
    max-width: 20rem;
    width: 100% !important;
    border: 3px solid var(--color-white);
    box-shadow: inset 0 0 0 1px var(--color-white);
}

/*--------------------------------------------------------------
# Utility Classes
--------------------------------------------------------------*/
body::-webkit-scrollbar {
    width: 0;
    height: 0;
}

/*--------------------------------------------------------------
# Animations
--------------------------------------------------------------*/
@keyframes welcomeFadeIn {
    0% { opacity: 0; }
    100% { opacity: 1; }
}

@keyframes welcomeAnimateBorder {
    100% { border-color: var(--color-white); }
}

@keyframes welcomeAnimateBoxShadow {
    100% { box-shadow: var(--shadow-lg); }
}

@keyframes scaleBefore {
    0% { transform: scale3d(0, 1, 1); }
    100% { transform: scale3d(1, 1, 1); }
}

@keyframes scaleAfter {
    0% { transform: scale3d(1, 0, 1); }
    100% { transform: scale3d(1, 1, 1); }
}

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

@keyframes slideIn {
    from {
        transform: translateY(-6.25rem);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

/*--------------------------------------------------------------
# Media Queries
--------------------------------------------------------------*/
@media (min-width: 580px) {
    .arrow {
        font-size: 2rem;
    }
    .center-animation {
        width: 5rem;
        height: 5rem;
    }
}