:root {
    --color-black: #31363b;
    --color-bright-black: #6b757f;
    --color-alt-black: #232629;
    --color-faint-black: #3b4045;
    /* Red */
    --color-red: #c6344a;
    --color-bright-red: #e974a3;
    --color-alt-red: #de565d;
    --color-faint-red: #fea3c4;
    /* Green */
    --color-green: #00c944;
    --color-bright-green: #2cde85;
    --color-alt-green: #71a144;
    --color-faint-green: #b4de69;
    /* Yellow */
    --color-yellow: #f15a22;
    --color-bright-yellow: #ffac33;
    --color-alt-yellow: #ffcc4d;
    --color-faint-yellow: #ffe794;
    /* Blue */
    --color-blue: #1793d1;
    --color-bright-blue: #3daee9;
    --color-alt-blue: #4c7de3;
    --color-faint-blue: #37c7ef;
    /* Magenta */
    --color-magenta: #a460c7;
    --color-bright-magenta: #a672fb;
    --color-alt-magenta: #a05b7d;
    --color-faint-magenta: #8e6ae8;
    /* Cyan */
    --color-cyan: #04bac5;
    --color-bright-cyan: #99d9e8;
    --color-alt-cyan: #64e9db;
    --color-faint-cyan: #76a1ac;
    /* White */
    --color-white: #bdc3c7;
    --color-bright-white: #eff0f1;
    --color-alt-white: #a7b1ba;
    --color-faint-white: #fcfcfc;

    /* Define Speicial Colors */
    --color-main: var(--color-bright-blue);
    --color-accent: var(--color-bright-red);
    --color-background: var(--color-alt-black);
    --color-foreground: var(--color-bright-white);
    --color-base: var(--color-black);
    --color-base-alt: var(--color-faint-black);
    --color-main-hover: var(--color-faint-blue);

    /* border-radius */
    --radius-size: 4px;

    /* transition */
    --transition-duration: 0.2s;
    transition-behavior: allow-discrete;
}

@media (prefers-color-scheme: dark) {
    :root {
        color-scheme: dark;
        --color-background: var(--color-alt-black);
        --color-foreground: var(--color-bright-white);
        --color-foreground-alt: var(--color-white);
        --color-base: var(--color-black);
        --color-base-alt: var(--color-faint-black);
        --color-main-hover: var(--color-faint-blue);
    }
}

@media (prefers-color-scheme: light) {
    :root {
        color-scheme: light;
        --color-background: var(--color-faint-white);
        --color-foreground: var(--color-black);
        --color-foreground-alt: var(--color-alt-black);
        --color-base: var(--color-bright-white);
        --color-base-alt: var(--color-white);
        --color-main-hover: var(--color-blue);
    }
}

@media (prefers-reduced-motion: reduce) {
    :root {
        --transition-duration: none;
    }
}

/* - - - - reset CSS - - - - */
*,
*::before,
*::after {
    box-sizing: border-box;
}

* {
    margin: 0;
}

body {
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

img,
picture,
video,
canvas,
svg {
    display: block;
    max-width: 100%;
}

/* - - - - */

/* css utils */
.round {
    border-radius: var(--radius-size);
}

.margin-l-1rem {
    margin-left: 1rem;
}

.hide {
    display: none !important;
}

/* common */
body {
    flex-direction: column;
    color: var(--color-foreground);
    background-color: var(--color-background);
    overflow-wrap: anywhere;
    scroll-behavior: smooth;
}

a {
    color: var(--color-main);
    text-decoration: unset;
    transition: all var(--transition-duration);

    &:hover,
    &:focus-visible {
        color: var(--color-main-hover);
        text-decoration: underline;
        transition: all var(--transition-duration);
    }
}

details {
    &::details-content {
        display: grid;
        transition-duration: var(--transition-duration);
        transition-property: content-visibility, grid-template;
        transition-behavior: allow-discrete;
    
        /* closed */
        grid-template-rows: 0fr;
    }
    &[open]::details-content {
        grid-template-rows: 1fr;
}
}

/* components */
.big-image {
    width: 100vw;
    height: 100vh;
    /* background-color: var(--color-base); */
    /* https://developer.mozilla.org/ja/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element */
    display: flex;
    align-items: center;
    justify-content: center;
}

.profile-card {
    display: flex;
    background-color: var(--color-base);
    padding: 2rem;
    gap: 2rem;
    align-items: center;
}

@media (orientation: landscape) {
    .profile-card {
        flex-direction: row;
    }
}

@media (orientation: portrait) {
    .profile-card {
        flex-direction: column;
        text-align: center;
    }

    .profile-text {
        width: 25rem;
    }
}

.profile-picture {
    width: 25rem;
    height: 25rem;
}

.profile-text {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    min-width: 25rem;
    overflow-wrap: break-word;

    & h1 {
        font-size: 5rem;
    }
    & .horizontal-line {
        border-bottom: 1px dashed var(--color-base-alt);
    }
    & a {
        font-size: 3rem;
    }
}

.home {
    min-height: 100vh;
}

header {
    top: 0;
    height: 4rem;
    display: flex;
    gap: 1rem;
    padding: 1rem;
    font-size: 1.25rem;
    font-weight: bold;
    position: sticky;
    align-items: center;

    background-color: var(--color-base);

    & .header-picture {
        height: 2rem;
    }
}

section {
    margin: 1rem auto;
    max-width: 80%;
    padding: 1rem;
    border: 1px solid var(--color-base);

    & h2 {
        font-size: 2rem;
        padding: 0 0 1rem 0.5rem;
    }
}


.link-section {
    display: flex;
    flex-direction: column;
    justify-content: center;
    margin: 1rem;
}

.link-group-title {
    display: flex;
    justify-content: space-between;
    padding: 1rem;
    margin-top: 1rem;
    font-size: 1.5rem;
    cursor: pointer;
    overflow: hidden;
    border: 1px solid var(--color-base);
    border-radius: var(--radius-size);
    background-color: var(--color-base);
    list-style: none;
    transition: all var(--transition-duration);
    &:hover, &:focus-visible {
        background-color: var(--color-base-alt);
        transition: all var(--transition-duration);
    }
    &::after {
        content: "+";
        font-family: monospace;
        color: var(--color-foreground-alt);
    }
}

details[open] .link-group-title {
    margin-bottom: 1rem;
    background-color: transparent;
    transition: all var(--transition-duration);
    &:hover, &:focus-visible {
        background-color: var(--color-base-alt);
        transition: all var(--transition-duration);
    }
    &::after {
        content: "-";
        font-family: monospace;
        color: var(--color-foreground-alt);
    }
}

.link-button-group {
    gap: 1rem;
    display: grid;
    overflow: hidden;
    /* https://developer.mozilla.org/ja/docs/Web/CSS/Guides/Grid_layout/Relationship_with_other_layout_methods */
    grid-template-columns: repeat(auto-fit, minmax(clamp(10vw, 20rem, 40vw), 1fr));
}

.button {
    padding: 1rem;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 1rem;

    border-radius: var(--radius-size);
    color: var(--color-foreground);
    background-color: var(--color-base);
    transition: all var(--transition-duration);

    &:hover,
    &:focus-visible {
        color: currentColor;
        background-color: var(--color-main);
        transition: all var(--transition-duration);
    }

    & .button-picture {
        width: 2rem;
        height: 2rem;
        font-size: xx-small;
        overflow: auto;
    }
    & .button-title {
        font-size: 1.25rem;
    }
    & .button-detail {
        font-size: 0.75rem;
        padding-top: 0.25em;
        margin-left: auto;
        color: var(--color-foreground-alt);
        font-family: monospace;
    }
}