/* ============================================================
   WS05 – Responsive Design
   style.css — Mobile-first unified stylesheet
   ============================================================ */

/* ── 1. RESET & BASE ─────────────────────────────────────── */

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

body {
    margin: 0;
    padding: 0;
    background-color: var(--color-bg);
    font-family: Georgia, serif;
    color: #2c3e50;
}

/* ── 2. CSS CUSTOM PROPERTIES (VARIABLES) ────────────────── */
/* CSS variables let us define our colour palette once and   */
/* reuse it everywhere. Change a value here and it updates  */
/* throughout the entire stylesheet.                         */

:root {
    --color-primary:   steelblue;          /* #4682b4 */
    --color-dark:      #1a3a5c;
    --color-mid:       #2f5f89;
    --color-light-bg:  #e8f4fd;
    --color-bg:        #f0f4f8;
    --color-gold:      goldenrod;
    --color-text:      #2c3e50;
    --color-white:     #ffffff;

    --radius-sm:  4px;
    --radius-md:  8px;
    --radius-lg:  10px;

    --shadow-sm:  3px 3px 10px rgba(0, 0, 0, 0.08);
    --shadow-md:  4px 4px 12px rgba(0, 0, 0, 0.2);
    --shadow-lg:  8px 8px 20px rgba(0, 0, 0, 0.4);
    --shadow-hdr: 0 8px 18px rgba(0, 0, 0, 0.16);
}

/* ── 3. RESPONSIVE TYPOGRAPHY ────────────────────────────── */
/* clamp(min, preferred, max) produces fluid font sizes that */
/* scale with viewport width without needing media queries.  */

h1 {
    font-size: clamp(1.2rem, 4vw, 1.7rem);
    margin: 0;
    color: var(--color-white);
    line-height: 1.2;
}

h2 {
    font-size: clamp(1rem, 3vw, 1.3rem);
    color: var(--color-dark);
    margin-top: 0;
    margin-bottom: 12px;
}

h3 {
    font-size: clamp(0.9rem, 2.5vw, 1.1rem);
    color: var(--color-dark);
    margin-top: 16px;
    margin-bottom: 6px;
}

p {
    color: var(--color-text);
    font-size: 1.05rem;
    line-height: 1.7;
    padding: 12px 16px;
    background: var(--color-white);
    border-left: 4px solid var(--color-primary);
    border-radius: var(--radius-sm);
    margin-bottom: 16px;
}

p::first-letter {
    /* Drop-cap effect – ported from WS03 */
    font-size: 2rem;
    font-weight: bold;
    color: var(--color-primary);
    float: left;
    line-height: 1;
    margin-right: 4px;
}

/* h2 decorations – ported from WS03 */
h2::before {
    content: "▸ ";
    color: var(--color-primary);
}

h2::after {
    content: "";
    display: block;
    width: 40px;
    height: 3px;
    background-color: var(--color-primary);
    margin-top: 4px;
    border-radius: 2px;
}

/* ── 4. PAGE WRAPPER ─────────────────────────────────────── */
/* Constrain max-width and centre on large screens.          */

.page-wrapper {
    width: 100%;
    padding-left: 16px;
    padding-right: 16px;
    margin-left: auto;
    margin-right: auto;
}

/* ── 5. SITE HEADER ──────────────────────────────────────── */
/* Gradient banner with responsive typography via clamp().   */
/* min-height: 30vh keeps the header proportional to the     */
/* viewport height — a viewport-unit technique.              */

.site-header {
    padding: 16px 16px 0;
}

.site-header__content {
    background: linear-gradient(120deg, var(--color-dark) 0%, var(--color-mid) 65%, var(--color-primary) 100%);
    color: var(--color-white);
    padding: 18px 20px 20px;
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
    box-shadow: var(--shadow-hdr);
    min-height: 30vh;                   /* viewport-unit: proportional height */
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    animation: slideInDown 0.8s ease-out forwards;
}

.site-header__kicker {
    display: inline-block;
    font-size: 0.75rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: #cfe4f6;
    margin-bottom: 6px;
}

.site-header__subtitle {
    margin-top: 8px;
    font-size: clamp(0.85rem, 2vw, 0.98rem);
    color: #e6f1fa;
}

/* ── 6. RESPONSIVE NAVIGATION ───────────────────────────── */
/* CSS-only hamburger menu using the checkbox hack:          */
/*   - #nav-toggle (checkbox) is hidden visually             */
/*   - .nav-toggle-label (label) acts as the ☰ button        */
/*   - .nav-links is hidden until checkbox is checked        */
/* On desktop the checkbox/label are hidden and links are    */
/* always visible in a flex row.                             */

nav {
    background-color: var(--color-dark);
    padding: 0 16px;
    border-radius: 0 0 var(--radius-md) var(--radius-md);
    margin-bottom: 24px;
    position: relative;
}

/* Hide the actual checkbox */
.nav-toggle {
    display: none;
}

/* Hamburger icon label — visible on mobile */
.nav-toggle-label {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 0;
    color: var(--color-white);
    cursor: pointer;
    user-select: none;
    font-size: 0.95rem;
    font-weight: bold;
    letter-spacing: 0.04em;
}

/* Three-bar hamburger icon using ::after */
.nav-toggle-label::after {
    content: "☰";
    font-size: 1.4rem;
    line-height: 1;
}

/* Nav links: hidden by default on mobile, stacked vertically */
.nav-links {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding-bottom: 12px;
}

/* Show nav links when checkbox is checked (hamburger toggled) */
.nav-toggle:checked ~ .nav-links {
    display: flex;
}

.nav-links a {
    color: var(--color-white);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: bold;
    letter-spacing: 0.04em;
    padding: 8px 10px;
    border-radius: var(--radius-sm);
    transition: background-color 0.2s ease;
}

.nav-links a:hover {
    background-color: var(--color-primary);
}

.nav-links a.active {
    background-color: var(--color-primary);
    pointer-events: none;
}

/* ── 7. LAYOUT GRID ──────────────────────────────────────── */
/* Mobile-first: single column (block layout).               */
/* The sidebar is hidden below tablet breakpoint.            */

.layout-grid {
    display: block;
    margin-bottom: 32px;
}

/* ── 8. ASIDE / SIDEBAR ──────────────────────────────────── */
/* Hidden on mobile; shown above main on tablet;             */
/* sticky sidebar on desktop.                                */

aside {
    display: none;              /* hidden on mobile */
    background-color: var(--color-white);
    border: 2px solid var(--color-primary);
    border-radius: var(--radius-lg);
    padding: 20px 18px;
    box-shadow: var(--shadow-sm);
    margin-bottom: 24px;
}

aside h2::before,
aside h2::after {
    /* Remove decorators inside sidebar headings */
    display: none;
}

aside h3 {
    color: var(--color-dark);
    margin-top: 16px;
    margin-bottom: 6px;
}

aside code {
    background-color: var(--color-light-bg);
    color: var(--color-dark);
    font-family: monospace;
    font-size: 0.9rem;
    padding: 1px 5px;
    border-radius: 3px;
    border: 1px solid #b8d8f0;
}

aside a {
    display: inline-block;
    color: var(--color-primary);
    font-weight: bold;
    font-size: 0.9rem;
    text-decoration: none;
    margin-top: 4px;
    transition: color 0.2s ease;
}

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

/* Override paragraph styles inside aside */
aside p {
    background: none;
    border: none;
    padding: 0;
    font-size: 0.9rem;
    line-height: 1.5;
    margin-bottom: 8px;
}

aside p::first-letter {
    /* Reset drop-cap in sidebar */
    font-size: inherit;
    font-weight: inherit;
    color: inherit;
    float: none;
    margin-right: 0;
}

/* ── 9. MAIN CONTENT ─────────────────────────────────────── */

main section {
    margin-bottom: 32px;
}

/* ── 10. RESPONSIVE IMAGE GALLERY ───────────────────────── */
/* repeat(auto-fit, minmax(250px, 1fr)) automatically        */
/* reflows columns based on available space — no media       */
/* queries needed for the column count itself.               */

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 16px;
    margin-top: 16px;
}

.gallery-item {
    background: var(--color-white);
    border-radius: var(--radius-md);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: box-shadow 0.3s ease;
}

.gallery-item:hover {
    box-shadow: var(--shadow-lg);
}

/* Responsive images: fluid by default */
img {
    width: 100%;
    max-width: 100%;
    height: auto;
    display: block;
    filter: grayscale(100%) brightness(80%);  /* WS03 filter effect */
    transition: all 0.5s ease-in-out;
    border-radius: var(--radius-md);
}

img:hover {
    filter: none;
    transform: scale(1.04);
    box-shadow: var(--shadow-lg);
}

.gallery-item img {
    border-radius: 0;
    transform: none;
}

.gallery-item img:hover {
    transform: scale(1.04);
}

.gallery-item figcaption {
    padding: 10px 14px;
    font-size: 0.9rem;
    color: var(--color-dark);
    border-top: 1px solid var(--color-light-bg);
}

/* ── 11. LISTS ───────────────────────────────────────────── */
/* Ordered list — ported from WS03 with :nth-child striping  */

ol {
    background-color: var(--color-light-bg);
    border: 2px solid var(--color-primary);
    border-radius: var(--radius-md);
    padding: 12px 12px 12px 36px;
    list-style: decimal;
    color: var(--color-dark);
    line-height: 2;
}

ol li:nth-child(odd) {
    background-color: #d0e8f8;
    border-radius: var(--radius-sm);
    padding-left: 4px;
}

ol li:nth-child(even) {
    background-color: #b8d8f0;
    border-radius: var(--radius-sm);
    padding-left: 4px;
}

/* Unordered list — with :first-child and :last-child        */

ul {
    background-color: #fef9e7;
    border: 2px solid var(--color-gold);
    border-radius: var(--radius-md);
    padding: 12px 12px 12px 36px;
    list-style: square;
    color: #5d4037;
    line-height: 2;
}

ul li:first-child {
    color: var(--color-gold);
    text-decoration: underline;
}

ul li:last-child {
    font-style: italic;
    opacity: 0.7;
}

/* ── 12. FORM ────────────────────────────────────────────── */
/* Responsive form: full width on mobile, max-width on       */
/* tablet+. Reuses WS03/WS04 focus and hover states.         */

form {
    background: var(--color-white);
    border: 2px solid var(--color-primary);
    border-radius: var(--radius-lg);
    padding: 24px 20px;
    box-shadow: var(--shadow-sm);
    width: 100%;             /* full width on mobile */
}

form label {
    display: block;
    font-weight: bold;
    font-size: 0.95rem;
    color: var(--color-dark);
    margin-bottom: 4px;
}

form input[type="text"],
form input[type="email"],
form textarea {
    width: 100%;
    padding: 8px 10px;
    margin-bottom: 16px;
    border: 1px solid var(--color-primary);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-family: Georgia, serif;
    box-sizing: border-box;
    background: #f0f4f8;
    transition: border-color 0.2s ease, background 0.2s ease;
}

form textarea {
    min-height: 100px;
    resize: vertical;
}

form input[type="text"]:focus,
form input[type="email"]:focus,
form textarea:focus {
    outline: none;
    border-color: var(--color-dark);
    background: var(--color-white);
    box-shadow: 0 0 6px rgba(70, 130, 180, 0.5);
}

form input[type="submit"] {
    background: var(--color-primary);
    color: var(--color-white);
    padding: 10px 28px;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

form input[type="submit"]:hover {
    background: var(--color-dark);
}

/* ── 13. FOOTER ──────────────────────────────────────────── */

footer {
    background-color: var(--color-dark);
    color: #c8d8e8;
    text-align: center;
    padding: 16px;
    border-radius: var(--radius-md) var(--radius-md) 0 0;
    margin-top: 0;
}

footer p {
    margin: 0;
    font-size: 0.9rem;
    background: none;
    border: none;
    padding: 0;
    color: #c8d8e8;
}

footer p::first-letter {
    /* Reset drop-cap in footer */
    font-size: inherit;
    font-weight: inherit;
    color: inherit;
    float: none;
    margin-right: 0;
}

/* ── 14. ANIMATIONS & TRANSITIONS ───────────────────────── */
/* Ported from WS03/WS04                                     */

@keyframes slideInDown {
    from {
        transform: translateY(-40px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

/* ─────────────────────────────────────────────────────────
   RESPONSIVE BREAKPOINTS (mobile-first min-width queries)
   ───────────────────────────────────────────────────────── */

/* ── 15. MEDIA QUERY: TABLET (min-width: 600px) ─────────── */
/* Layout stays single-column but sidebar becomes visible.   */
/* Nav hamburger still shown (nav menu is compact).          */

@media (min-width: 600px) {
    .page-wrapper {
        padding-left: 24px;
        padding-right: 24px;
    }

    .site-header {
        padding: 24px 24px 0;
    }

    .site-header__content {
        padding: 22px 28px 24px;
    }

    nav {
        padding: 0 24px;
        margin-bottom: 28px;
    }

    /* Sidebar becomes visible on tablet (stacked above main) */
    aside {
        display: block;
    }

    /* Form gets max-width on tablet */
    form {
        max-width: 500px;
    }

    /* Gallery: 2 columns on tablet via auto-fit minmax */
    .gallery-grid {
        gap: 20px;
    }
}

/* ── 16. MEDIA QUERY: DESKTOP (min-width: 900px) ────────── */
/* CSS Grid two-column layout (sidebar + main).              */
/* Hamburger menu hidden; nav links always visible in row.   */

@media (min-width: 900px) {
    .page-wrapper {
        max-width: 1060px;
    }

    .site-header {
        padding: 32px 32px 0;
        max-width: 1060px;
        margin-left: auto;
        margin-right: auto;
    }

    .site-header__content {
        min-height: 28vh;
    }

    nav {
        max-width: 1060px;
        margin-left: auto;
        margin-right: auto;
        padding: 0 32px;
    }

    /* Hide hamburger; show nav links as flex row */
    .nav-toggle-label {
        display: none;
    }

    .nav-links {
        display: flex !important;           /* always visible on desktop */
        flex-direction: row;
        gap: 1.5rem;
        align-items: center;
        padding: 10px 0;
    }

    .nav-links a {
        padding: 4px 8px;
    }

    /* Switch to CSS Grid two-column layout */
    .layout-grid {
        display: grid;
        grid-template-columns: 260px 1fr;   /* fixed sidebar + flexible main */
        gap: 28px;
        align-items: start;
        max-width: 1060px;
        margin-left: auto;
        margin-right: auto;
        padding-left: 32px;
        padding-right: 32px;
    }

    /* Sticky sidebar on desktop */
    aside {
        position: sticky;
        top: 16px;
        margin-bottom: 0;
    }

    /* Cap image width on desktop for non-gallery images */
    main img:not(.gallery-item img) {
        max-width: 300px;
        width: 100%;
    }

    footer {
        max-width: 1060px;
        margin-left: auto;
        margin-right: auto;
    }
}

/* ── 17. MEDIA QUERY: WIDE (min-width: 1200px) ──────────── */
/* Slightly wider max-width, larger gap, bigger header.      */

@media (min-width: 1200px) {
    .page-wrapper,
    .site-header,
    nav,
    .layout-grid,
    footer {
        max-width: 1100px;
    }

    .layout-grid {
        gap: 36px;
    }

    .site-header__content {
        padding: 28px 36px 30px;
    }
}