* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    --bg: #f6f8fb;
    --surface: #ffffff;
    --text: #18202a;
    --muted: #667085;
    --border: #e4e9f0;
    --dark: #111827;
    --dark-soft: #1f2937;
    --green: #16803c;
    --green-bg: #eaf7ef;
    --yellow: #9a6700;
    --yellow-bg: #fff7df;
    --red: #c62828;
    --red-bg: #fdecec;
    --shadow: 0 10px 30px rgba(16, 24, 39, 0.07);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: Arial, Helvetica, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
}

a {
    color: inherit;
}

.container {
    width: min(1120px, calc(100% - 40px));
    margin: 0 auto;
}

/* =========================
   HEADER
========================= */

.site-header {
    background: var(--dark);
    color: #ffffff;
}

.header-content {
    min-height: 76px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
}

.brand {
    display: inline-flex;
    align-items: baseline;
    gap: 7px;
    text-decoration: none;
    white-space: nowrap;
}

.brand-main {
    font-size: 24px;
    font-weight: 800;
    letter-spacing: -0.8px;
}

.brand-tools {
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 1.5px;
    opacity: 0.72;
}

.header-tagline {
    font-size: 14px;
    color: #cbd5e1;
}

/* =========================
   HERO
========================= */

.hero {
    background: var(--surface);
    padding: 72px 0 76px;
    border-bottom: 1px solid var(--border);
}

.hero-content {
    text-align: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    padding: 7px 13px;
    margin-bottom: 22px;
    border: 1px solid var(--border);
    border-radius: 999px;
    background: #f8fafc;
    color: #526071;
    font-size: 13px;
    font-weight: 600;
}

.hero h1 {
    max-width: 760px;
    margin: 0 auto 14px;
    font-size: clamp(38px, 6vw, 62px);
    line-height: 1.08;
    letter-spacing: -2px;
    font-weight: 800;
}

.hero-subtitle {
    max-width: 620px;
    margin: 0 auto 34px;
    color: var(--muted);
    font-size: 18px;
}

/* =========================
   CHECKER
========================= */

.checker-card {
    max-width: 850px;
    margin: 0 auto;
    padding: 28px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    box-shadow: var(--shadow);
    text-align: left;
}

.checker-card label {
    display: block;
    margin-bottom: 9px;
    font-size: 14px;
    font-weight: 700;
}

.checker-input-row {
    display: flex;
    gap: 10px;
}

.checker-input-row input {
    flex: 1;
    min-width: 0;
    height: 54px;
    padding: 0 17px;
    border: 1px solid #cfd7e2;
    border-radius: 10px;
    outline: none;
    background: #ffffff;
    color: var(--text);
    font-size: 16px;
}

.checker-input-row input:focus {
    border-color: #7c8796;
    box-shadow: 0 0 0 3px rgba(17, 24, 39, 0.06);
}

.checker-input-row button {
    height: 54px;
    padding: 0 24px;
    border: 0;
    border-radius: 10px;
    background: var(--dark);
    color: #ffffff;
    font-size: 13px;
    font-weight: 800;
    letter-spacing: 0.4px;
    cursor: pointer;
    white-space: nowrap;
    transition: transform 0.2s ease, opacity 0.2s ease;
}

.checker-input-row button:hover {
    transform: translateY(-1px);
}

.checker-input-row button:disabled {
    cursor: wait;
    opacity: 0.65;
    transform: none;
}

.input-hint {
    margin-top: 9px;
    color: var(--muted);
    font-size: 12px;
}

/* =========================
   RESULT
========================= */

.result-section {
    padding: 64px 0;
}

.result-card {
    max-width: 900px;
    margin: 0 auto;
    padding: 34px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    box-shadow: var(--shadow);
}

.result-status {
    display: inline-flex;
    align-items: center;
    gap: 9px;
    margin-bottom: 15px;
    font-size: 13px;
    font-weight: 800;
    letter-spacing: 0.5px;
}

.status-indicator {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #98a2b3;
}

.result-card h2 {
    margin-bottom: 7px;
    font-size: 28px;
    line-height: 1.2;
    overflow-wrap: anywhere;
}

.result-message {
    color: var(--muted);
    margin-bottom: 28px;
}

.result-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
}

.result-item {
    padding: 18px;
    background: #f8fafc;
    border: 1px solid var(--border);
    border-radius: 12px;
}

.result-label {
    display: block;
    margin-bottom: 5px;
    color: var(--muted);
    font-size: 11px;
    font-weight: 800;
    letter-spacing: 0.7px;
}

.result-item strong {
    font-size: 18px;
}

.result-details {
    margin-top: 12px;
    padding: 17px 18px;
    border-top: 1px solid var(--border);
    color: var(--muted);
    font-size: 13px;
}

.result-details span {
    display: block;
    margin-bottom: 3px;
}

.result-details strong {
    display: block;
    color: var(--text);
    overflow-wrap: anywhere;
}

/* =========================
   EXPLANATION
========================= */

.explanation-section,
.status-guide-section,
.recent-section,
.more-tools-section {
    padding: 72px 0;
}

.explanation-section {
    background: #ffffff;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.section-heading {
    max-width: 720px;
    margin: 0 auto 38px;
    text-align: center;
}

.section-heading h2 {
    margin-bottom: 10px;
    font-size: clamp(28px, 4vw, 38px);
    line-height: 1.2;
    letter-spacing: -0.8px;
}

.section-heading p {
    color: var(--muted);
    font-size: 16px;
}

.explanation-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
}

.explanation-card {
    padding: 28px;
    background: #ffffff;
    border: 1px solid var(--border);
    border-radius: 14px;
}

.explanation-icon {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 18px;
    border-radius: 10px;
    background: #f1f4f8;
    font-weight: 800;
}

.explanation-card h3 {
    margin-bottom: 9px;
    font-size: 18px;
}

.explanation-card p {
    color: var(--muted);
    font-size: 14px;
}

/* =========================
   STATUS GUIDE
========================= */

.status-guide-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
}

.status-guide-card {
    padding: 24px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
}

.guide-status {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 48px;
    height: 30px;
    margin-bottom: 16px;
    padding: 0 10px;
    border-radius: 999px;
    font-size: 12px;
    font-weight: 800;
}

.guide-status.green {
    background: var(--green-bg);
    color: var(--green);
}

.guide-status.yellow {
    background: var(--yellow-bg);
    color: var(--yellow);
}

.guide-status.red {
    background: var(--red-bg);
    color: var(--red);
}

.status-guide-card h3 {
    margin-bottom: 7px;
    font-size: 17px;
}

.status-guide-card p {
    color: var(--muted);
    font-size: 14px;
}

/* =========================
   RECENT
========================= */

.recent-section {
    background: #ffffff;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.recent-placeholder {
    max-width: 720px;
    min-height: 120px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    border: 1px dashed #ccd5e1;
    border-radius: 14px;
    color: var(--muted);
}

.recent-placeholder span {
    font-size: 20px;
}

/* =========================
   MORE TOOLS
========================= */

.tools-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
}

.tool-card {
    display: flex;
    flex-direction: column;
    gap: 7px;
    padding: 24px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
    text-decoration: none;
    transition: border-color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

.tool-card:hover {
    border-color: #d4dce7;
    box-shadow: 0 8px 22px rgba(16, 24, 39, 0.06);
    transform: translateY(-2px);
}

.tool-card > span {
    font-size: 25px;
    margin-bottom: 3px;
}

.tool-card strong {
    font-size: 17px;
}

.tool-card small {
    color: var(--muted);
    font-size: 13px;
}

/* =========================
   FOOTER
========================= */

.site-footer {
    background: var(--dark);
    color: #ffffff;
    padding-top: 54px;
}

.footer-content {
    display: grid;
    grid-template-columns: 1.7fr repeat(3, 1fr);
    gap: 42px;
    padding-bottom: 42px;
}

.footer-brand p {
    max-width: 270px;
    margin-top: 13px;
    color: #aeb8c6;
    font-size: 14px;
}

.footer-column {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 9px;
}

.footer-column h3 {
    margin-bottom: 6px;
    font-size: 13px;
    color: #ffffff;
}

.footer-column a {
    color: #aeb8c6;
    font-size: 13px;
    text-decoration: none;
}

.footer-column a:hover {
    color: #ffffff;
}

.footer-bottom {
    padding: 20px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
    color: #8995a5;
    font-size: 12px;
}

/* =========================
   RESPONSIVE
========================= */

@media (max-width: 850px) {

    .header-content {
        min-height: 70px;
    }

    .hero {
        padding: 58px 0 62px;
    }

    .result-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .explanation-grid {
        grid-template-columns: 1fr;
    }

    .status-guide-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 600px) {

    .container {
        width: min(100% - 28px, 1120px);
    }

    .header-content {
        flex-direction: column;
        justify-content: center;
        gap: 3px;
        padding: 15px 0;
    }

    .header-tagline {
        font-size: 12px;
    }

    .hero {
        padding: 48px 0 52px;
    }

    .hero-badge {
        font-size: 12px;
    }

    .hero h1 {
        font-size: 40px;
        letter-spacing: -1.5px;
    }

    .hero-subtitle {
        font-size: 16px;
    }

    .checker-card {
        padding: 20px;
    }

    .checker-input-row {
        flex-direction: column;
    }

    .checker-input-row input,
    .checker-input-row button {
        width: 100%;
    }

    .result-section,
    .explanation-section,
    .status-guide-section,
    .recent-section,
    .more-tools-section {
        padding: 54px 0;
    }

    .result-card {
        padding: 24px 20px;
    }

    .result-grid {
        grid-template-columns: 1fr 1fr;
    }

    .result-item {
        padding: 15px;
    }

    .result-card h2 {
        font-size: 24px;
    }

    .status-guide-grid {
        grid-template-columns: 1fr;
    }

    .tools-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr 1fr;
        gap: 30px 20px;
    }

    .footer-brand {
        grid-column: 1 / -1;
    }
}

@media (max-width: 390px) {

    .hero h1 {
        font-size: 36px;
    }

    .result-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr;
    }

    .footer-brand {
        grid-column: auto;
    }
}