* {
    box-sizing: border-box;
}

html {
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
    background: #f4f6f8;
    margin: 0;
    padding: 30px 15px;
    color: #1a1a1a;
    width: 100%;
    overflow-x: hidden;
}

.container {
    max-width: 720px;
    width: 100%;
    margin: 0 auto;
    background: #ffffff;
    padding: 30px 35px 40px;
    border-radius: 6px;
    box-shadow: 0 1px 4px rgba(0,0,0,0.08);
}

h1 {
    font-size: 22px;
    margin: 0 0 12px;
    color: #0f2d52;
    line-height: 1.3;
}

.intro {
    font-size: 13.5px;
    line-height: 1.5;
    color: #4a4a4a;
    margin-bottom: 28px;
}

/* ===== Tablet (π.χ. iPad, μέχρι 900px) ===== */
@media (max-width: 900px) {
    .container {
        padding: 26px 26px 32px;
    }
}

/* ===== Mobile (μέχρι 600px) ===== */
@media (max-width: 600px) {
    body {
        padding: 16px 8px;
    }

    .container {
        padding: 20px 16px 28px;
        border-radius: 4px;
        box-shadow: none;
    }

    h1 {
        font-size: 19px;
    }

    .intro {
        font-size: 13px;
        margin-bottom: 22px;
    }

    label {
        font-size: 13px;
    }

    /* Μεγαλύτερα πλαίσια εισαγωγής για εύκολο touch */
    input[type="text"],
    input[type="email"],
    input[type="tel"],
    select {
        font-size: 16px; /* αποτρέπει αυτόματο zoom σε iOS Safari */
        padding: 11px 10px;
    }

    .submit-btn {
        width: 100%;
        padding: 14px 0;
        font-size: 16px;
    }

    .file-upload {
        flex-direction: column;
        align-items: flex-start;
        gap: 8px;
    }

    .file-upload-btn {
        width: 100%;
        justify-content: center;
    }

    .file-group input[type="file"] {
        width: 100%;
    }
}

/* ===== Πολύ μικρές οθόνες (μέχρι 360px) ===== */
@media (max-width: 360px) {
    h1 {
        font-size: 17px;
    }
}

.alert {
    padding: 12px 16px;
    border-radius: 4px;
    margin-bottom: 22px;
    font-size: 14px;
}

.alert-success {
    background: #e6f4ea;
    border: 1px solid #34a853;
    color: #1e7e34;
}

.alert-error {
    background: #fdecea;
    border: 1px solid #ea4335;
    color: #b3261e;
}

.form-group {
    margin-bottom: 18px;
}

label {
    display: block;
    font-size: 13.5px;
    font-weight: 600;
    margin-bottom: 6px;
    color: #1a1a1a;
}

.req {
    color: #d93025;
}

input[type="text"],
input[type="email"],
input[type="tel"],
select {
    width: 100%;
    padding: 11px 14px;
    font-size: 14px;
    border: 1.5px solid #d5dae0;
    border-radius: 8px;
    background: #fbfcfd;
    min-height: 44px;
    max-width: 100%;
    color: #1a1a1a;
    transition: border-color 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
    appearance: none;
}

select {
    background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%235a6573' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 18px;
    padding-right: 38px;
    cursor: pointer;
}

input::placeholder {
    color: #9aa3ad;
}

input:hover,
select:hover {
    border-color: #b7c0cb;
}

input:focus,
select:focus {
    outline: none;
    border-color: #1a4f8b;
    background: #fff;
    box-shadow: 0 0 0 3px rgba(26,79,139,0.12);
}

input.invalid,
select.invalid {
    border-color: #d93025;
    box-shadow: 0 0 0 3px rgba(217,48,37,0.10);
}

.error-msg {
    color: #d93025;
    font-size: 12.5px;
    margin-top: 4px;
    display: none;
}

.file-group {
    margin-bottom: 20px;
}

.file-upload {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.file-input-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    opacity: 0;
    overflow: hidden;
    z-index: -1;
}

.file-upload-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: #eef3f9;
    color: #1a4f8b;
    border: 1.5px solid #c8d6e8;
    padding: 10px 18px;
    border-radius: 8px;
    font-size: 13.5px;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.18s ease, border-color 0.18s ease, transform 0.12s ease;
    white-space: nowrap;
}

.file-upload-btn svg {
    flex-shrink: 0;
}

.file-upload-btn:hover {
    background: #dfe9f5;
    border-color: #1a4f8b;
}

.file-upload-btn:active {
    transform: scale(0.97);
}

.file-input-hidden:focus-visible + .file-upload-btn {
    outline: 2px solid #1a4f8b;
    outline-offset: 2px;
}

.file-input-hidden.invalid + .file-upload-btn {
    border-color: #d93025;
    background: #fdecea;
    color: #b3261e;
}
    font-size: 13px;
    color: #6b7480;
    font-style: italic;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 100%;
}

.file-name.has-file {
    color: #1e7e34;
    font-style: normal;
    font-weight: 500;
}

.submit-btn {
    margin-top: 14px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    background: linear-gradient(135deg, #1a4f8b 0%, #123a68 100%);
    color: #fff;
    border: none;
    padding: 13px 32px;
    font-size: 15.5px;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    box-shadow: 0 3px 10px rgba(26,79,139,0.28);
    transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}

.submit-btn svg {
    transition: transform 0.15s ease;
}

.submit-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 16px rgba(26,79,139,0.35);
    background: linear-gradient(135deg, #1f5a9e 0%, #14437a 100%);
}

.submit-btn:hover svg {
    transform: translateX(2px) translateY(-2px);
}

.submit-btn:active {
    transform: translateY(0);
    box-shadow: 0 2px 6px rgba(26,79,139,0.3);
}

.submit-btn:disabled {
    background: #97a6b8;
    cursor: not-allowed;
    box-shadow: none;
    transform: none;
}